LT1432-3.3 Просмотр технического описания (PDF) - Linear Technology

Номер в каталоге

Компоненты Описание

производитель

LT1432-3.3

3.3V High Efficiency Step-Down Switching Regulator Controller

Linear Technology 

LT1432-3.3

APPLICATI S I FOR ATIO

normal mode, then switching to normal mode, pausing for

1ms, followed by return to full load.

If this sequence is not possible, an alternative is to

increase the output capacitor to > 680µF. This modifica-

tion will often allow the power-down sequence to consist

of simultaneous turn-off of load current and switch to

Burst Mode operation. Power-up is accomplished by

switching to normal mode and simultaneously increasing

load current to the lowest possible value (30mA to 500mA),

followed by a short pause and return to full load current.

Full Shutdown

When the Mode pin is driven high, full shutdown of the

regulator occurs. Regulator input current will then consist

of the LT1432 shutdown current (≈15µA) plus the switch

leakage of the switching IC (≈1µA to 25µA). Mode input

current (≈15µA at 5V) must also be considered. Start-up

from shutdown can be in either normal or Burst Mode

operation, but one should always check start-up over-

shoot, especially if the output capacitor or frequency

compensation components have been changed.

U

PACKAGE DESCRIPTIO Dimensions in inches (millimeters) unless otherwise noted.

0.300 – 0.325

(7.620 – 8.255)

N8 Package

8-Lead Plastic DIP

0.045 – 0.065

(1.143 – 1.651)

0.130 ± 0.005

(3.302 ± 0.127)

0.009 – 0.015

(0.229 – 0.381)

+0.025

0.325 –0.015

( ) 8.255

+0.635

–0.381

0.065

(1.651)

TYP

0.005

(0.127)

MIN

0.100 ± 0.010

(2.540 ± 0.254)

0.125

(3.175)

MIN

0.015

(0.380)

MIN

0.255 ± 0.015*

(6.477 ± 0.381)

0.018 ± 0.003

(0.457 ± 0.076)

*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.

MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)

0.400*

(10.160)

MAX

8

7

6

5

12

34

N8 0695

S8 Package

8-Lead Plastic SOIC

0.010

(0.254

–

–

0.020

0.508)

×

45°

0.008 – 0.010

(0.203 – 0.254)

0.053 – 0.069

(1.346 – 1.752)

0°– 8° TYP

0.016 – 0.050

0.406 – 1.270

0.014 – 0.019

(0.355 – 0.483)

*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH

SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE

**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD

FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE

0.004 – 0.010

(0.101 – 0.254)

0.228 – 0.244

(5.791 – 6.197)

0.050

(1.270)

BSC

0.189 – 0.197*

(4.801 – 5.004)

8

7

6

5

1

2

34

0.150 – 0.157**

(3.810 – 3.988)

SO8 0695

RELATED PARTS

PART NUMBER

LTC1148

LT1432

LT1507

DESCRIPTION

High Efficiency Step-Down Switching Regulator Controller

High Efficiency Synchronous Step-Down Switching Regulator

1.5A, 500kHz Step-Down Switching Regulator

COMMENTS

5V Regulated Output Voltage

Adjustable and Fixed 5V or 3.3V Outputs

Fixed Frequency PWM for Low Input Voltages from 4.5V to 12V

8

Linear Technology Corporation

1630 McCarthy Blvd., Milpitas, CA 95035-7487

(408) 432-1900 q FAX: (408) 434-0507 q TELEX: 499-3977

LT/GP 0895 2K REV A • PRINTED IN USA

© LINEAR TECHNOLOGY CORPORATION 1992

Share Link: