User's Manual

PCS3_HD_v01.000-03
Confidential / Preliminary
Page 32 of 101
2013-10-21
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PCS3 Hardware Interface Description
3.3 Power-Up / Power-Down Scenarios
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3.3.7 Turn off PCS3 in Case of Emergency
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Caution: Use the EMERG_OFF line only when, due to serious problems, the software is not
responding for more than 5 seconds. Pulling the EMERG_OFF line causes the loss of all
information stored in the volatile memory. Therefore, this procedure is intended only for use in
case
of emergency, e.g. if PCS3 does not respond, if reset or shutdown via AT command fails.
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The EMERG_OFF line is available on the application interface and can be used to switch off
the module. To control the EMERG_OFF line it is recommended to use an open drain / collector
driver.
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To switch off, the EMERG_OFF line must be pulled to ground for longer than 40ms. After the
40ms and an additional delay period of 500ms the module shuts down as shown in Figure 7.
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BATT+
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Shut Down
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PWR_IND
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EMERG_OFF >40ms
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VEXT
40ms
500ms
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Figure 7: Shutdown by EMERG_OFF signal
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Please note that the power supply voltage (BATT+) may be disconnected resp. switched off
only after having reached Shut Down as indicated by the PWR_IND signal going high. The
power supply has to be available (again) before the module is restarted.