BC41B143A-DS-001PE Datasheet, PDF (53/102 Pages) List of Unclassifed Manufacturers – BlueCpre 4-ROM Single Chip Bluetooth v2.0 System with EDR

Device Terminal Descriptions
TX Power
Modulation
t_carrier
Figure 10.3: Internal Power Ramping
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.
10.1.4 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 10.1.
TXRX_PIO_CONTROL Value AUX_DAC Use
0
PIO[0], PIO[1], AUX_DAC not used to control RF. Power ramping is
internal.
1
PIO[0] is high during RX, PIO[1] is high during TX. AUX_DAC not used.
Power ramping is internal.
2
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.
3
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.
4
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 10.1: TXRX_PIO_CONTROL Values
BC41B143A-ds-001Pe
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