YGV639 Datasheet, PDF (18/34 Pages) YAMAHA CORPORATION – Video Controller 1 with Enhanced Functions

YGV639
Power Regulator Pins for Core
VC1E has the built in regulator for core power supply. And over current protection circuit to detect a short
circuit is also incorporated.
Over Current Protection Circuit Reset Pin
OCPEN (Input)
Enables/Disables the operation of the over current protection circuit.
● “H” input: Enable operation of over current protection circuit.
● “L” input: Disable operation of over current protection circuit.
This signal shuts down the power supply regulator output temporarily when detecting an over-current
condition.
OCPEN functions as the reset signal of the over current protection circuit. When “L” is input to OCPEN,
power is supplied again.
Over Current Protection Circuit Enable Pin
TEST_REG (Input)
This is the test pin for the over current protection circuit. Normally, this pin should be used with it held to
“L.”
Output of Over Current Detection State
OCP_N (Output)
This signal indicates the state of the over current protection circuit. Connect this pin to a CPU port etc. to
monitor its state.
● “L” output: The regulator shuts down the core power supply by detecting an over current
condition.
● “H” output: The regulator outputs the power as normal operation.
OCP_N pin becomes “L” level when the voltage of the core power supply output pin VOUT18 is low,
such as at power-on or power supply recovery from the shutdown state due to overcurrent detection, etc.
Capacitor Connection Pin for Core Power Supply
VDDCORE
The decoupling capacitor connection pins for core power supply. Connect a 4.7μF ceramic capacitor
between VDDCORE and GND. Put the capacitor as close to VDDCORE pin as possible.
Note: Do not supply power to this VDDCORE pin.
1.8V Power Output Pin
VOUT18 (Output)
1.8V-power-supply regulator output pin. Connect it to PLLVDD pin. Connect a 4.7μF ceramic capacitor
between VOUT18 and GND. Put the capacitor as close to VOUT18 pin as possible.
18