LT1507 查看數據表（PDF） - Linear Technology

零件编号

产品描述 (功能)

生产厂家

LT1507

500kHz Monolithic Buck Mode Switching Regulator

Linear Technology 

BLOCK DIAGRAM

VIN 2

BIAS

2.9V BIAS

REGULATOR

0.1Ω

+–

CURRENT

INTERNAL

VCC

SENSE

AMPLIFIER

VOLTAGE GAIN = 5

SLOPE COMP

SYNC 5

500kHz

OSCILLATOR

SHUTDOWN

COMPARATOR

+–

0.4V

SHDN 4

3.5µA

+

–

2.38V

LOCKOUT

COMPARATOR

Σ

0.9V

S

RS

FLIP-FLOP

+

R

–

CURRENT

COMPARATOR

FOLDBACK Q2

CURRENT

LIMIT

CLAMP

FREQUENCY

SHIFT CIRCUIT

8 VC

ERROR

AMPLIFIER

gm = 2000µmho

Figure 1. Block Diagram

LT1507

BOOST

1

DRIVER

CIRCUITRY

Q1

POWER

SWITCH

3 VSW

7 FB/SENSE

2.42V

6 GND

LT1507 • BD

APPLICATIONS INFORMATION

Note: This application section is adapted from the more

complete version found in the LT1375/LT1376 data sheet.

If more details are desired consult the LT1375/LT1376

Applications Information section, but please acquaint

yourself thoroughly with this LT1507 information first so

that differences between the LT1375 and the LT1507 do

not cause confusion.

FEEDBACK PIN FUNCTIONS

The feedback pin (FB or SENSE) on the LT1507 is used to

set output voltage and also to provide several overload

protection features. The first part of this section deals with

selecting resistors to set output voltage and the remaining

part talks about foldback frequency and current limiting

created by the FB pin. Please read both parts before

7

Share Link: