User's Manual

GE/GC864-QUAD V2 and GE864-GPS Hardware User Guide
1vv0300915 Rev.2 – 2011-06-15
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Reserved. Page 64 of 97
a possible translator circuit for a 5V TRANSMITTER/RECEIVER
can be:
TIP:
Note that the TC7SZ07AE has open drain output; therefore the
resistor R2 is mandatory.
NOTE:
The UART input line TXD (rx_uart) of the GE/GC864-QUAD V2 and
GE864-GPS NOT internally pulled up with a resistor, so there
may be the need to place an external 47KΩ pull-up resistor,
either the DTR (dtr_uart) and RTS (rts_uart) input lines are
not pulled up internally, so an external pull-up resistor of
47KΩ may be required.
Care must be taken to avoid latch-up on the GE/GC864-QUAD V2
and GE864-GPS and the use of this output line to power
electronic devices shall be avoided, especially for devices
that generate spikes and noise such as switching level
translators, micro controllers, failure in any of these
condition can severely compromise the GE/GC864-QUAD V2 and
GE864-GPS functionality.