Datasheet LTC3429, LTC3429B (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 600mA, 500kHz Micropower Synchronous Boost Converter with Output Disconnect |
| Pages / Page | 12 / 1 — FEATURES. DESCRIPTIO. Up to 96% Efficiency. True Output Load Disconnect. … |
| File Format / Size | PDF / 204 Kb |
| Document Language | English |
FEATURES. DESCRIPTIO. Up to 96% Efficiency. True Output Load Disconnect. Inrush Current Limiting and Internal Soft-Start
Model Line for this Datasheet
Text Version of Document
LTC3429/LTC3429B 600mA, 500kHz Micropower Synchronous Boost Converter with Output Disconnect
U FEATURES DESCRIPTIO
■
Up to 96% Efficiency
The LTC®3429/LTC3429B are high efficiency synchro- ■
True Output Load Disconnect
nous, fixed frequency, step-up DC/DC converters with true ■
Inrush Current Limiting and Internal Soft-Start
output load disconnect, inrush current limiting and soft- ■
Low Voltage Start-Up: 0.85V
start in a low profile 6-lead ThinSOTTM package. These ■
Automatic Burst Mode® Operation with IQ ~ 20
µ
A
devices are capable of supplying 100mA from a single AA ■
Continuous Switching at Light Loads (LTC3429B)
cell input or 250mA from a 2-cell AA with a 3.3V output. ■
Internal Synchronous Rectifier
A switching frequency of 500kHz minimizes overall solu- ■
Current Mode Control with Internal Compensation
tion footprint by allowing the use of tiny, low profile ■
Short-Circuit Protection
inductors and ceramic capacitors. Current mode PWM ■ 500kHz Fixed Frequency Switching control with internal compensation reduces external parts ■ Input Range: 0.5V to 4.4V count thereby saving critical board real estate. The LTC3429 ■ Output Range: 2.5V to 4.3V (Up to 5V with Schottky) shifts automatically to power saving Burst Mode operation ■ Shutdown Current: <1µA at light loads while the LTC3429B features continuous ■ Antiringing Control Minimizes EMI switching at light loads. Antiringing control circuitry re- ■ Tiny External Components duces EMI concerns by damping the inductor in discon- ■ Low Profile (1mm) SOT-23 Package
U
tinuous mode.
APPLICATIO S
The devices also feature low shutdown current of under 1µA. The true output disconnect feature allows the output ■ MP3 Players to be completely discharged in shutdown. It also limits the ■ Digital Cameras inrush of current during start-up, minimizing surge cur- ■ LCD Bias Supplies rents seen by the input supply. ■ Handheld Instruments , LTC and LT are registered trademarks of Linear Technology Corporation. All other ■ Wireless Handsets trademarks are the property of their respective owners. Burst Mode is a registered ■ GPS Receivers trademark of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation.
U TYPICAL APPLICATIO 2-Cell to 3.3V Efficiency
100 100 VIN = 3V 4.7µH 90 EFFICIENCY 10 + 2-CELL V 4.7 POWER LOSS (W) µF IN = 2.4V AA SW V 80 1 OUT V V IN OUT 3.3V 250mA LTC3429 1.02M 70 VIN = 2.4V 0.1 OFF ON SHDN FB 10µF EFFICIENCY (%) 60 VIN = 3V 0.01 GND 604k POWER LOSS 50 0.001 3429 F01a 40 0.0001 0.1 1 10 100 1000
Figure 1. 2-Cell to 3.3V Synchronous Boost Converter
OUTPUT CURRENT (mA) 3429 F01b 3429fa 1
U FEATURES DESCRIPTIO
■
Up to 96% Efficiency
The LTC®3429/LTC3429B are high efficiency synchro- ■
True Output Load Disconnect
nous, fixed frequency, step-up DC/DC converters with true ■
Inrush Current Limiting and Internal Soft-Start
output load disconnect, inrush current limiting and soft- ■
Low Voltage Start-Up: 0.85V
start in a low profile 6-lead ThinSOTTM package. These ■
Automatic Burst Mode® Operation with IQ ~ 20
µ
A
devices are capable of supplying 100mA from a single AA ■
Continuous Switching at Light Loads (LTC3429B)
cell input or 250mA from a 2-cell AA with a 3.3V output. ■
Internal Synchronous Rectifier
A switching frequency of 500kHz minimizes overall solu- ■
Current Mode Control with Internal Compensation
tion footprint by allowing the use of tiny, low profile ■
Short-Circuit Protection
inductors and ceramic capacitors. Current mode PWM ■ 500kHz Fixed Frequency Switching control with internal compensation reduces external parts ■ Input Range: 0.5V to 4.4V count thereby saving critical board real estate. The LTC3429 ■ Output Range: 2.5V to 4.3V (Up to 5V with Schottky) shifts automatically to power saving Burst Mode operation ■ Shutdown Current: <1µA at light loads while the LTC3429B features continuous ■ Antiringing Control Minimizes EMI switching at light loads. Antiringing control circuitry re- ■ Tiny External Components duces EMI concerns by damping the inductor in discon- ■ Low Profile (1mm) SOT-23 Package
U
tinuous mode.
APPLICATIO S
The devices also feature low shutdown current of under 1µA. The true output disconnect feature allows the output ■ MP3 Players to be completely discharged in shutdown. It also limits the ■ Digital Cameras inrush of current during start-up, minimizing surge cur- ■ LCD Bias Supplies rents seen by the input supply. ■ Handheld Instruments , LTC and LT are registered trademarks of Linear Technology Corporation. All other ■ Wireless Handsets trademarks are the property of their respective owners. Burst Mode is a registered ■ GPS Receivers trademark of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation.
U TYPICAL APPLICATIO 2-Cell to 3.3V Efficiency
100 100 VIN = 3V 4.7µH 90 EFFICIENCY 10 + 2-CELL V 4.7 POWER LOSS (W) µF IN = 2.4V AA SW V 80 1 OUT V V IN OUT 3.3V 250mA LTC3429 1.02M 70 VIN = 2.4V 0.1 OFF ON SHDN FB 10µF EFFICIENCY (%) 60 VIN = 3V 0.01 GND 604k POWER LOSS 50 0.001 3429 F01a 40 0.0001 0.1 1 10 100 1000
Figure 1. 2-Cell to 3.3V Synchronous Boost Converter
OUTPUT CURRENT (mA) 3429 F01b 3429fa 1
