[AK4204]
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Video Circuit Power-Up Sequence
The video circuit of the AK4204 is powered-up when the VPDN pin becomes “H”.
(Note) The charge pump starts operation when the VPDN pin or APDN pin is “H”.
The figure below shows an example of when the APDN pin becoes “H” before the VPDN pin.
Power Supply
VDD1,VDD2
VPDN
Charge Pump
VEE
3.0V
APDN: “L”
→
“H” (Note)
Power down VEE=0V
Power up VEE = Negative voltage
Video Circuit
Video Timer
Circuit
Power down
Power up
(1)
time B
VIN
VOUT
VSS2=0V
Video Input Signal
(2)
Video Output Signal
VSS2=0V
Figure 7. System Reset Diagram
(1) When the VPDN pin goes to “H”, the video timer circuit starts counting “timeB” period (max. 100ms).
(2) After the “timeB” period, the video output becomes ebable exiting 0V state.
Rev. 0.1
-9-
2012/02
AKM [ ASAHI KASEI MICROSYSTEMS ]
