Datasheet LT3430, LT3430-1 (Analog Devices)
| Fabricante | Analog Devices |
| Descripción | High Voltage, 3A, 200kHz/100kHz Step-Down Switching Regulators |
| Páginas / Página | 28 / 1 — FEATURES. DESCRIPTION. Wide Input Range: 5.5V to 60V. 3A Peak Switch … |
| Formato / tamaño de archivo | PDF / 335 Kb |
| Idioma del documento | Inglés |
FEATURES. DESCRIPTION. Wide Input Range: 5.5V to 60V. 3A Peak Switch Current over All Duty Cycles
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LT3430/LT3430-1 High Voltage, 3A, 200kHz/100kHz Step-Down Switching Regulators
FEATURES DESCRIPTION
■
Wide Input Range: 5.5V to 60V
The LT®3430/LT3430-1 are monolithic buck switching ■
3A Peak Switch Current over All Duty Cycles
regulators that accept input voltages up to 60V. A high ef- ■
Constant Switching Frequency:
fi ciency 3A, 0.1Ω switch is included on the die along with
200kHz (LT3430)
all the necessary oscillator, control and logic circuitry. A
100kHz (LT3430-1)
current mode architecture provides fast transient response ■ 0.1Ω Switch Resistance and excellent loop stability. ■ Current Mode Special design techniques and a new high voltage process ■ Effective Supply Current: 2.5mA achieve high effi ciency over a wide input range. Effi ciency ■ Shutdown Current: 30µA is maintained over a wide output current range by using ■ 1.2V Feedback Reference Voltage the output to bias the circuitry and by utilizing a supply ■ Easily Synchronizable boost capacitor to saturate the power switch. Patented ■ Cycle-by-Cycle Current Limiting circuitry* maintains peak switch current over the full duty ■ Small, 16-Pin Thermally Enhanced TSSOP Package cycle range. A shutdown pin reduces supply current to
APPLICATIONS
30µA and a SYNC pin can be externally synchronized with a logic level input from 228kHz to 700kHz for the LT3430 ■ Industrial and Automotive Power Supplies or from 125kHz to 250kHz for the LT3430-1. ■ Portable Computers The LT3430/LT3430-1 are available in a thermally enhanced ■ Battery Chargers 16-pin TSSOP package. ■ Distributed Power Systems , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. *US Patent # 6498466
TYPICAL APPLICATION 5V, 2A Buck Converter Effi ciency vs Load Current
100 MMSD914TI VOUT = 5V VIN = 12V 90 0.68µF BOOST V 22 IN µH VOUT 5.5V* VIN SW 5V 80 TO 60V 2A V 30BQ060 IN = 42V 4.7µF LT3430** 100V + 100µF 10V 70 SOLID OFF ON SHDN BIAS EFFICIENCY (%) TANTALUM 15.4k SYNC FB 60 LT3430-1 L = 68µH GND VC 4.99k LT3430 L =27µH 50 0 0.5 1.0 1.5 2.0 2.5 220pF LOAD CURRENT (A) 3.3k 3430 TA02 0.022µF 3430 TA01 *FOR INPUT VOLTAGES BELOW 7.5V, SOME RESTRICTIONS MAY APPLY ** SEE LT3430-1 CIRCUIT IN APPLICATIONS INFORMATION SECTION 34301fa 1
FEATURES DESCRIPTION
■
Wide Input Range: 5.5V to 60V
The LT®3430/LT3430-1 are monolithic buck switching ■
3A Peak Switch Current over All Duty Cycles
regulators that accept input voltages up to 60V. A high ef- ■
Constant Switching Frequency:
fi ciency 3A, 0.1Ω switch is included on the die along with
200kHz (LT3430)
all the necessary oscillator, control and logic circuitry. A
100kHz (LT3430-1)
current mode architecture provides fast transient response ■ 0.1Ω Switch Resistance and excellent loop stability. ■ Current Mode Special design techniques and a new high voltage process ■ Effective Supply Current: 2.5mA achieve high effi ciency over a wide input range. Effi ciency ■ Shutdown Current: 30µA is maintained over a wide output current range by using ■ 1.2V Feedback Reference Voltage the output to bias the circuitry and by utilizing a supply ■ Easily Synchronizable boost capacitor to saturate the power switch. Patented ■ Cycle-by-Cycle Current Limiting circuitry* maintains peak switch current over the full duty ■ Small, 16-Pin Thermally Enhanced TSSOP Package cycle range. A shutdown pin reduces supply current to
APPLICATIONS
30µA and a SYNC pin can be externally synchronized with a logic level input from 228kHz to 700kHz for the LT3430 ■ Industrial and Automotive Power Supplies or from 125kHz to 250kHz for the LT3430-1. ■ Portable Computers The LT3430/LT3430-1 are available in a thermally enhanced ■ Battery Chargers 16-pin TSSOP package. ■ Distributed Power Systems , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. *US Patent # 6498466
TYPICAL APPLICATION 5V, 2A Buck Converter Effi ciency vs Load Current
100 MMSD914TI VOUT = 5V VIN = 12V 90 0.68µF BOOST V 22 IN µH VOUT 5.5V* VIN SW 5V 80 TO 60V 2A V 30BQ060 IN = 42V 4.7µF LT3430** 100V + 100µF 10V 70 SOLID OFF ON SHDN BIAS EFFICIENCY (%) TANTALUM 15.4k SYNC FB 60 LT3430-1 L = 68µH GND VC 4.99k LT3430 L =27µH 50 0 0.5 1.0 1.5 2.0 2.5 220pF LOAD CURRENT (A) 3.3k 3430 TA02 0.022µF 3430 TA01 *FOR INPUT VOLTAGES BELOW 7.5V, SOME RESTRICTIONS MAY APPLY ** SEE LT3430-1 CIRCUIT IN APPLICATIONS INFORMATION SECTION 34301fa 1