RT9986A Datasheet, PDF (5/24 Pages) Richtek Technology Corporation – 7-CH DC/DC Converter for DSC

Timing Diagram
Timing Diagram for CH1 to CH4
VDDM = Max
(BAT, PVDD1)
User define
EN1234
CH1 VOUT
CH3 VOUT
CH4 VOUT
CH2 VOUT
3.5ms
3.5ms
3.5ms
3.5ms
RT9986A
Wait until FB3 < 0.1V
Wait until FB4 < 0.1V
Wait until FB2 < 0.1V
CH5 and CH6 Power Sequence
The power on sequence is :
When EN56 goes high, CH5 will turn on first. After 10ms, CH6 will turn on.
The power off sequence is :
When EN56 goes low, CH6 will turn off first and VOUT6 will be internally pulled to GND.
When VOUT6 > −0.12V, CH6 discharging completes and then CH5 turns off. Finally, the whole IC shuts down.
Power On Sequence : CH5 HV Step-Up 15V → CH6 INV −7V
Power Off Sequence : CH6 INV −7V → CH5 HV Step-Up 15V
EN56
CH5
VOUT
CH6
VOUT
10ms
Constant Current
Pre-Charge.
10ms
Discharge by internal N-MOSFET
Wait until VOUT6 close to 0V
DS9986A-00 May 2011
www.richtek.com
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