MAX-8 / MAX-M8 - Hardware Integration Manual
UBX-15030059 - R05
Design
Page 17 of 31
Production Information
Figure 14: Schematic of open circuit detection (for exact pin orientation, see the
MAX-M8 Data Sheet
[2])
RF
Vcc
Rbias
R
R
R
I
_
3
2
2
•
+
=
Equation 1: Calculation of threshold current for open circuit detection
☞
Antenna open circuit detection (
ANT_DET
) is not activated by default. It can be enabled by the
UBX-CFG-ANT message. This configuration must be sent to the receiver at every startup.
To enable the Antenna open circuit detection feature, the following command must be sent to the
receiver at every startup:
“B5 62 06 13 04 00 1F 00 F0 B5 E1 DE”.
"high" = Antenna detected (antenna consumes current); "low" = Antenna not detected (no
current drawn).
For more information about how to implement and configure OCD, see the
u-blox 8 / u-blox M8
Receiver Description Including Protocol Specification [3].
☞
If the antenna supply voltage is not derived from VCC_RF, do not exceed the maximum voltage
rating of
ANT_DET
.
