UCC2919

UCC3919

SLUS374C − JULY 1999 − REVISED NOVEMBER 2005

5

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SD and L/R inputs

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Input voltage low

0.8

V

Input voltage high

2

V

L/R input current

1

3

6

µA

SD internal pulldown impedance

100

270

500

k

Ω

FLT output

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Output leakage current

VDD = 5 V

10

µA

Output low voltage

IOUT = 10 mA

1

V

FET gate driver and charge pump

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Peak output current

VCAP = 15 V,

VGATE = 10 V

–3

–1

–0.25

mA

Peak sink current

VGATE = 5 V

20

mA

Fault delay

100

300

ns

Maximum output voltage

VDD = 3 V,

average IOUT = 1 µA

8

10

12

V

Maximum output voltage

VDD = 8 V,

average IOUT = 1 µA

12

14

16

V

Charge pump UVLO minimum voltage

VDD = 3 V

6.5

8.8

10.1

V

Charge pump UVLO minimum voltage

to start

VDD = 8 V

6.5

9.9

11.5

V

Charge pump source impedance

VDD = 5 V,

average IOUT = 1 µA

50

100

150

k

Ω

pin descriptions

CAP

A capacitor is placed from this pin to ground to filter the output of the on board charge pump. A 0.01-

µF to 0.1-µF

capacitor will work in most applications. Refer to TI literature number SLUA339 application note, Sizing the

UCC3919 Charge−Pump Capacitor, to determine the exact capacitance.

CSN

The negative current sense input signal.

CSP

The positive current sense input signal. Input to the duty cycle timer.

CT

Input to the duty cycle timer. A capacitor is connected from this pin to ground, setting the off time and maximum

on time of the over-current protection circuit.

FLT

Fault indicator. This open drain output will pull low under any fault condition where the output driver is disabled.

This output is disabled when the IC is in low current standby mode.