UC3875C

Preliminary

LINEAR INTEGRATED CIRCUIT

UNISONICTECHNOLOGIESCO.,LTD

4 of 9

www.unisonic.com.tw

QW-R103-075.b



PARAMETER

SYMBOL

RATINGS

UNIT

Supply Voltage

30

V

Input Voltage to FB Pin

-0.3~7

V

Input Voltage to CS Pin

-0.3~7

V

Junction Temperature

+150

C

Operating Temperature

-40~+125

°C

Storage Temperature

-50~+150

C

Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.

Absolute maximum ratings are stress ratings only and functional device operation is not implied.



OPERATING RANGE

PARAMETER

SYMBOL

RATINGS

UNIT

Supply Voltage

10~26

V



PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

HV START

Supply Current from ST Pin

2

2.8

5

mA

Start Pin Leakage Current After Startup

10

μA

SUPPLY SECTION

Start Up Current

0.8

20

μA

IC Operating current

0.6

5

mA

VDD Zener Clamp current

15

mA

UNDER-VOLTAGE LOCKOUT SECTION

Start Threshold Voltage

11

12

13

V

Min. Operating Voltage

6

7

8

V

CONTROL SECTION

5.1

V

PWM Input Gain

3

V/V

Burst-Mode Out FB Voltage

1.4

V

Reduce-Frequency end FB Voltage

2.2

V

Burst-Mode Enter FB Voltage

1.1

V

Normal

60

65

70

KHz

Switch Frequency

Power-Saving

Before enter burst mode

22

KHz

Duty Cycle

75

%

Frequency Hopping

-4

+4

%

Frequency VDD Stability

5

%

Frequency Temperature Stability

T=-20~100°C

1.5

5

%

RI Resistor Value Range

50

100

150

KΩ

Feedback Resistor

25

KΩ

PROTECTION SECTION

VCC Over Voltage Protection Threshold

27

V

FB PIN Over Load Protection Threshold

4

4.2

4.4

V

Over Load Protection Delay-Time

75

mS

OTP threshold

160

°C

CURRENT LIMITING SECTION

Over Current Flat Threshold Voltage

0.6

0.7

0.8

V

Lead Edge Blanking Time

350

ns

DRIVER OUTPUT SECTION

Output Voltage Low State

0.8

V

Output Voltage High State

11

V

Output Voltage Rise Time

100

ns

Output Voltage Fall Time

60

ns