UCC2808-1, UCC2808-2, UCC3808-1, UCC3808-2

LOW POWER CURRENT MODE PUSH-PULL PWM

SLUS168D – APRIL 1999 – REVISED AUGUST 2002

4

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to 125

°C for the UCC1808–x, VDD = 10 V (See Note 6), 1 µF capacitor from VDD to GND, R = 22 kΩ, C = 330 pF,

output section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

OUT low level

I = 100 mA

0.5

1

V

OUT high level

I = –50 mA,

VDD – OUT

0.5

1

V

Rise time

CL = 1 nF

25

60

ns

Fall time

CL = 1 nF

25

60

ns

undervoltage lockout section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Start threshold

UCCx808–1,

See Note 6

11.5

12.5

13.5

V

Start threshold

UCCx808–2

4.1

4.3

4.5

V

Minim m operating oltage after start

UCCx808–1

7.6

8.3

9

V

Minimum operating voltage after start

UCCx808–2

3.9

4.1

4.3

V

H steresis

UCCx808–1

3.5

4.2

5.1

V

Hysteresis

UCCx808–2

0.1

0.2

0.3

V

soft start section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

COMP rise time

FB = 1.8 V,

rise from 0.5 V to 4 V

3.5

20

ms

overall section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Startup current

VDD < start threshold

130

260

µA

Operating supply current

FB = 0 V,

CS = 0 V,

See Note 5 and 6

1

2

mA

VDD zener shunt voltage

IDD = 10 mA,

See Note 4

13

14

15

V

NOTES:

1. Measured at RC. Signal amplitude tracks VDD.

2. Gain is defined by: A

+

DV

COMP

DV

CS

,0

v V

CS v

0.4 V,

3. Parameter measured at trip point of latch with FB at 0V.

4. Start threshold and zener shunt threshold track one another.

5. For UCCx808–1, set VDD above the start threshold before setting at 10 V.

6. Does not include current in the external oscillator network.