MC45 Hardware Interface Description
P R E L I M I N A R Y
MC45_HD_01_V00.02a
Page 58 of 90
12.08.2002
3.8.2 Outputs
3.8.2.1 Synchronization signal
The synchronization signal serves to indicate growing power consumption during the
transmit burst. The signal is generated by the SYNC pin (pin number 32). Please note that
this pin can adopt two different operating modes which you can select by using the
AT^SSYNC command (mode 0 and 1). For details refer to the following chapter and to the
"AT Command Set".
To generate the synchronization signal the pin needs to be configured to mode 0 (= default).
This setting is recommended if you want your application to use the synchronization signal
for better power supply control. Your platform design must be such that the incoming signal
accommodates sufficient power supply to the MC45 module if required. This can be
achieved by lowering the current drawn from other components installed in your application.
The characteristics of the synchronization signal are explained below.
Table 16: MC45 synchronization signal (if SYNC pin is set to mode 0 via AT^SSYNC)
Function
Pin
Pin status
Description
Low
No operation
Synchronization
SYNC
High
Indicates increased power consumption
during transmission.
Figure 22: SYNC signal during transmit burst
*)
The duration of the SYNC signal is always equal, no matter whether the traffic or the
access burst are active.
Transmit burst
1 Tx 577 µs every 4.616 ms
2 Tx 1154 µs every 4.616 ms
300 µs
SYNC signal
*)
