3

Date: 5/25/04

SP6137HV Dual Supply, Synchronous Buck Controller

© Copyright 2004 Sipex Corporation

PARAMETER

MIN

TYP

MAX

UNITS

♦

CONDITIONS

TIMERS: SOFTSTART

SS Charge Current:

10

µA

SS Discharge Current:

1

mA

♦

Fault Present, SS = 0.2V

PROTECTION: SHORT CIRCUIT & THERMAL

Short Circuit Threshold Voltage

0.2

0.25

0.3

V

♦

Hiccup Timeout

100

ms

Number of Allowable Clock Cycles

20

Cycles

at 100% Duty Cycle

Minimum GL Pulse After 20 Cycles

0.5

Cycles

Thermal Shutdown Temperature

145

°C

Thermal Recovery Temperature

135

°C

Thermal Hysteresis

10

°C

OUTPUT: NFET GATE DRIVERS

GH & GL Rise Times

35

50

ns

♦

Measured 10% to 90%

GH & GL Fall Times

30

40

ns

♦

Measured 90% to 10%

GL to GH Non Overlap Time

45

70

ns

♦

GH & GL Measured at 2.0V

SWN to GL Non Overlap Time

20

30

ns

♦

Measured SWN = 100mV to GL = 2.0V

GH & GL Pull Down Resistance

50

KΩ

ELECTRICAL SPECIFICATIONS: Continued

apply over the full operating temperature range, unless otherwise specified.

PIN DESCRIPTION

PIN #

PIN NAME DESCRIPTION

Bias Supply Input. Connect to external 5V supply. Used to power internal circuits and

low side gate driver.

2GL

High current driver output for the low side NFET switch. It is always low if GH is high or

during a fault. Resistor pull down ensure low state at low voltage.

3

GND

Ground Pin. The control circuitry of the IC and lower power driver are referenced to this

Feedback Voltage and Short Circuit Detection pin. It is the inverting input of the Error

Amplifier and serves as the output voltage feedback point for the Buck Converter. The

output voltage is sensed and can be adjusted through an external resistor divider.

and the IC enters hiccup mode.

5

COMP

Output of the Error Amplifier. It is internally connected to the non-inverting input of the

PWM comparator. An optimal filter combination is chosen and connected to this pin and

6

UVIN

minimum operating voltage.

7SS

Soft Start. Connect an external capacitor between SS and GND to set the soft start rate

based on the 10µA source current. The SS pin is held low via a 1mA (min) current during

all fault conditions.

8

SWN

Lower supply rail for the GH high-side gate driver. Connect this pin to the switching node

at the junction between the two external power MOSFET transistors.

9GH

High current driver output for the high side NFET switch. It is always low if GL is high or

during a fault. Resistor pull down ensure low state at low voltage.

10

BST

High side driver supply pin. Connect BST to the external boost diode and capacitor as

shown in the Typical Application Circuit on page 1. High side driver is connected between

BST pin and SWN pin.