U3848/A/B/C

LINEAR INTEGRATED CIRCUIT

UNISONICTECHNOLOGIESCO.,LTD

5 of 13

www.unisonic.com.tw

QW-R103-033,B

PARAMETER

SYMBOL

RATINGS

UNIT

Supply Voltage

26

V

Input Voltage to FB Pin

-0.3 ~ 6.2

V

Input Voltage to CS Pin

-0.3 ~ 2.8

V

Input Voltage to RT Pin

-0.3 ~ 6.2

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

8.2 ~ 21

V

PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

SUPPLY SECTION

Start Up Current

27

45

µA

OFF

3.7

5.5

mA

Supply Current with switch

ON

4.0

6.0

mA

UNDER-VOLTAGE LOCKOUT SECTION

Start Threshold Voltage

11.8

12.6

13.4

V

Min. Operating Voltage

7.6

8.1

8.6

V

Hysteresis

4.5

V

INTERNAL VOLTAGE REFERENCE

Reference Voltage

6.1

6.3

6.6

V

CONTROL SECTION

U3848/B(Note1)

85

95

105

kHz

Normal

U3848A/C(Note2)

61

68

75

kHz

Switch Frequency

Power-Saving

17

20

23

kHz

MAX

65

70

75

%

Duty Cycle

MIN

0

%

MIN

0.5

V

MAX

4.4

V

Feedback Resistor

2.6

3.8

5.0

k

Ω

External Resistor for controlling Current

Source of OSC

75

k

Ω

6

ms

12

ms

Soft-Start Time

120

ms

PROTECTION SECTION

OVP threshold

15.2

16

16.8

V

OLP threshold

4.4

4.6

4.9

V

OTP threshold

120

135

150

°C

OVP Disable threshold

3.7

3.9

4.2

V

OLP Enable threshold

4.9

5.1

5.4

V

Spike Blanking time

7.2

µs

CURRENT LIMITING SECTION

LEB

220

ns