MC72000 Freescale Semiconductor, MC72000 Datasheet - Page 37

• Manufacturer Part Number: MC72000
• Description: Integrated Bluetooth Radio
• Manufacturer: Freescale Semiconductor

6.4 Transmitter
The MC72000 uses a direct launch transmitter taken from the output of the local oscillator (LO). During a
transmit cycle the VCO of the LO is automatically trimmed. Following the LO are the output power stages,
sequenced in the proper order. To minimize splattering, the output of the programmable low power
amplifier (LPA) drives a balanced ramp up/ramp down generator, which is fed to a “Balun” to provide a
single-ended output for the external antenna switch. The transmit start up/warm down sequences are
shown in Figure 30.
6.4.1 Transmit Synchronization Delay
A programmable delay exists between the rising edge of RTXEN and the first available bit of on-the-air
data during a transmit cycle. This delay range is TX
Synchronization Time Delay Value (R8/15-8) where the decimal value represents the delay in
microseconds. Packet data is seen at the antenna approximately 2.5 µs after this delay. All Bluetooth
packets require a minimum of four preamble bits of pattern 0101 or 1010. For minimum power
consumption, set the delay to TX
manipulate the delay as necessary, up to TX
MOTOROLA
Figure 15. C/I Performance for Channel 39 (2.405 GHz, High-Side Injection)
Freescale Semiconductor, Inc.
-10
-20
-30
-40
-50
-60
-10
-20
-30
-40
-50
-60
10
10
Figure 16. C/I Performance vs. Temperature
0
0
For More Information On This Product,
MC72000 Advance Information Data Sheet
-15
-3
sync
-1
T
minimum. If additional settling time or preamble bits are required,
A
-10
Go to: www.freescale.com
= 25° C
T
A
INTERFERER FREQUENCY DELTA (MHz)
1
INTERFERER FREQUENCY DELTA (MHz)
= -40° C
sync
-5
3
Preliminary
maximum.
sync
5
0
and is set via Radio Register Map bits of Transmit
T
7
A
= 85° C
5
9
11
10
13
Radio Functional Description
15
15
37