KA7500B.pdf

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KA7500B

SMPS Controller

Features

• Internal Regulator Provides a Stable 5V Reference Supply

Trimmed to 5%

• Uncommitted Output TR for 200mA Sink or Source

Current

• Output Control For Push-Pull or Single Ended Operation

• Variable Duty Cycle By Dead Time Control (Pin 4)

Complete PWM Control Circuit

• On-Chip Oscillator With Master or Slave Operation

• Internal Circuit Prohibits Double Pulse at Either Output

Description

The KA7500B is used for the control circuit of the PWM

switching regulator. The KA7500B consists of 5V reference

voltage circuit, two error amplifiers, a flip flop, an output

control circuit, a PWM comparator, a dead time comparator

and an oscillator. This device can be operated in the

switching frequency of 1 kHz to 300kHz.

16-DIP

16-SOP

Internal Block Diagram

Rev. 1.0.0

KA7500B

Absolute Maximum Ratings

Parameter

Symbol

Value

Unit

Supply Voltage

V CC

Collector Supply Voltage

V C

Output Current

I O

250

Amplifier Input Voltage

VIN

VCC +0.3

Power Dissipation (T A = 25

P D

1 (KA7500B)

0.9 (KA7500BD)

Operating Temperature Range

T OPR

0 ~ +70

Storage Temperature Range

TSTG

-65 ~ +150

KA7500B

Electrical Characteristics

(V CC = 20V, f = 10kHz, T A = 0

C to +70

C, unless otherwise specified)

Parameter

Symbol

Conditions

Min. Typ. Max. Unit

REFERENCE SECTION

Reference Output Voltage

V REF

I REF = 1mA

4.75

5.0

5.25

Line Regulation

V REF

V CC = 7V to 40V

2.0

Temperature Coefficient of V REF

V REF /

T A = 0

C to 70

0.01

0.03 %/

Load Regulation

V REF

I REF = 1mA to 10mA

1.0

Short-Circuit Output Current

I SC

V REF = 0V

OSCILLATOR SECTION

Oscillation Frequency

C T = 0.01

F, R T = 12k

kHz

Frequency Change with Temperature

T = 0.01

F, R T = 12k

DEAD TIME CONTROL SECTION

Input Bias Current

I BIAS

V CC = 15V, 0V

V 4

5.25V

-2.0

-10

Maximum Duty Cycle

D (MAX)

V CC = 15V, V 4 = 0V

O.C Pin = V REF

Input Threshold Voltage

V ITH

Zero Duty Cycle

3.0

3.3

Max. Duty Cycle

ERROR AMP SECTION

Input Offset Voltage

V IO

V 3 = 2.5V

2.0

Input Offset Current

I IO

V 3 = 2.5V

250

Input Bias Current

I BIAS

V 3 = 2.5V

0.2

1.0

Common Mode Input Voltage

V CM

V CC

40V

-0.3

V CC

Open-Loop Voltage Gain

G VO

0.5V

V 3

3 .5V

Unit-Gain Bandwidth (Note1)

650

PWM COMPARATOR SECTION

Input Threshold Voltage

V ITH

Zero Duty Cycle

4.5

Input Sink Current

I SINK

V 3 =0.7V

-0.3

-0.7

OUTPUT SECTION

Output Saturation Voltage

Common Emitter

V CE(SAT)

V E = 0, I C = 200mA

1.1

1.3

Common Collector

V CC(SAT)

V C = 15V, I E = -200mA

1.5

2.5

Collector Off-State Current

I C(OFF)

V CC = 40V, V CE = 40V

100

Emitter Off-State Current

I E(OFF)

V CC = V C = 40V, V E = 0

-100

TOTAL DEVICE

Supply Current

I CC

Pin 6 = V REF , V CC = 15V

OUTPUT SWITCHING CHARACTERISTICS

Rise Time

t R

Common Emitter

100

200

Common Collector

100

200

Fall Time

t F

Common Emitter

100

Common Collector

100

Note:

1. This parameter, although guaranteed, is not 100% tested in production.

KA7500B

Typical Application

Pulse Width Modulated Step-down Converter

V I =10V to 4 0V

KSA1010

1mH ,2 A

Vo=5V

Io=1A

150

0 .1uF

50uF

10V

5.1k

Vcc

COMP INPUT

- 2

V REF 14

5.1k

KA7500B

- 15

5.1k

+ 1

D.T

GND

O.C

R T

C T

+16

150

50uF

50V

50uF

10V

0.001uF

47k

GND

0.1

KA7500B

Mechanical Dimensions

Package

16-DIP

6.40 ±

0.20

0.252 ±

0.008

#16

7.62

0.300

3.25 ±

0.20

0.38

0.014

MIN

0.128 ±

0.008

5.08

0.200

MAX

3.30 ±

0.30

0.130 ±

0.012

–0.0 5

0.01 0 + 0.004

0.25 +0 .10

–0. 002

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