UC2843B

LINEAR INTEGRATED CIRCUIT

UNISONICTECHNOLOGIESCO.,LTD

4 of 8

www.unisonic.com.tw

QW-R103-048.D



ELECTRICAL CHARACTERISTICS(Cont.)

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX UNIT

OSCILLATOR SECTION

Frequency

Min =225 kHz, Max =275 kHz

49

52

55

kHz

48

56

kHz

Frequency Change with Voltage

V

∆

f

0.2

1

%

Frequency Change with

Temperature

T

∆

f

5

%

Oscillator Voltage Swing

Peak to peak

1.7

V

Discharge Current

7.8

8.3

8.8

mA

7.5

8.8

mA

ERROR-AMPLIFIER SECTION

Voltage Feedback Input

COMP =2.5V

2.45

2.5

2.55

V

Input Bias Current

-0.3

-1

μA

Open Loop Voltage Gain

65

90

dB

Unity Gain Bandwidth

0.7

1

MHz

Power Supply Rejection Ratio

PSRR

60

70

dB

Output Sink Current

2

6

mA

Output Source Current

-0.5

-0.8

mA

Output Voltage Swing High State

5

6

V

0.7

1.1

V

CURRENT-SENSE SECTION

Current Sense Input Voltage Gain

(Note 2,3)

2.85

3

3.15

V/V

Maximum Current Sense Input

Threshold

COMP =5V (Note 2)

0.9

1

1.1

V

Power Supply Rejection Ratio

PSRR

70

dB

Input Bias Current

-2

-10

μA

Propagation Delay

150

300

ns

OUTPUT SECTION

High-Level Output Voltage

13

13.5

V

12

13.5

V

Low-Level Output Voltage

0.1

0.4

V

1.5

2.2

V

Under-Voltage Lockout

Output Voltage

0.7

1.2

V

Output Voltage Rise Time

50

150

ns

Output Voltage Fall Time

50

150

ns

UNDERVOLTAGE-LOCKOUT SECTION

Startup Threshold

7.8

8.4

9

V

Minimum Operating Voltage

After Start-Up

7

7.6

8.2

V

PULSE-WIDTH MODULATOR SECTION

Maximum Duty Cycle

94

96

100

%

Minimum Duty Cycle

0

%

SUPPLY VOLTAGE

Power Startup Supply Current

0.3

0.5

mA

Power Operating Supply Current

11

17

mA

Power Supply Zener Voltage

30

34

V

2. Measured at the trip point of the latch, with VFB at 0V.