Current

Sense

Comparator

PWM

Latch

GND

Output

V

C

V

5 V

50 mA

REF

V

CC

GND

R /C

T

T

V

FB

COMP

I

SENSE

Internal

Bias

S/R

5-V

REF

V

Good

Logic

REF

UVLO

34 V

2.5 V

Osc

Error

Amp

S

R

2R

R

1 V

7

5

4

2

1

3

5

6

7

8

ABSOLUTE MAXIMUM RATINGS

(1) (2)

UC2843A-Q1

FUNCTIONAL BLOCK DIAGRAM

over operating free-air temperature range (unless otherwise noted)

VALUE

UNIT

30

V

Self limiting

Output current

±1

A

Output energy (capacitive load)

5

µJ

Analog inputs (pins 3 and 5)

–0.3 to 6.3

V

Error amplifier output sink current

10

mA

1

W

θ

JA

97

°C/W

Storage temperature range

–65 to 150

°C

Lead temperature soldering 1,6 mm (1/16 inch) from case for 10 seconds

260

°C

(1)

Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings

only, and functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating

Conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(2)

Unless otherwise indicated, voltages are reference to ground, and currents are positive into and negative out of the specified terminals.

(3)

Long-term high-temperature storage and/or extended use at maximum recommended operating conditions may result in a reduction of

overall device life. See http://www.ti.com/ep_quality for additional information on enhanced plastic packaging.

2

Submit Documentation Feedback

Copyright © 2008, Texas Instruments Incorporated

Product Folder Link(s): UC2843A-Q1