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LT1370

500kHz High Efficiency

6A Switching Regulator

The LT

switching regulator. It can be operated in all standard

switching configurations including boost, buck, flyback,

forward, inverting and “Cuk.” A 6A high efficiency switch

is included on the die, along with all oscillator, control and

protection circuitry.

The LT1370 typically consumes only 4.5mA quiescent

current and has higher efficiency than previous parts.

High frequency switching allows for very small inductors

to be used.

New design techniques increase flexibility and maintain

ease of use. Switching is easily synchronized to an exter-

nal logic level source. A logic low on the Shutdown pin

reduces supply current to 12

µA. Unique error amplifier

circuitry can regulate positive or negative output voltage

while maintaining simple frequency compensation tech-

niques. Nonlinear error amplifier transconductance

reduces output overshoot on start-up or overload recov-

ery. Oscillator frequency shifting protects external com-

ponents during overload conditions.

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Faster Switching with Increased Efficiency

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Uses Small Inductors: 4.7

µH

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All Surface Mount Components

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Low Minimum Supply Voltage: 2.7V

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Quiescent Current: 4.5mA Typ

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Current Limited Power Switch: 6A

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Regulates Positive or Negative Outputs

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Shutdown Supply Current: 12

µA Typ

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Easy External Synchronization

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Switch Resistance: 0.065

Ω Typ

FEATURES

, LTC and LT are registered trademarks of Linear Technology Corporation.

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Boost Regulators

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Laptop Computer Supplies

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Multiple Output Flyback Supplies

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Inverting Supplies

5V to 12V Boost Converter

LT1370

5V

GND

FB

LT1370 • TA01

S/S

L1*

C1**

22

µF

25V

C4**

22

µF

25V

× 2

C2

0.047

µF

C3

0.0047

µF

R3

2k

R2

6.19k

1%

R1

53.6k

1%

†

12V

D1

MBRD835L

ON

OFF

*

**

COILTRONICS

UP2-4R7 (4.7

µH)

UP4-100 (10

µH)

AVX TPSD226M025R0200

+

+

L1

4.7

µH

10

µH

1.8A

2A

OUT

12V Output Efficiency

LOAD CURRENT (A)

0

80

84

82

86

88

90

1.0 1.2 1.4 1.6 1.8

0.2 0.4 0.6 0.8

2.0

LT1370 • TA02

92

L = 10

µH