The An8037 Power Supply Controller - Sony CPD-420GS Training Manual

The AN8037 Power Supply Controller

IC601
The heart or the primary section is the AN8037 Power Supply Controller,
IC601. The following table describes the function of each pin.
This is TR or Transform er R eset. Sim ilar to a dem agnetization function, this pin detects the falling edge
Pin 1 -
of the prim ary waveform during relaxation period.
TR
reaching the bottom of the ringing waveform .
O ver current protection. U sed to determ ine the overload level at w hich the tim er latch is activated.
Pin 2 -
O CP
O scillator. W ith a capacitor, determ ines the switching frequencies. (On/O ff tim es)
Pin 3 -
CF
O ver current protection. If the voltage on this pin (prim ary current feedback) exceeds -0.18V, the pow er
Pin 4 -
supply w ill enter cycle by cycle current lim iting m ode.
CLM
IC ground term inal.
Pin 5 -
G ND
O utput driver for switching transistor Q 602.
Pin 6 -
O UT
IC 601 supply voltage term inal. This voltage is norm ally +17.5V D C during 'A ctive O n' m ode and +12V
Pin 7 -
D C during 'A ctive O ff' and 'S uspend/Standby' m ode.
VC C
resistor R 613 until the auxiliary supply is available from T601 VC C w inding. If the voltage on this pin
exceeds +19.4V DC , O VP is activated and the power supply shuts off and can only be restarted by
disconnecting and reconnecting the A C line. Under voltage lock out (UV P) occurs w hen the voltage is
less than +9.5V DC .
U sed for the O VP and tim er latch functions. A capacitor determ ines the tim ing for O VP function.
Pin 8 -
SD
Feedback term inal.
Pin 9 -
FB
25
It allows the next conduction pulse only after
The IC receives starting current via startup