0°C < TA < +70°C; 0°C < TJ < +85°C; 8V < VCC1 < 14V; 5V < VCC2 < 14V; DAC Code: VID4 = VID2 = VID1
Electrical Characteristics:
= VID0 = 1; VID3 = 0; CVGATE(L) and CVGATE(H) = 1nF; COFF = 330pF; CSS = 0.1µF, unless otherwise specified.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
ꢀ PWM Comparator
Transient Response
VFFB = 0 to 5V to VGATE(H) = 9V to 1V;
100
0.3
125
ns
V
CC1 = VCC2 = 12V
VFFB Bias Current
VFFB = 0V
µA
ꢀ Supply Current
ICC1 No Switching
ICC2 No Switching
Operating ICC1
8.5
1.6
8
13.5
3.0
13
mA
mA
mA
mA
VFB = COMP = VFFB
VFB = COMP = VFFB
Operating ICC2
2
5
ꢀ COFF
Normal Charge Time
Extension Charge Time
Discharge Current
VFFB = 1.5V; VSS = 5V
1.0
5.0
5.0
1.6
8.0
2.2
11.0
µs
µs
mA
VSS = VFFB = 0
COFF to 5V; VFB >1V
ꢀ Time Out Timer
Time Out Time
VFB = VCOMP; VFFB = 2V;
Record VGATE(H) Pulse High Duration
VFFB = 0V
10
35
30
50
50
65
µs
%
Fault Mode Duty Cycle
Note 1: Guaranteed by design, not 100% tested in production.
Package Pin Description
PACKAGE PIN #
PIN SYMBOL
FUNCTION
16L SO Narrow
1,2,3,4,6
VID0 – VID4
Voltage ID DAC input pins. These pins are internally pulled up to 5V
providing logic ones if left open. VID4 selects the DAC range. When VID4
is High (logic one), the DAC range is 2.10V to 3.50V with 100mV incre-
ments. When VID4 is Low (logic zero), the DAC range is 1.30V to 2.05V
with 50mV increments. VID0 - VID4 select the desired DAC output volt-
age. Leaving all 5 DAC input pins open results in a DAC output voltage
of 1.2440V, allowing for adjustable output voltage, using a traditional
resistor divider.
5
SS
Soft Start Pin. A capacitor from this pin to LGnd in conjunction with
internal 60µA current source provides soft start function for the con-
troller. This pin disables fault detect function during Soft Start. When a
fault is detected, the soft start capacitor is slowly discharged by internal
2µA current source setting the time out before trying to restart the IC.
Charge/discharge current ratio of 30 sets the duty cycle for the IC when
the regulator output is shorted.
7
8
COFF
VFFB
A capacitor from this pin to ground sets the time duration for the on
board one shot, which is used for the constant off time architecture.
Fast feedback connection to the PWM comparator. This pin is connected
to the regulator output. The inner feedback loop terminates on time.
9
VCC2
Boosted power for the high side gate driver.
10
VGATE(H)
High FET driver pin capable of 1.5A peak switching current. Internal cir-
cuit prevents VGATE(H) and VGATE(L) from being in high state simultane-
ously.
4
CHERRY [ CHERRY SEMICONDUCTOR CORPORATION ]
