BC352239A Datasheet, PDF (48/116 Pages) List of Unclassifed Manufacturers – BlueCore 3-Multimedia External

Device Terminal Descriptions
The persistent store key (PS Key) PSKEY_TX_GAINRAMP (0x1d), is used to control the delay (in units of µs)
between the end of the transmit power ramp and the start of modulation. In this period the carrier is transmitted,
which gives the transmit circuitry time to fully settle to the correct frequency.
Bits[15:8] define a delay, t_carrier, (in units of µs) between the end of the transmit power ramp and the start of
modulation. In this period the carrier is transmitted, which aids interoperability with some other vendor equipment
which is not strictly Bluetooth compliant.
8.1.8 Control of External RF Components
A PS Key TXRX_PIO_CONTROL (0x209) is used to control external RF components such as a switch, an
external PA or an external LNA. PIO[0], PIO[1] and the AUX_DAC can be used for this purpose, as indicated in
Table 8.3.
TXRX_PIO_CONTROL Value
0
1
2
3
4
AUX_DAC Use
PIO[0], PIO[1], AUX_DAC not used to control RF. Power ramping is
internal.
PIO[0] is high during RX, PIO[1] is high during TX. AUX_DAC not used.
Power ramping is internal.
PIO[0] is high during RX, PIO[1] is high during TX. AUX_DAC used to set
gain of external PA. Power ramping is external.
PIO[0] is low during RX, PIO[1] is low during TX. AUX_DAC used to set
gain of external PA. Power ramping is external.
PIO[0] is high during RX, PIO[1] is high during TX. AUX_DAC used to set
gain of external PA. Power ramping is internal.
Table 8.3: TXRX_PIO_CONTROL Values
BC352239A-ds-001Pc
© Cambridge Silicon Radio Limited 2004
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