AP3845S8 Anachip Corporation, AP3845S8 Datasheet - Page 4

• Manufacturer Part Number: AP3845S8
• Description: High Performance Current Mode PWM Controller
• Manufacturer: Anachip Corporation

High Performance Current Mode PWM Controller
Notes：2.These parameters, although guaranteed, are not 100% tested in production.
Figure 1 : Error Amp Configuration.
Figure 2 : Under Voltage Lockout.
During Under-Voltage Lockout, the output driver is biased to sink minor amounts of current. Pin 6 should be
shunted to ground with a bleeder resistor to prevent activating the power switch with extraneous leakage
currents.
Figure 3 : Current Sense Circuit.
Anachip Corp.
www.anachip.com.tw
3.Parameter measured at trip point of latch with V
4.Gain defined as:
5.Adjust V
6.Output frequency equals oscillator frequency for the AP3842 and AP3843.
7.Output frequency is one and half oscillator frequency for the AP3844 and AP3845.
A=
∆V
∆V
i
PIN1
PIN3
above the start threshold before setting at 15V.
; 0≦V
V
i
PIN3
7
Rs
≦0.8V
I
S
R
Zf
V
V
OFF
ON
ON/OFF COMMAND
TO REST OF IC
Error amp can source or sink up to 0.5mA
C
AP3842
AP3844
3
16V
10V
5
1
Zf
CURRENT
GND
SENSE
COMP
AP3843
AP3845
PIN2
8.4V
7.6V
COMP
=0.
V
ERROR
FB
AMP
2
1
4/8
<17 mA
<1 mA
2.5V
2R
I
CC
R
V
OFF
1V
V
ON
COMPARATOR
CURRENT
SENSE
AP3842/3/4/5
0.8 mA
V
CC
Rev.1.0 Oct.11, 2004