FAN7601_05 Datasheet, PDF (1/12 Pages) Fairchild Semiconductor – Green Current Mode PWM Controller

FAN7601
Green Current Mode PWM Controller
www.fairchildsemi.com
Features
• Green Current Mode PWM Control
• Low Operating Current: Max 4mA
• Burst Mode Operation
• Internal High Voltage Start-up Switch
• Under Voltage Lockout (UVLO): 12V/8V
• Latch Protection & Soft Start Function
• Over Voltage Protection: 19V
• Operating Frequency up to 300kHz
• Max Duty Cycle: 95%
Typical Applications
• Off-Line Adapter Applications
• Auxiliary Power Supplies
Description
The FAN7601 is a green programmable frequency current
mode PWM controller. It is specially designed for the
off-line adapter application and the auxiliary power supplies
which require high efficiency at a light load and no load.
The internal high voltage start-up switch and the burst mode
reduce the power loss. The FAN7601 includes some
protections such as latch protection and over voltage
protection. The latch protection can be used for over voltage
protection and/or thermal protection and so on. And the soft
start prevents the output voltage over shoot at start up.
10-SSOP 8-SOP
8-DIP
1
1
1
Internal Block Diagram
Vref (10)
8
Rt/Ct
(5)
4
OSC
Vref
12uA
Latch/SS
(4)
3
1.5V
OVP
+
−
2.5V
1V
GND
(6)
5
+
− _Start-up
Circuit
Vstr (1)
1
Enable
5V Ref
Start-up
Circuit
OVP ₊
−
7 ^Vcc
(8)
19V
UVLO ₊
−
12V/8V
SQ
R
OUT
6 ₍₇₎
SQ
R
Reset
Circuit
Delay Circuit
+
−
0.97V/0.9V
2 ^CS/FB
(3)
+
−
−
Latch/SS
1V
* ( ) is 10-SSOP PIN Number
©2005 Fairchild Semiconductor Corporation
Rev. 1.0.2