8

FN9097.4

December 28, 2004

PIN-ADJUSTABLE OFFSET

Voltage at OFS pin

Offset resistor connected to ground

485

500

515

mV

VCC = 5.00V, offset resistor connected to VCC

2.91

3.00

3.09

V

OSCILLATOR

Accuracy

-10

-

10

%

Adjustment Range

0.08

-

1.5

MHz

Sawtooth Amplitude

-1.5

-

V

Max Duty Cycle

-

66.7

-

%

ERROR AMPLIFIER

Open-Loop Gain

-

80

-

dB

Open-Loop Bandwidth

-

18

-

MHz

Slew Rate

4.5

6.0

7.5

V/

µs

Maximum Output Voltage

4.0

4.3

-

V

Output High Voltage @ 2mA

3.7

-

-

V

Output Low Voltage @ 2mA

--

1.35

V

REMOTE-SENSE AMPLIFIER

Bandwidth

-20

-

MHz

Output High Current

VSEN - RGND = 2.5V

-500

-

500

µA

Output High Current

VSEN - RGND = 0.6

-500

-

500

µA

PWM OUTPUT

PWM Output Voltage LOW Threshold

Iload = ±500

µA

--

0.3

V

PWM Output Voltage HIGH Threshold

Iload = ±500

µA

4.3

-

-

V

TEMPERATURE COMPENSATION

Temperature Compensation Current @ 40

°C and

Tcomp = 0.5V

10

15

20

µA

Temperature Compensation Transconductance

-

1

-

1

µA/V/°C

SENSE CURRENT

Sensed Current Tolerance

ISEN1 = ISEN2 = ISEN3 = ISEN4 = 80

µA, 0°C to 105°C

74

81

91

µA

Overcurrent Trip Level

98

110

122

µA

POWER GOOD AND PROTECTION MONITORS

PGOOD Low Voltage

-

-

0.4

V

Undervoltage Offset From VID

VSEN Falling

72

74

76

%VID

Overvoltage Threshold

Voltage above VID, after Soft-Start (Note 5)

180

200

220

mV

Before Enable

-

1.63

-

V

VCC < POR Threshold

1.7

1.8

1.87

V

Overvoltage Reset Voltage

VCC

≥ POR Threshold, VSEN Falling

-

0.6

-

V

VCC < POR Threshold

-

1.5

-

V

OVP Drive Voltage

-

1.9

-

V

Minimum VCC for OVP

1.4

-

-

V

NOTES:

4. When using the internal shunt regulator, VCC is clamped to 6.02V (max). Current must be limited to 25mA or less.

5. These parts are designed and adjusted for accuracy with all errors in the voltage loop included.

6. During soft-start, VDAC rises from 0 to VID. The overvoltage trip level is the higher of 1.7V and VDAC + 0.2V.

Electrical Specifications

Unless Otherwise Specified. (Continued)

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

ISL6556B