1dc1753bf

DEMO MANUAL DC1753B

Description

LTC3880EUJ Dual Phase Step-Down DC/DC Controller with

Digital Power Management

Demonstration circuit 1753B is a dual phase single-output, synchronous buck converter featuring the LTC®3880EUJ, a dual phase current mode controller with digital power system management. There are two versions of the board available: n DC1753B-A: senses inductor current across a sense

resistor and has a default switching Freq of 350kHz.n DC1753B-B: senses inductor current with the inductor

DCR and has a default switching Freq of 425kHz.

Either version can be populated with the LTC3880EUJ-1, which allows the user to provide bias power to the IC from an external power supply.

The output voltage of the board can be programmed from 0.5V to 3.3V, with output current up to 40A. The factory default setting for the output is 1.8V.

The DC1753B powers up to default settings and pro-duces power based on configuration resistors without the need for any serial bus communication. This allows easy

L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and LTpowerPlay is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners.

performance summary

evaluation of the DC/DC converter aspects of the LTC3880. To fully explore the extensive digital power management features of the part, download the LTpowerPlay™ GUI software onto your PC and use LTC’s I2C/SMBus/PMBus dongle DC1613A to connect to the board. LTpowerPlay allows the user to reconfigure the part on-the-fly and store the configuration in EEPROM, view telemetry of voltage, current, temperature and fault status.

GUI DOWNLOAD

The software can be downloaded from: http://www.linear.com/ltpowerplay

For more details and instructions of LTpowerPlay, please refer to the LTpowerPlay for LTC3880 Quick Start Guide.

Design files for this circuit board are available at http://www.linear.com/demo/DC1753B

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

VIN Input Supply Range 6.5 12 24 V

VOUT Output Voltage Range IOUT = 0A to 20A, VIN = 6.5V to 24V 0.5 1.8 3.3 V

VOUT_ACCURACY Output Voltage Accuracy IOUT = 0A to 20A, VIN = 6.5V to 24V VOUT for 0.5V to 3.3V

±0.5 %

IOUT Output Current Range 0 40 A

fSW, A Factory Default Switching, Freq: A (RSENSE) 350 kHz

fSW, B Factory Default Switching, Freq: B (DCR) 425 kHz

EFFICIENCY Peak Efficiency VOUT = 1.8V, See Figures 6 and 7 91.8 %

Specifications are at TA = 25°C

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DEMO MANUAL DC1753B

dc1753b F01

LTC3880 Demo Board

DC1753B

USB to I2C/PMBus Dongle

DC1613A

+12V Power Supply

LOAD

USB CABLE

12-PIN J10

CONNECTOR

VOUT

VIN

Quick start proceDure

Figure 1. Demo Setup with PC

Demonstration circuit 1753B makes it easy to evaluate the performance of the LTC3880. Refer to Figure 3 for proper measurement equipment setup and follow the procedure below.

NOTE: When measuring the input or output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the output voltage ripple by touching the probe tip directly across the C20 or C23. See Figure 5 for the proper scope probe technique.

1. Make sure jumpers are in the following positions:

JUMPER POSITION FUNCTION

JP1 OFF Write Protection of LTC3880

JP3 ON LED Indicator

JP4 OFF EXTVCC_DRV: External VCC for the LTC3880-1

JP5 C GPIO0B to GPIO1B: Tie GPIOs Together

2. With power off, connect the input power supply to VIN and GND. Connect active load to outputs.

3. Make sure RUN switch is OFF.

4. Turn on the power at the input. .

NOTE: Make sure that the input voltage does not ex-ceed 24V.

5. Turn on the RUN switch as desired.

6. Check for the correct output voltages. VOUT = 1.8V ± 0.5%.

NOTE: If there is no output, temporarily disconnect the load to make sure that the load is not set too high.

7. Once the proper output voltages are established, adjust the loads within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters.

8. Connect the dongle and control the output voltages from the GUI. See next section for details.

CONNECTING A PC TO DC1753B

You can use a PC to reconfigure the power management features of the LTC3880, such as: nominal VOUT, margin set points, OV/UV limits, temperature fault limits, sequenc-ing parameters, the fault log, fault responses, GPIOs and other functionality. The DC1613A dongle may be plugged in regardless of whether or not VIN is present.

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DEMO MANUAL DC1753B

Quick start proceDurePlug the dongle into the correct connector. The dongle can be hot plugged.

Figure 2. Dongle Connector Locations

Figure 3. Dual Phase Single-Output Test Setup

dc1753b F02

DC1613ACONNECTOR

dc1753b F03

+–

SHUNT

VOUTLOAD

RUNSWITCH1

POWERSUPPLY

–

+

+

–

+

–

+ –

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DEMO MANUAL DC1753B

Combining DC1753B with Other Digital Power Demo Boards

The DC1753B may be plugged together in a multiboard array with other digital power boards using J7 and J8.

Measuring Efficiency

To accurately measure efficiency of any configuration, do the following:n Remove R65 (bleeder resistor on bottom side of board).n Set JP3 to OFF to disable the regulator that provides

power to LEDs.n Measure VIN across the input ceramic capacitor (C18,

C19). Measure VOUT across the output ceramic capaci-tor (C24, C25).

Evaluating the LTC3880-1

For applications that require the highest possible ef-ficiency, the LTC3880-1 allows the user to supply the bias current and gate driver current from an external power supply. Connect the power supply, 4.8V to 5.2V, to the INTVCC/EXTVCC pin. Obtain a DC1753B with an LTC3880-1 installed from your Linear Technology Field Applications Engineer.

To use the on-board LDO to drive INTVCC, make the following modifications to the demo board:n Set JP4 to ON so that U7 provides the drive to

INTVCC. U7 takes the place of the external power supply.n Install R60.

To accurately measure efficiency of a demo board contain-ing an LTC3880-1: n Drive INTVCC from an external source through the

pin named: INTVCC/EXTVCC. Install R60, R65 if installed

n Set JP4 to OFF to disable U7.n Set JP3 to OFF to disable the regulator that provides

power to LEDs. n Measure VIN across the input ceramic capacitor (C18,

C19). Measure VOUT across the output ceramic capaci-tor (C24, C25).

Measuring Output Ripple Voltage

An accurate ripple measurement may be performed by using the configuration in Figure 5 across C20 or C23.

Quick start proceDure

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DEMO MANUAL DC1753B

Figure 5. Measuring Output Voltage Ripple

Quick start proceDure

+ –

VOUT GND

COUT

dc1753b F05

Figure 4. Jumper Locations: JP3, JP4, R60, INTVCC/EXTVCC Turret

JP3JP4

INTVCCEXTVCC

R60

dc1753b F04

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DEMO MANUAL DC1753B

Figure 7. Typical Efficiency Curves, DCR Current Sensing, 12VIN, fSW = 425kHz

Figure 6. Typical Efficiency Curves, Sense Resistor Current Sensing, 12VIN, fSW = 350kHz

Quick start proceDure

OUTPUT CURRENT (A)

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82

84

88

105 15 4030 352520

86

90

92

81

83

85

89

87

91

dc1753b F06

12VIN, 1.8VOUT, 350kHz, RSENSE

12VIN, 1.5VOUT, 350kHz, RSENSE

12VIN, 1.2VOUT, 350kHz, RSENSE

12VIN, 1.0VOUT, 350kHz, RSENSE

OUTPUT CURRENT (A)

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82

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105 15 4030 352520

86

90

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81

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89

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dc1753b F07

12VIN, 1.8VOUT, 425kHz, DCR SENSE

12VIN, 1.5VOUT, 425kHz, DCR SENSE

12VIN, 1.2VOUT, 425kHz, DCR SENSE

12VIN, 1.0VOUT, 425kHz, DCR SENSE

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DEMO MANUAL DC1753B

Figure 8. LTpowerPlay Software GUI

LTpowerPlay Software GUI

LTpowerPlay is a powerful Windows based development environment that supports Linear Technology digital power ICs with EEPROM, including the LTC3880, LTC2974 and LTC2978, the quad and octal PMBus power supply man-agers. The software supports a variety of different tasks. You can use LTpowerPlay to evaluate Linear Technology ICs by connecting to a demo board system. LTpowerPlay can also be used in an offline mode (with no hardware present) in order to build a multichip configuration file that can be saved and reloaded at a later time. LTpowerPlay provides unprecedented diagnostic and debug features. It becomes a valuable diagnostic tool during board bring-up

to program or tweak the power management scheme in a system, or to diagnose power issues when bringing up rails. LTpowerPlay utilizes the DC1613A USB-to-SMBus controller to communicate with one of many potential targets, including the LTC2974’s DC1978A demo system, or a customer board. The software also provides an au-tomatic update feature to keep the software current with the latest set of device drivers and documentation. The LTpowerPlay software can be downloaded from:

http://linear.com/ltpowerplay

To access technical support documents for LTC Digital Power Products visit Help. View online help on the LTpowerPlay menu.

Quick start proceDure

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DEMO MANUAL DC1753B

Gui Quick start proceDureLTpowerPlay Software GUI

The following procedure describes how to use LTpowerPlay to monitor and change the settings of LTC3880.

1. Download and install the LTPowerPlay GUI:

http://linear.com/ltpowerplay

2. Launch the LTpowerPlay GUI.

a. The GUI should automatically identify the LTC3880. The system tree on the left hand side should look like this:

b. A green message box shows for a few seconds in the lower left hand corner, confirming that the LTC3880 is communicating:

c. In the tool bar, click the “R” (RAM to PC) icon to read the RAM from the LTC3880. This reads the configuration from the RAM of LTC3880 and loads it into the GUI.

d. To change the output voltage to a different value, like 1.5V: In the Config tab, type 1.5 in the VOUT_COMMAND box, like this:

Then, click the “W” (PC to RAM) icon to write these register values to the LTC3880. After finishing this step, you will see the output voltage will change to 1.5V.

If the write is successful, this message appears:

e. To save the changes into the NVM: In the tool bar, click the “RAM to NVM” button:

f. Save the demo board configuration to a (*.proj) file by clicking the Save icon and save the file with a new file name.

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DEMO MANUAL DC1753B

parts ListITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER

Required Circuit Components1 3 C1, C2, C6 CAP., X7R, 0.1µF, 50V, 10%, 0603 AVX, 06035C104KAT2A2 1 C17 CAP., X7R, 0.22µF, 25V, 10%, 0603 TDK, C1608X7R1E224K3 2 C3, C9 CAP., X7R, 1µF, 16V, 10%, 0603 AVX, 0603YC105KAT2A4 1 C5 CAP., X5R, 4.7µF, 25V, 0805 TAIYO YUDEN, TMK212BJ475KG-T5 1 C8 CAP., X7R, 4700PF, 10%, 50V, 0603 AVX, 06035C472KAT2A6 4 C10, C29, C11, C30 CAP, POSCAP, 330µF, 6.3V, D3L SANYO, 6TPF330M9L7 1 C13 CAP, OS-CON 150µF, 35V SUNCON, 35HVP150M8 4 C20, C23-25 CAP., X5R, 100µF, 6.3V, 1210 AVX, 12106D107MAT2A9 2 C12, C14 CAP., X7R, 0.01µF, 10%, 50V, 0603 AVX, 06035C103KAT2A

10 2 C21, C22 CAP., X5R, 1000pF, 25, 10%, 0603 AVX, 06035C102JAT2A11 2 C15, C16 CAP., X7R, 100pF, 5%, 50V, 0603 AVX, 06035C101KAT2A12 4 C18, C19, C27, C28 CAP., X5R, 10µF, 35V, 1210 TAIYO YUDEN, GMK325BJ106KN13 1 C48 CAP., X5R, 10µF, 6.3V 0603 TDK, C1608X5R0J106M14 2 D1, D2 DIODE, SCHOTTKY, SOD-323 CENTRAL CMDSH-3TR15 2 Q1, Q3 OPTIMOS3 POWER-TRANSISTOR, PG-TDSON-8 INFINEON, BSC050N03LS16 2 Q2, Q4 OPTIMOS3 POWER-TRANSISTOR, PG-TDSON-8 INFINEON., BSC011N03LSI17 2 Q5, Q6 TRANS, GP, SS, PNP, 40V, SOT-23 ON SEMI MMBT3906LT1G18 1 Q11 MOSFET P-CH, 20V, 0.58A, SOT-23 VISHAY TP0101K-T1-E319 9 R5, R17, R39, R40-R42, R44, R45, R57 RES., CHIP, 10k, 5%, 0603 VISHAY, CRCW060310K0JNEA20 1 R66 RES., CHIP, 24.3k, 1%, 0603 VISHAY, CRCW060324K3FKEA21 10 R8, R25, R56, R59, R6, R29, R30, R34,

R67, R63RES., CHIP, 0 0603 YAGEO, RC0603FR-070RL

22 1 R3 RES., CHIP, 4.87k, 1%, 0603 AAC, CR16-4871FM23 1 R24 RES., CHIP, 15.8k, 1%, 0603 VISHAY, CRCW060315K8FKEA24 1 R52 RES., CHIP, 2, 1%, 0603 YAGEO, RC0603FR-072RL25 2 R10, R16 RES., 0.002, 2512, 1% PANASONIC, ERJ-M1WTF2M0U26 4 R11, R12, R13, R14 RES., CHIP, 100, 1%, 0603 VISHAY, CRCW0603100RFKEA27 2 L1, L2 INDUCTOR, 0.4µH VITEC., 59PR987528 1 U4 IC, LTC3880EUJ, QFN 6mm × 6mm LINEAR TECH., LTC3880EUJ#010J-1PBF

Gui Quick start proceDureLoading a LTC3880 Configuration (*.proj) File with the GUIn In the upper left hand corner of the GUI: File > Open > browse

to your *.proj file. This will load the file into the GUI.n Click the “Go On Line” button to link the GUI to the

existing LTC3880, as this:

n Click on the “W” (PC to RAM) button. This loads the configuration into LTC3880 RAM.

n Then, you can save the configuration to the EEPROM. Please see previous step f for details.

DC1753B-A

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DEMO MANUAL DC1753B

parts ListITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER

Additional Circuit Components1 1 C50 CAP., X7R, 0.1µF, 50V, 10%, 0603 AVX, 06035C104KAT2A2 1 C49 CAP., X5R, 4.7µF, 10V, 0603 AVX, 0603ZD475KAT2A3 0 C42-C45 CAP, POSCAP, 330µF, 6.3V, D3L4 0 C4, C38 CAP., 06035 0 C32, C34 CAP., 12106 1 C46 CAP., X7R, 0.01µF, 10%, 50V, 0603 AVX, 06035C103KAT2A7 1 C35 CAP., X5R, 10µF, 35V, 1206 TAIYO YUDEN, GMK316BJ106ML8 1 C36 CAP., TANT LOW ESR, 3.3µF, 25V, 10% AVX, TPSB335K025R20009 2 C37, C40 CAP., X7R, 1µF, 50V, 1206 AVX, 12065C105KAT2A

10 1 C41 CAP., X7R, 2.2µF, 16V, 0805 AVX, 0805YC223KAT2A11 1 D3 LED GREEN S-GW TYPE SMD PANASONIC LN1371SGTRP12 1 D5 LED RED S-TYPE GULL WING SMD PANASONIC LN1271RTR13 0 D6, D9 DIODE, SCHOTTKY, SOD-323 CENTRAL CMDSH-3TR14 1 Q15 MOSFET SPEED SRS 30V, 30A, LFPAK RENESAS RJK0305DPB-00#J015 0 Q7, Q8, Q9, Q10 OPTIMOS3 POWER-TRANSISTOR, PG-TDSON-816 1 Q14 MOSFET P-CH, 20V, 0.58A, SOT-23 VISHAY TP0101K-T1-E317 1 Q12 MOSFET N-CH, 60V, 115MA, SOT-23 FAIRCHILD 2N7002A18 4 R49, R62, R64, R66 RES CHIP, 10k, 5%, 0603 VISHAY, CRCW060310K0JNEA19 4 R48, R90, R83, R77 RES CHIP, 0, 0603 YAGEO, RC0603FR-070RL20 0 R18, R20, R22, R23, R32, R73, R70, R1,

R2, R7, R15, R94, R95, R81, R82, R96, R79, R80

RES., CHIP, 0603

21 2 R84, R85 RES., CHIP, 4.99k, 1%, 0603 YEGEO, RC0603FR-074K99L22 2 R50, R61 RES., CHIP, 1.5k, 1%, 0603 VISAY, CRCW06031K50FKEA23 1 R53 RES., CHIP, 200, 1%, 0603 YAGEO, RC0603FR-07200RL24 1 R55 RES., CHIP, 127, 1%, 0603 VISHAY, CRCW0603127RFKEA25 0 R65 RES., CHIP, 30, 1%, 1W 251226 1 R68 RES., CHIP, 0.01, 1%, 2010 VISHAY, WSL2010R0100FEA27 0 R60 RES., 080528 1 R38 RES., CHIP, 49.9, 1%, 060329 1 U5 IC, 24LC025-I/ST, SOIC MICROCHIP, 24LC025-I/ST30 1 U6 IC, LT1129CS8-3.3 S8 PACKAGE LINEAR TECH. LT1129CS8-3.331 1 U7 IC, LT1129CS8-5, S8 PACKAGE LINEAR TECH, LT1129CS8-5

Hardware1 4 JP1, JP3-JP5 0.100" SINGLE ROW HEADER, 3 PIN SAMTEC, TSW-103-07-L-S

2 4 JP1, JP3-JP5 SHUNT .100" BLK SAMTEC, SNT-100-B-G3 1 SW1 CONNECTOR, SUB MINIATURE SLIDE SWITCHES C&K.,JS202011CQN4 2 J1, J2 JACK, BANANA KEYSTONE 575-45 4 J3, J4(×2) STUD, TESTPIN PEM KFH-032-106 4 J3, J4(×2) NUT, BRASS 10-32 ANY #10-327 1 J14 CONN., HEADER, 2 × 7, 2mm, R/A (F) SULLINS, NPPN072FJFN-RC8 1 J15 CONN., HEADER, 2 × 7, 2mm, R/A (M) MOLEX, 87760-14169 0 J9 (OPT) HEADER 14POS 2mm VERT GOLD MOLEX 87831-1420

10 1 J10 CONN HEADER 12POS 2mm, STR DL PCB FCI 98414-G06-12ULF11 1 J11 CONN, BNC, 5 PINS CONNEX, 11240412 28 E1-E21, E23, E24, E25, E27, E31, E33 TESTPOINT, TURRET, .062" MILL-MAX, 2308-2-00-80-00-00-07-0

DC1753B-A

11dc1753bf

DEMO MANUAL DC1753B

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ERIN

G FO

R AS

SIST

ANCE

.

THIS

CIR

CUIT

IS P

ROPR

IETA

RY T

O LI

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TEC

HNOL

OGY

AND

SCHE

MAT

IC

SUPP

LIED

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USE

WIT

H LI

NEAR

TEC

HNOL

OGY

PART

S.SC

ALE

= NO

NE

www.

linea

r.com 1

Mond

ay, J

uly 21

, 201

41

3

DUAL

-PHA

SE S

INGL

E OU

TPUT

STE

P-DO

WN

DC/D

C

HZ YI S

.

N/A

LTC3

880E

UJDE

MO C

IRCU

IT 17

53B-

A/B

SIZE

DATE

:

.VER.ON CI

SHEE

TOF

TITL

E:

APPR

OVAL

S

PCB

DES.

APP

ENG.

TEC

HN

OLO

GY

Fax:

(408

)434

-050

7

Milp

itas,

CA 95

035

Phon

e: (4

08)4

32-1

900

1630

McC

arth

y Blvd

.

LTC

Conf

iden

tial-F

or C

usto

mer

Use

Onl

y

CUST

OMER

NOT

ICE

LINE

AR T

ECHN

OLOG

Y HA

S MA

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UIT

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CIFI

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ONS;

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, IT R

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HE C

USTO

MER'

S RE

SPON

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INEA

RTE

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G FO

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MAT

IC

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LIED

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USE

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H LI

NEAR

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HNOL

OGY

PART

S.SC

ALE

= NO

NE

www.

linea

r.com 1

Mond

ay, J

uly 21

, 201

41

3

DUAL

-PHA

SE S

INGL

E OU

TPUT

STE

P-DO

WN

DC/D

C

HZ YI S

.

N/A

LTC3

880E

UJDE

MO C

IRCU

IT 17

53B-

A/B

C12

10nF

C12

10nF

R14

R14

C28

10uF

C28

10uF

E2VI

NE2

VIN

D2D2

2 1

R22

OPT

R22

OPT

E8

GND_

SNS

E8

GND_

SNS

R32

OPT

R32

OPT

L2L2

E4

VDD3

3 E4

VDD3

3

R40

10K

R40

10K

R7R7

C3 1uF

C3 1uF

J4GN

DJ4

GND

R57

10K

R57

10K

R18

OPT

R18

OPT

R1R1

E11

SGND

E11

SGND

C25

100u

FC2

510

0uF

C27

10uF

C27

10uF

C32

C32

L1L1

R44

10K

R44

10K

Q6Q6

Q9OPT

Q9OPT

12

53

4C2

410

0uF

C24

100u

F

C23

100u

FC2

310

0uF

R42

10K

R42

10K

R34

R34

R11

R11

E10

INTV

CC/E

XTVC

C

E10

INTV

CC/E

XTVC

C

R41

10K

R41

10K

J1VI

NJ1

VIN

R29

R29

C16

100p

FC1

610

0pF

C22 *C22 *

R23 OP

TR2

3 OPT

C210

0nF

C210

0nF

R59

0R5

90

R25

0R25

0

Q8 OPT

Q8 OPT

12

53

4

+C1

315

0uF

+C1

315

0uF

+

C44

+

C44

C34

C34

+C4

2+

C42

R45

10K

R45

10K

R8 0R8 0

E9IT

HE9

ITH

R10

R10

J2GN

DJ2

GND

C4C4

C48

10uF

C48

10uF

R67

0R6

70

C15

100p

FC1

510

0pF

R3 4.87

KR3 4.87

K

C8 4.7n

FC8 4.

7nF

E5VDD2

5

E5VDD2

5

R12

R12

C9 1uF

C9 1uF

+C4

3+

C43

C18

10uF

C18

10uF

Q5Q5

C21

C21

E1GN

DE1

GND

C110

0nF

C110

0nF

+

C30

330u

F

+

C30

330u

F

R60

OPT

R60

OPT

Q3BS

C050

N03L

SQ3

BSC0

50N0

3LS

12

53

4

U4

LTC

3880

EU

JU

4LT

C38

80E

UJ VS

ENSE

0+1

VSEN

SE0-

2

ISNS

1+3

ISNS

1-4

ITH0

5

ISNS

0+6

ISNS

0-7

SYNC

8

SCL

9

SDA

10

ALER

T11

GPIO

012

GPIO

113

RUN0

14RU

N115

ASEL

16

FREQ

_CFG

17

VOUT

0_CF

G18

VOUT

1_CF

G19

VTRI

M0_

CFG

20

VTRI

M1_

CFG

21

VDD2522

WP

23

SC24

VDD3325

ITH1

26

VSEN

SE1

27

TSNS

128

SW1

29

TG1

30

BOOS

T131

BG1

32

INTVCC33

PGND 34

VIN35

BG0

36

BOOS

T037

TG0

38

SW0

39

TSNS

040

GND 41

C38

C38

Q10

OPT

Q10

OPT

12

53

4

R17

10K

R17

10K

R13

R13

R20

OPT

R20

OPT

R63

0R6

30

Q1 BSC050N03LS Q1 BSC050N03LS

12

53

4

R15

R15

+C2

933

0uF

+C2

933

0uF

+

C45

+

C45

E6

GND E6

GND

E7

VOUT

_SNS

E7

VOUT

_SNS

+

C11

330u

F

+

C11

330u

F

R2R2

R52

2R5

22

C14

10nF

C14

10nF

C19

10uF

C19

10uF

R73

OPT

R73

OPT

R48

0R4

80

R16

R16

D1D1

2 1

R39

10K

R39

10K

R56

0R5

60

E3GN

DE3

GND JP

1JP

1

1

2

3

Q4 B

SC01

1N03

LSI

Q4 B

SC01

1N03

LSI

12

53

4

J3VO

UTJ3

VOUT

R30

R30

R24

15.8

KR2

415

.8K

C6 100n

FC6 10

0nF

Q2 B

SC01

1N03

LSI

Q2 B

SC01

1N03

LSI

12

53

4

Q7 OPT

Q7 OPT

12

53

4

R6R6

+C1

033

0uF

+C1

033

0uF

C20

100u

FC2

010

0uF

C17

0.22

uFC1

70.

22uF

C5 4.7u

FC5 4.

7uF

R5 10K

R5 10K

schematic DiaGram

12dc1753bf

DEMO MANUAL DC1753B

Figu

re 1

0. D

emo

Circ

uit 1

753B

Dua

l-Pha

se, S

ingl

e-Ou

tput

, Ste

p-Do

wn

DC/D

C Co

nver

ter w

ith D

igita

l Pow

er M

anag

emen

t

5 5

4 4

3 3

2 2

1 1

DD

CC

BB

AA

CONV

ERTE

R W

ITH

DIGI

TAL

POW

ER M

ANAG

EMEN

T

CN

CG

PIO

0-G

PIO

1

TO D

C16

13A

ALL

PA

RTS

ON

TH

IS P

AG

E A

RE

FO

R D

EM

O B

OA

RD

ON

LY, N

OT

NE

ED

ED

IN C

US

TOM

ER

DE

SIG

N

ON

OFF

RU

N

1206

AU

XV

CC

EE

WP

EE

SD

A

EE

SC

L

VDD3

3

3V3

VIN

3V3

VIN

ALER

TBSD

ASC

L

RUN

RUN1

GPIO

1B

GPIO

0B

SYNC

SHAR

E_CL

K

SIZE

DATE

:

.VER.ON CI

SHEE

TOF

TITL

E:

APPR

OVAL

S

PCB

DES.

APP

ENG.

TEC

HN

OLO

GY

Fax:

(408

)434

-050

7

Milp

itas,

CA 95

035

Phon

e: (4

08)4

32-1

900

1630

McC

arth

y Blvd

.

LTC

Conf

iden

tial-F

or C

usto

mer

Use

Onl

y

CUST

OMER

NOT

ICE

LINE

AR T

ECHN

OLOG

Y HA

S MA

DE A

BES

T EF

FORT

TO

DESI

GN A

CIRC

UIT

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MEE

TS C

USTO

MER-

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LIED

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CIFI

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ONS;

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, IT R

EMAI

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HE C

USTO

MER'

S RE

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LITY

TO

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FY P

ROPE

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TION

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INTE

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TY. C

ONTA

CT L

INEA

RTE

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LOGY

APP

LICA

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S EN

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ERIN

G FO

R AS

SIST

ANCE

.

THIS

CIR

CUIT

IS P

ROPR

IETA

RY T

O LI

NEAR

TEC

HNOL

OGY

AND

SCHE

MAT

IC

SUPP

LIED

FOR

USE

WIT

H LI

NEAR

TEC

HNOL

OGY

PART

S.SC

ALE

= NO

NE

www.

linea

r.com 1

Mond

ay, J

uly 21

, 201

42

3

DUAL

-PHA

SE S

INGL

E OU

TPUT

STE

P-DO

WN

DC/D

C

HZ YI S

.

N/A

LTC3

880E

UJDE

MO C

IRCU

IT 17

53B-

A/B

SIZE

DATE

:

.VER.ON CI

SHEE

TOF

TITL

E:

APPR

OVAL

S

PCB

DES.

APP

ENG.

TEC

HN

OLO

GY

Fax:

(408

)434

-050

7

Milp

itas,

CA 95

035

Phon

e: (4

08)4

32-1

900

1630

McC

arth

y Blvd

.

LTC

Conf

iden

tial-F

or C

usto

mer

Use

Onl

y

CUST

OMER

NOT

ICE

LINE

AR T

ECHN

OLOG

Y HA

S MA

DE A

BES

T EF

FORT

TO

DESI

GN A

CIRC

UIT

THAT

MEE

TS C

USTO

MER-

SUPP

LIED

SPE

CIFI

CATI

ONS;

HOW

EVER

, IT R

EMAI

NS T

HE C

USTO

MER'

S RE

SPON

SIBI

LITY

TO

VERI

FY P

ROPE

R AN

D RE

LIAB

LE O

PERA

TION

IN T

HE A

CTUA

LAP

PLIC

ATIO

N. C

OMPO

NENT

SUB

STIT

UTIO

N AN

D PR

INTE

DCI

RCUI

T BO

ARD

LAYO

UT M

AY S

IGNI

FICA

NTLY

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ECT

CIRC

UIT

PERF

ORMA

NCE

OR R

ELIA

BILI

TY. C

ONTA

CT L

INEA

RTE

CHNO

LOGY

APP

LICA

TION

S EN

GINE

ERIN

G FO

R AS

SIST

ANCE

.

THIS

CIR

CUIT

IS P

ROPR

IETA

RY T

O LI

NEAR

TEC

HNOL

OGY

AND

SCHE

MAT

IC

SUPP

LIED

FOR

USE

WIT

H LI

NEAR

TEC

HNOL

OGY

PART

S.SC

ALE

= NO

NE

www.

linea

r.com 1

Mond

ay, J

uly 21

, 201

42

3

DUAL

-PHA

SE S

INGL

E OU

TPUT

STE

P-DO

WN

DC/D

C

HZ YI S

.

N/A

LTC3

880E

UJDE

MO C

IRCU

IT 17

53B-

A/B

SIZE

DATE

:

.VER.ON CI

SHEE

TOF

TITL

E:

APPR

OVAL

S

PCB

DES.

APP

ENG.

TEC

HN

OLO

GY

Fax:

(408

)434

-050

7

Milp

itas,

CA 95

035

Phon

e: (4

08)4

32-1

900

1630

McC

arth

y Blvd

.

LTC

Conf

iden

tial-F

or C

usto

mer

Use

Onl

y

CUST

OMER

NOT

ICE

LINE

AR T

ECHN

OLOG

Y HA

S MA

DE A

BES

T EF

FORT

TO

DESI

GN A

CIRC

UIT

THAT

MEE

TS C

USTO

MER-

SUPP

LIED

SPE

CIFI

CATI

ONS;

HOW

EVER

, IT R

EMAI

NS T

HE C

USTO

MER'

S RE

SPON

SIBI

LITY

TO

VERI

FY P

ROPE

R AN

D RE

LIAB

LE O

PERA

TION

IN T

HE A

CTUA

LAP

PLIC

ATIO

N. C

OMPO

NENT

SUB

STIT

UTIO

N AN

D PR

INTE

DCI

RCUI

T BO

ARD

LAYO

UT M

AY S

IGNI

FICA

NTLY

AFF

ECT

CIRC

UIT

PERF

ORMA

NCE

OR R

ELIA

BILI

TY. C

ONTA

CT L

INEA

RTE

CHNO

LOGY

APP

LICA

TION

S EN

GINE

ERIN

G FO

R AS

SIST

ANCE

.

THIS

CIR

CUIT

IS P

ROPR

IETA

RY T

O LI

NEAR

TEC

HNOL

OGY

AND

SCHE

MAT

IC

SUPP

LIED

FOR

USE

WIT

H LI

NEAR

TEC

HNOL

OGY

PART

S.SC

ALE

= NO

NE

www.

linea

r.com 1

Mond

ay, J

uly 21

, 201

42

3

DUAL

-PHA

SE S

INGL

E OU

TPUT

STE

P-DO

WN

DC/D

C

HZ YI S

.

N/A

LTC3

880E

UJDE

MO C

IRCU

IT 17

53B-

A/B

R82

OPT

R82

OPT

R49

10.0

KR4

910

.0K

C46

10nF

C46

10nF

E17

SY

NC E1

7

SY

NC

E21

GN

DE21

GN

D

R77

10R77

10

R83

0R8

30

J15

DEM

O HE

ADER

(M)

J15

DEM

O HE

ADER

(M)

FAUL

TB1

CTRL

2AL

ERTB

3SD

A4

SHAR

E_CL

K5

SCL

6RE

SETB

7AU

XP8

UNUS

ED9

UNUS

ED10

GND

11GN

D12

12V

1312

V14

R94

OP

TR9

4O

PT

E13

ALE

RTB E1

3

ALE

RTB

R84

4.99

KR8

44.

99K

E20 R

UN

E20 R

UN

D9

OP

TD

9O

PT

SW1

SW1

1

2

34

5

6

E15

SC

L E15

SC

L

U5 24LC

025-

I/ST

U5 24LC

025-

I/ST

A01

A12

A23

VSS

4SD

A5

SCL

6W

P7

VCC

8

R95

OP

TR9

5O

PT

E16

SH

AR

E_C

LK E16

SH

AR

E_C

LK

E33 R

UN

1E3

3 RU

N1

E19 G

PIO

0BE1

9 GP

IO0B

R85

4.99

KR8

54.

99K

E14

SD

A E14

SD

A

JP5

JP5

1

2

3

R79

0R7

90

C50

100n

F

C50

100n

F

D6

OP

TD

6O

PT

R90

0R90

0

R81

OPT

R81

OPT

E31 S

GN

DE3

1 SG

ND

R86

OPT

R86

OPT

E25 G

PIO

1BE2

5 GP

IO1B

R80

OP

TR8

0O

PT

R87

OP

TR8

7O

PT

J10

J10

AUXP

1SD

A2

GND

3SC

L4

LGKP

WR

5AL

ERTB

6GP

IO_1

7OU

TEN_

08

OUTE

N_1

9GN

D10

AUXS

CL11

AUXS

DA12

J14

DEM

O HE

ADER

(F)

J14

DEM

O HE

ADER

(F)

FAUL

TB1

CTRL

2AL

ERTB

3SD

A4

SHAR

E_CL

K5

SCL

6RE

SETB

7AU

XP8

UNUS

ED9

UNUS

ED10

GND

11GN

D12

12V

1312

V14

R96

OP

TR9

6O

PT

R70

OP

TR7

0O

PT

schematic DiaGram

13dc1753bf

DEMO MANUAL DC1753B

Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Figu

re 1

1. D

emo

Circ

uit 1

753B

Dua

l-Pha

se, S

ingl

e-Ou

tput

, Ste

p-Do

wn

DC/D

C Co

nver

ter w

ith D

igita

l Pow

er M

anag

emen

t

5 5

4 4

3 3

2 2

1 1

DD

CC

BB

AA

LED ON OF

F

GPIO

0B

ALER

TB

ALL

PART

S ON

THI

S PA

GE A

RE F

OR D

EMO

ONLY

, NOT

NEE

DED

IN C

USTO

MER

DES

IGN

EXTV

CC_D

RV

ON OFF

DYNA

MIC

LOA

D CI

RCUI

T

DO N

OT E

XCEE

D 5%

DUT

Y CY

CLE!

NOTE

:PU

LSE

OUT

10m

V / A

MP

VOUT

IOUT

TST

2512

OPT

0805

3528

1206

1206

1206

CONV

ERTE

R W

ITH

DIGI

TAL

POW

ER M

ANAG

EMEN

T

+3.3

V

VIN

+3.3

V+3

.3V

VOUT

VIN

VOUT 3V

3VD

D33

VIN

EXTV

CC_D

RV

GPIO

0B

ALER

TB

VIN

SIZE

DATE

:

.VER.ON CI

SHEE

TOF

TITL

E:

APPR

OVAL

S

PCB

DES.

APP

ENG.

TEC

HN

OLO

GY

Fax:

(408

)434

-050

7

Milp

itas,

CA 95

035

Phon

e: (4

08)4

32-1

900

1630

McC

arth

y Blvd

.

LTC

Conf

iden

tial-F

or C

usto

mer

Use

Onl

y

CUST

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14dc1753bf

DEMO MANUAL DC1753B

Linear Technology Corporation1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2015

LT 0715 • PRINTED IN USA

DEMONSTRATION BOARD IMPORTANT NOTICE

Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:

This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.

If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.

The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.).

No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.

LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.

Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and observe good laboratory practice standards. Common sense is encouraged.

This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC applica-tion engineer.

Mailing Address:

Linear Technology

1630 McCarthy Blvd.

Milpitas, CA 95035

Copyright © 2004, Linear Technology Corporation