W7020 Datasheet, PDF (23/36 Pages) List of Unclassifed Manufacturers – Bluetooth Radio Module

Preliminary Data Sheet
September 2000
W7020 Bluetooth Radio Module
Transmit and Receiver Application (continued)
Timing Information
Figure 9 shows the test conditions required to produce a transmit and receive slot with the W7020. (In addition,
pins POR_EXT and SYS_CLK_REQ must be held HIGH.)
The transmit slot begins with taking SYNT_ON HIGH. This turns on the synthesizer and voltage-controlled
oscillator (VCO). The synthesizer is programmed to the appropriate channel (see the Channel Register
Programming Example section). A delay (tTO) is required for the phase-lock loop (PLL) to settle before TX_ON is
pulled HIGH. Modulation is achieved by first opening the PLL by taking PHD_OFF high. The transmit data from
the baseband device is input into the W7020 TX_DATA pin. The W7020 Gaussian filter shapes the data, and
then directly modulates the VCO. After the transmit slot is completed, the TX_ON, PHD_OFF, and SYNT_ON
inputs are returned to a LOW for minimum current consumption.
TX SLOT
TX_DATA
tTD
RX_DATA
tRD
PHD_OFF
TX_ON
RX_ON
PX_ON
SYNT_ON
SI_CDI
CHANNEL
NUMBER
tTO
tPHD
CHANNEL
NUMBER
tTX
tRO
ts
Figure 9. Timing Diagram
RX SLOT
tRX
ts
Lucent Technologies Inc.
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