Skip to main content
Design DocumentAnalog

Analog Devices DC3103A Demonstration Circuit User Guide

DC3103A demonstrates the LT3942 4-switch buck-boost regulator, providing 12V output at 1A from a 3V-36V input with 2MHz switching frequency and SSFM for low EMI performance.

View design document

Overview

The DC3103A demonstration circuit is a monolithic 4-switch buck-boost voltage regulator featuring the LT3942. It provides a 12V output with up to 1A current capability when the input voltage is between 7V and 36V, though it can operate down to 3V with reduced power. The design is optimized for a 2MHz switching frequency and includes spread spectrum frequency modulation (SSFM) to enhance EMI performance. The LT3942 integrates synchronous 40V switches for high efficiency and supports both constant-voltage and constant-current regulation. The document includes a complete bill of materials, schematic diagram, and performance summaries such as efficiency vs. load and thermal imaging.

Use Cases

  • Automotive power supplies
  • Industrial voltage regulation
  • Battery-powered equipment
  • Constant voltage power conversion
  • High-efficiency DC-DC regulation

Topics

LT3942
DC3103A
buck-boost regulator
Analog Devices
synchronous converter
spread spectrum frequency modulation
SSFM
EMI reduction
12V regulator
monolithic regulator
4-switch converter

Referenced Parts

EEHZC1H220P

Panasonic

CAP., 22uF, ALUM POLY HYB, 50V, 20%, 6.3x5.8mm, SMD

EEHZK1E680P

Panasonic

CAP., 68uF, ALUM POLY HYB, 25V, 20%, 6.3x5.8mm, SMD

ERJ-2RKF1432X

Panasonic

RES., 14.3k OHMS, 1%, 1/10W, 0402, AEC-Q200

ERJ2RKF3482X

Panasonic

RES., 34.8k OHMS, 1%, 1/10W, 0402, AEC-Q200

60800213421

Wurth Electronics

CONN., SHUNT, FEMALE, 2 POS, 2mm

74438336033

Wurth Electronics

IND., 3.3uH, WE-MAPI, 20%, 2.2A, 114mOHMS, 3020

LT3942EUFD#PBF

Analog Devices

IC, 36V, 2A SYNC. BUCK-BOOST CVRTR, QFN-28

62000621121

Wurth Elektronik

CONN., HDR, MALE, 2x3, 2mm, VERT, ST, THT

QFN-28

Analog Devices

19 1 U1 IC, 36V, 2A SYNC. BUCK-BOOST CVRTR, QFN-28, ANALOG DEVICES, LT3942EUFD#PBF

AEC-Q200

Panasonic

16 1 R10 RES., 34.8k OHMS, 1%, 1/10W, 0402, AEC-Q200 PANASONIC, ERJ2RKF3482X

AEC-Q200

Panasonic

12 1 R4 RES., 14.3k OHMS, 1%, 1/10W, 0402, AEC-Q200 PANASONIC, ERJ2RKF1432X

AEC-Q200

Panasonic

14 1 R7 RES., 402k OHMS, 1%, 1/10W, 0402, AEC-Q200 PANASONIC, ERJ2RKF4023X

AEC-Q200

Panasonic

18 1 R12 RES., 324k OHMS, 1%, 1/10W, 0402, AEC-Q200 PANASONIC, ERJ2RKF3243X

AEC-Q200

Panasonic

8 2 R18, R19 RES., 0 OHM, 1/10W, 0402, AEC-Q200 PANASONIC, ERJ2GE0R00X

AEC-Q200

TDK

6 1 C6 CAP., 470pF, C0G, 50V, 5%, 0402, AEC-Q200 TDK, CGA2B2C0G1H471J050BA

AEC-Q200

Vishay

17 1 R11 RES., 1M OHM, 5%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW04021M00JNED

AEC-Q200

Vishay

9 1 R22 RES., 0 OHM, 1/16W, 0402, AEC-Q200 VISHAY, CRCW04020000Z0ED

AEC-Q200

Vishay

10 1 R2 RES., 110k OHMS, 1%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW0402110KFKED

AEC-Q200

Vishay

11 1 R3 RES., 10k OHMS, 5%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW040210K0JNED

AEC-Q200

Vishay

10 1 R13 RES., 100k OHMS, 5%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW0402100KJNED

AEC-Q200

Vishay

15 1 R9 RES., 100k OHMS, 5%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW0402100KJNED

2mm

Wurth Elektronik

4 1 XJP1 CONN., SHUNT, FEMALE, 2 POS, 2mm WURTH ELEKTRONIK, 60800213421