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LT3922-1 36V 2A Boost LED Driver Demonstration Circuit DC2857A

36V 2A synchronous 2MHz boost LED driver featuring the LT3922-1 with 25,000:1 PWM dimming, spread spectrum for low EMI, and support for LED strings up to 34V at 330mA.

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Overview

Demonstration circuit DC2857A is a synchronous 2MHz boost LED driver based on the LT3922-1 IC. It is designed to drive a single string of LEDs at 330mA up to 34V from an input range of 7V to 28V, though it can operate down to 4V with reduced current. The circuit features low EMI characteristics, including an optimized layout and spread spectrum frequency modulation (SSFM), allowing it to pass CISPR 25 class 5 standards. The LT3922-1 provides a 25,000:1 PWM dimming ratio at 100Hz and supports both internal and external PWM signal generation. Protection features include overvoltage lockout (OVLO) set at 28V, open LED overvoltage protection, and short-circuit protection with fault reporting.

Use Cases

  • Automotive LED Lighting
  • High-Contrast Display Backlighting
  • Industrial Lighting Systems
  • Battery-Powered LED Strings
  • Low-EMI Lighting Applications

Topics

LT3922-1
LT3922EUFD-1
DC2857A
Boost LED Driver
Synchronous Boost
PWM Dimming
Spread Spectrum
SSFM
CISPR 25
Analog Devices
330mA LED Driver

Referenced Parts

04026C104KAT2A

AVX

CAP., X7R, 100nF, 6.3V, 10%, 0402 AVX, 04026C104KAT2A

06036C225KAT2A

AVX

CAP., X7R, 2.2μF, 6.3V 10%, 0603 AVX, 06036C225KAT2A

3314J-1-104E

Bourns

TRIMMER., 100kΩ, 0.25W, SMD BOURNS, 3314J-1-104E

PMEG4010CEJ

NXP

DIODE, SCHOTTKY, 40V, 1A, SOD323F NXP, PMEG4010CEJ, 115

RL1220S-R30-F

Susumu

RES, CHIP, 0.3, 1/3W, 1%, 0805 SUSUMU, RL1220S-R30-F

UMK105ABJ474KV-F

Taiyo Yuden

CAP., X5R, 0.47μF, 50V, 10%, 0402 TAIYO YUDEN, UMK105ABJ474KV-F

CRCW040231K6FKED

Vishay

RES, CHIP, 31.6k, 1/16W, 1%, 0402 VISHAY, CRCW040231K6FKED

CRCW040245K3FKED

Vishay

RES, CHIP, 45.3k, 1/16W, 1%, 0402 VISHAY, CRCW040245K3FKED

CRCW060333K2FKEA

Vishay

RES, CHIP, 33.2k, 1/10W, 1%, 0603 VISHAY, CRCW060333K2FKEA

LT3922-1

Analog Devices

36V 2A synchronous 2MHz boost LED driver featuring the LT3922-1.

LT3922EUFD-1

Analog Devices

The LT3922EUFD-1 is assembled in a 28-lead plastic 4mm x 5mm QFN package

LT3922IUFD-1#PBF

Analog Devices

I.C., LED DRIVER, 28QFN 4X5 ANALOG DEVICES, LT3922IUFD-1#PBF

60800213421

Wurth Electronics

SHUNT, 0.079" CENTER WURTH ELEKTRONIK, 60800213421

742792040

Wurth Electronics

CHIP, BEAD, 600Ω, 0805 WURTH ELEKTRONIK, 742792040

742792097

Wurth Electronics

CHIP, BEAD, 1.5kΩ, 0805 WURTH ELEKTRONIK, 742792097

74437324047

Wurth Electronics

INDUCTOR, 4.7μH, 4.45mm x 4.06mm WURTH ELEKTRONIK, 74437324047

50CE33BS

Sun Electronic Industries Corporation

CAP., ALUM., 33μF, 50V, 20%, 6.3x7.7mm SUN ELECTRONIC INDUSTRIES CORPORATION, 50CE33BS

62000311121

Wurth Elektronik

HEADER 3 PIN 0.079 SINGLE ROW WURTH ELEKTRONIK, 62000311121

62000621121

Wurth Elektronik

HEADER 3 PIN 0.079 DOUBLE ROW WURTH ELEKTRONIK, 62000621121

4X5

Analog Devices

36 1 U1 I.C., LED DRIVER, 28QFN 4X5 ANALOG DEVICES, LT3922IUFD-1#PBF

SOD323F

NXP

14 1 D1 DIODE, SCHOTTKY, 40V, 1A, SOD323F NXP, PMEG4010CEJ, 115

SOT23

Vishay

22 1 M1 P-MOSFET, Si2319CDS, SOT23 VISHAY, SI2319CDS-T1-GE3

4.06mm

Wurth Elektronik

21 1 L1 INDUCTOR, 4.7μH, 4.45mm x 4.06mm WURTH ELEKTRONIK, 74437324047