Datasheet LTC3425 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 5A, 8MHz, 4-Phase Synchronous Step-Up DC/DC Converter |
| Pages / Page | 24 / 1 — FEATURES. DESCRIPTIO. High Efficiency: Up to 95%. Up to 3A Continuous … |
| File Format / Size | PDF / 284 Kb |
| Document Language | English |
FEATURES. DESCRIPTIO. High Efficiency: Up to 95%. Up to 3A Continuous Output Current. 4-Phase Operation for Low Output Ripple
Model Line for this Datasheet
Text Version of Document
LTC3425 5A, 8MHz, 4-Phase Synchronous Step-Up DC/DC Converter
U FEATURES DESCRIPTIO
■
High Efficiency: Up to 95%
The LTC®3425 is a synchronous, 4-phase boost converter ■
Up to 3A Continuous Output Current
with output disconnect capable of operation below 1V ■
4-Phase Operation for Low Output Ripple
input. It includes four N-channel MOSFET switches and
and Tiny Solution Size
four P-channel synchronous rectifiers for an effective ■
Output Disconnect and Inrush Current Limiting
RDS(ON) of 0.045Ω and 0.05Ω, respectively. 4-phase ■
Very Low Quiescent Current: 12
µ
A
operation greatly reduces peak inductor currents, and ■ 0.5V to 4.5V Input Range capacitor ripple current, and increases effective switching ■ 2.4V to 5.25V Adjustable Output Voltage frequency, minimizing inductor and capacitor sizes. True ■ Adjustable Current Limit output disconnect eliminates inrush current and allows ■ Adjustable, Fixed Frequency Operation from zero load current in shutdown. External Schottky diodes 100kHz to 2MHz per Phase are not required in most applications (VOUT < 4.3V). Power ■ Synchronizable Oscillator with Sync Output saving Burst Mode operation can be user controlled or left ■ Internal Synchronous Rectifiers in automatic mode. ■ Manual or Automatic Burst Mode® Operation Other features include 1µA shutdown current, program- ■ Power Good Comparator mable frequency with sync in and out, programmable ■ <1µA Shutdown Current soft-start, antiringing control, thermal shutdown, adjust- ■ Antiringing Control able current limit, reference output and power good ■ 5mm × 5mm Thermally Enhanced QFN Package
U
comparator.
APPLICATIO S
The LTC3425 is available in a small, thermally enhanced 32-pin QFN package. ■ Handheld Computers ■ Point-of-Load Regulators , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. ■ 3.3V to 5V Conversion
U TYPICAL APPLICATIO
VIN 2V TO 3V 2.2µF 2.7µH 2.7µH 2.7µH 2.7µH 100 VIN SWA SWB SWC SWD 90 VOUTS OFF ON SHDN VOUTA 80 Burst Mode FIXED VOUTB REFOUT 70 OPERATION FREQUENCY VOUTC VOUT MODE CCM VOUTD 3.3V 60 2A REFEN 4.7µF 50 LTC3425 ×4 1M 10k SYNCIN 40 FB 22pF EFFICIENCY (%) BURST 30 COMP 0.01µF V R IN = 2.4V T SS 330pF 590k 20 VOUT = 3.3V SYNCOUT f = 1MHz/PHASE 15k ILIM 10 PGOOD 33k L = 2.7µH 0 SGND GNDA GNDB GNDC GNDD 20k 75k 0.01µF 0.1 1 10 100 1000 10000 LOAD CURRENT (mA) 3425 TA01 3425 TA02 CIN: TAIYO YUDEN JMK107BJ225MA L1-L4: TDK RLF5018T-2R7M1R8 COUT: TAIYO YUDEN JMK212BJ475MG (×4) 3425f 1
U FEATURES DESCRIPTIO
■
High Efficiency: Up to 95%
The LTC®3425 is a synchronous, 4-phase boost converter ■
Up to 3A Continuous Output Current
with output disconnect capable of operation below 1V ■
4-Phase Operation for Low Output Ripple
input. It includes four N-channel MOSFET switches and
and Tiny Solution Size
four P-channel synchronous rectifiers for an effective ■
Output Disconnect and Inrush Current Limiting
RDS(ON) of 0.045Ω and 0.05Ω, respectively. 4-phase ■
Very Low Quiescent Current: 12
µ
A
operation greatly reduces peak inductor currents, and ■ 0.5V to 4.5V Input Range capacitor ripple current, and increases effective switching ■ 2.4V to 5.25V Adjustable Output Voltage frequency, minimizing inductor and capacitor sizes. True ■ Adjustable Current Limit output disconnect eliminates inrush current and allows ■ Adjustable, Fixed Frequency Operation from zero load current in shutdown. External Schottky diodes 100kHz to 2MHz per Phase are not required in most applications (VOUT < 4.3V). Power ■ Synchronizable Oscillator with Sync Output saving Burst Mode operation can be user controlled or left ■ Internal Synchronous Rectifiers in automatic mode. ■ Manual or Automatic Burst Mode® Operation Other features include 1µA shutdown current, program- ■ Power Good Comparator mable frequency with sync in and out, programmable ■ <1µA Shutdown Current soft-start, antiringing control, thermal shutdown, adjust- ■ Antiringing Control able current limit, reference output and power good ■ 5mm × 5mm Thermally Enhanced QFN Package
U
comparator.
APPLICATIO S
The LTC3425 is available in a small, thermally enhanced 32-pin QFN package. ■ Handheld Computers ■ Point-of-Load Regulators , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. ■ 3.3V to 5V Conversion
U TYPICAL APPLICATIO
VIN 2V TO 3V 2.2µF 2.7µH 2.7µH 2.7µH 2.7µH 100 VIN SWA SWB SWC SWD 90 VOUTS OFF ON SHDN VOUTA 80 Burst Mode FIXED VOUTB REFOUT 70 OPERATION FREQUENCY VOUTC VOUT MODE CCM VOUTD 3.3V 60 2A REFEN 4.7µF 50 LTC3425 ×4 1M 10k SYNCIN 40 FB 22pF EFFICIENCY (%) BURST 30 COMP 0.01µF V R IN = 2.4V T SS 330pF 590k 20 VOUT = 3.3V SYNCOUT f = 1MHz/PHASE 15k ILIM 10 PGOOD 33k L = 2.7µH 0 SGND GNDA GNDB GNDC GNDD 20k 75k 0.01µF 0.1 1 10 100 1000 10000 LOAD CURRENT (mA) 3425 TA01 3425 TA02 CIN: TAIYO YUDEN JMK107BJ225MA L1-L4: TDK RLF5018T-2R7M1R8 COUT: TAIYO YUDEN JMK212BJ475MG (×4) 3425f 1
