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

LOW POWER CURRENT MODE PUSH-PULL PWM

SLUS168D – APRIL 1999 – REVISED AUGUST 2002

3

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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,

oscillator section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Oscillator frequency

175

194

213

kHz

Oscillator amplitude/VDD

See Note 1

0.44

0.5

0.56

V/V

error amplifier section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Input voltage

COMP = 2 V

1.95

2

2.05

V

Input bias current

–1

1

µA

Open loop voltage gain

60

80

dB

COMP sink current

FB = 2.2 V,

COMP = 1 V

0.3

2.5

mA

COMP source current

FB = 1.3 V,

COMP = 3.5 V

–0.2

–0.5

mA

PWM section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Maximum duty cycle

Measured at OUTA or OUTB

48%

49%

50%

Minimum duty cycle

COMP = 0 V

0%

current sense section

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Gain

See Note 2

1.9

2.2

2.5

V/V

Maximum input signal

COMP = 5 V,

See Note 3

0.45

0.5

0.55

V

CS to output delay

COMP = 3.5 V,

CS from 0 to 600 mV

100

200

ns

CS source current

–200

nA

Over current threshold

0.7

0.75

0.8

V

COMP to CS offset

CS = 0 V

0.35

0.8

1.2

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.