SAA8200HL Datasheet, PDF (53/71 Pages) NXP Semiconductors – Ensation Base integrated wireless audio baseband

Philips Semiconductors
SAA8200HL
Ensation Base integrated wireless audio baseband
7.21.3.3 Change from battery to USB supply
Figure 24 shows the timing diagram with a wireless transceiver changed to USB supply.
The USB supply has the priority. When the USB plug is disconnected the device goes to
the off state. In Idle mode the supplies DCDC_OUT1V8 and DCDC_OUT3V3 has still to
be present, but the LDOs have to deliver only a small current. The total device may not
draw more than 500 mA from the USB supply so a quiescent current of the few active
circuits has to be less then 100 mA each.
V_BAT(DCDC)
0
DCDC_ON
V_USB(DCDC)
supply transients from DCDC to LDO and LDO to off
DCDC_OUT3V3
DCDC_OUT1V8
0
SUPPLY_OK
RESET_B
V_USB__PRESENT
USB_DET
(internal iwab signal)
STOP
PLAY
PLAYDET
"V_USB"
Fig 24. Change from battery to USB supply
DCDC_OUT3V3 and DCDC_OUT1V8
001aac012
SAA8200HL_2
Preliminary data sheet
Rev. 02 — 17 October 2005
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
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