Low-Cost Voltage-Mode PWM

Step-Down Controllers

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3

ELECTRICAL CHARACTERISTICS (continued)

Note 1: Specifications to -40°C are guaranteed by design and not production tested.

Note 2: Thermal shutdown disables the buck regulator when the die reaches this temperature. Soft-start is reset and COMP/EN is

discharged to zero. In the MAX1967, the VL regulator remains on during thermal shutdown.

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

FB to COMP/EN

Transconductance

70

108

160

µS

FB Input Bias Current

3

100

nA

COMP/EN Source Current

15

46

100

µA

Current-Limit Threshold Voltage

(Across Low-Side NFET)

LX to GND

-340

-305

-270

mV

MOSFET DRIVERS

Break-Before-Make Time

30

ns

DH On-Resistance in Low State

1.6

4

Ω

DH On-Resistance in High State

2.5

5.5

Ω

DH Peak Source and Sink

Current

1

A

DL On-Resistance in Low State

1.1

2.5

Ω

DL On-Resistance in High State

2.5

5.5

Ω

DL Source Current

1

A

DL Sink Current

2

A

Maximum Total (DH + DL)

Average Source Current

25

mA

BST Leakage Current

0

50

µA

LX Leakage Current

33

100

µA