UCS1653S

Preliminary

LINEAR INTEGRATED CIRCUIT

UNISONICTECHNOLOGIESCO.,LTD

6 of 7

www.unisonic.com.tw

QW-R103-105.e



FUNCTIONAL DESCRIPTION(Cont.)

Fig.6 OLP case

FIG.7 OVP case

Drain

2.5V

470u

33n

15V

UTC

UCS1653S

470u

2

1

3

4

7

8

6

5

33n

IC3

15V

500Ω/1W

Fig.8 OLP test circuit

Fig.9 OVP test circuit

OTP

(7) Driver Output Section

The driver-stage drives the gate of the MOSFET and is optimized to minimize EMI and to provide high circuit

efficiency. This is done by reducing the switch on slope when reaching the MOSFET threshold. This is achieved by a

slope control of the rising edge at the driver’s output. The output driver is clamped by an internal 15V Zener diode in

order to protect power MOSFET transistors against undesirable gate over voltage.

(8) Inside power switch MOS transistor

Specific power MOS transistor parameter is as “POWER MOS TRANSISTOR SECTION” in electrical

characteristics table.