TM8000 3DK Hardware Developer’s Kit
Application Manual
Power Sense Options
123
September 2003
© Tait Electronics Ltd
7.1
13.8V Battery Power Sense
When this option is chosen and the radio is connected to power, the radio
will enter the programmed power-on mode. The on/off key can then be
used to turn the radio on and off.
This option has the disadvantage that when turned off (using the on/off
button) the radio still draws approx. 28mA because it enters stand-by mode
and does not shut down completely.
Note
The power consumption of the ‘no power sense’ option is <1 mA.
Applications
Use this option:
■
when the radio is used in a remote location (if the power is cut, the radio
does not need to be turned back on once power is restored)
■
when a control head is not fitted (no on/off key)
■
when the radio is used with a desktop supply with its own power switch
■
when wiring the positive power terminal of the radio directly to the
vehicle ignition (not recommended)
■
where the radio needs to be on or at least responsive at all times when
power is connected (emergency services)