CS5157
Package Pin Description: continued
PACKAGE PIN #
PIN SYMBOL
FUNCTION
16L SO Narrow
11
PGnd
High current ground for the IC. The MOSFET drivers are referenced to
this pin. Input capacitor ground and the source of lower FET should be
tied to this pin.
Low FET driver pin capable of 1.5A peak switching current.
Input power for the IC and low side gate driver.
Signal ground for the IC. All control circuits are referenced to this pin.
Error amplifier compensation pin. A capacitor to ground should be
provided externally to compensate the amplifier.
Error amplifier DC feedback input. This is the master voltage feedback
which sets the output voltage. This pin can be connected directly to the
output or a remote sense trace.
12
13
14
15
16
V
GATE(L)
V
CC1
LGnd
COMP
V
FB
Block Diagram
V
CC2
V
CC1
-
+
3.90V
3.85V
V
CC1
Monitor
Comparator
5V
-
60µA
0.7V
+
SS Low
Comparator
R
S
Q
Q
V
GATE(H)
FAULT
FAULT
PGnd
SS
2µA
+
-
SS High
Comparator
FAULT
Latch
V
CC1
V
ID0
V
ID1
V
ID2
V
ID3
V
ID4
5 BIT
DAC
+
-
Error
Amplifier
2.5V
V
GATE(L)
PGnd
PWM
Comparator
-
GATE(H) = ON
GATE(H) = OFF
C
OFF
One Shot
R
S
Q
V
FB
COMP
V
FFB
Slow Feedback
+
Maximum
On-Time
Timeout
Normal
Off-Time
Timeout
R
S
Q
Q
PWM
Latch
Fast Feedback
-
+
Extended
Off-Time
Timeout
V
FFB
Low
Comparator
Off-Time
Timeout
C
OFF
LGnd
1V
PWM
COMP
Time Out
Timer
(30µs)
Edge Triggered
5