CS5156
Electrical Characteristics:
0°C < T
A
< +70°C; 0°C < T
J
< +85°C; 8V < V
CC1
< 14V; 5V < V
CC2
< 14V; DAC Code: V
ID4
= V
ID2
= V
ID1
= V
ID0
= 1; V
ID3
= 0; CV
GATE
= 1nF; C
OFF
= 330pF; C
SS
= 0.1µF, unless otherwise specified.
TEST CONDITIONS
MIN
TYP
PARAMETER
MAX
UNIT
s
Supply Current
I
CC1
I
CC2
Operating I
CC1
Operating I
CC2
No Switching
No Switching
V
FB
= COMP = V
FFB
V
FB
= COMP = V
FFB
8.5
1.6
8
2
13.5
3.0
13
5
mA
mA
mA
mA
s
C
OFF
Normal Charge Time
Extension Charge Time
Discharge Current
s
Time Out Timer
Time Out Time
Fault Mode Duty Cycle
V
FFB
= 1.5V; V
SS
= 5V
V
SS
= V
FFB
= 0
C
OFF
to 5V; V
FB
>1V
1.0
5.0
5.0
1.6
8.0
2.2
11.0
µs
µs
mA
V
FB
= V
COMP
; V
FFB
= 2V;
Record V
GATE
Pulse High Duration
V
FFB
= 0V
10
35
30
50
50
65
µs
%
Note 1: Guaranteed by design, not 100% tested in production.
Package Pin Description
PACKAGE PIN #
PIN SYMBOL
FUNCTION
16L SO Narrow & PDIP
1,2,3,4,6
V
ID0
– V
ID4
Voltage ID DAC input pins. These pins are internally pulled up to 5V
providing logic ones if left open. V
ID4
selects the DAC range. When V
ID4
is High (logic one), the DAC range is 2.14V to 3.54V with 100mV incre-
ments. When V
ID4
is Low (logic zero), the DAC range is 1.34V to 2.09V
with 50mV increments. V
ID0
- V
ID4
select the desired DAC output volt-
age. Leaving all 5 DAC input pins open results in a DAC output voltage
of 1.244V, allowing for adjustable output voltage, using a traditional
resistor divider.
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.
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.
Boosted power for the gate driver.
MOSFET driver pin capable of 1.5A peak switching current.
5
SS
7
8
9
10
C
OFF
V
FFB
V
CC2
V
GATE
4
CHERRY [ CHERRY SEMICONDUCTOR CORPORATION ]
