Switch On/Off Circuit - GE MAC 1200 Service Manual

Switch On/Off Circuit

Device On Sequence
Device Off Sequence
2-8
Functional Description: PCB Control CS_CI
The Switch On/Off circuit consists of the On/Off control and the Voltage control.
The On/Off control switches the device on or off by switching the device supplies
+UVERS and +USUPPSW. The On/Off control is supplied from the +5 VSTB.
The transition from device Off state, or Standby state when line power is connected,
to device On state can only be activated by pressing the On/Off button.
The transition from device On state to device Off state or Standby state when line
power is connected can be achieved as follows.

Pressing the On/Off button.

When the control core activates the signal DEV_OFF.
 When the voltage control applies the signal REG_OFF_, because the battery
voltage gets too low during battery operation.
The Voltage Control controls the battery voltage during battery operation.
The signal BATT_LEV2 indicates that the battery charge has gone down, and the
device should be connected to the line power soon.
The signal BAT_LEV1 indicates that the battery has been discharged almost
completely, the device should be connected to the line power immediately,
otherwise the device will shut down within few minutes.
If battery discharge is continued without connecting to the line power, the signal
REG_OFF_ is activated and the device is switched off.
MAC 1200 resting ECG analysis system
2012250-095
Revision D