UPD77533 datasheet(35/104 Pages) RENESAS

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Data Sheet S15671EJ4V0DS

µµµµPD77533

7.1

Shifting to Power Save Mode via Power Control Command

The Power Control command (CMD-ID: 0x03) (with STOP or HALT set in the data field) is used to shift the

µPD77533 to a power save mode (STOP or HALT). The flow of this transition is shown in Figure 7-2.

When the

µPD77533 receives the Power Control command (CMD-ID: 0x03), it shifts to the specified power save

mode after completing the following processing.

• Turning off the power of the RF block (RFON output signal = 0)

• Indicating externally that the status has been shifted to standby mode (STNDBYB output signal = 0: standby

mode)

Figure 7-2. Flow of Shifting to Standby Mode

7.2

Shifting to Power Save Mode via Sleep Timer Command

If the idle state (state in which signal processing

stopped

and

there

serial

command

transmission/reception) continues for the timeout period set by the Sleep Timer command (CMD-ID: 0x12), the

µPD77533 shifts to a power save mode (STOP or HALT). The mode to be shifted to is preset by the Sleep Timer

command (CMD-ID: 0x12).

Sleep timer setting/setting notification and sleep timer operation are described below.

7.2.1 Sleep timer setting

The sleep timer is set by the Sleep Timer command (CMD-ID: 0x12).

The mode to be shifted to (STOP or HALT) and the timer value at which the shift takes place are included in the

data field of the Sleep Timer command.

The Sleep Timer timeout value can be set within a range of 0 to 16777215 (0xFFFFFF) ms. Note, however, that if

0 ms is set, the

µPD77533 will not shift to a power save mode.

PD77533

Host CPU

RFON = 0 (off)

STNDBYB = 0 (standby)

"Power Control"

STOP or HALT

RUN

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