7
MEB-1000 User Manual
1.8 Application Circuit
Figure 4 Application Circuit
Note:
(1) Serial Interface:
(
Ⅰ
)The TXA & RXA pin is recommended to connect to serial resistance(220
Ω
) and pull up (10K
Ω
). It can increase the stability of serial data.
(
Ⅱ
)The TXB & RXB pin is recommended to connect to serial resistance(220
Ω
) and pull up (10K
Ω
), if use the DGPS output.
If no use DGPS output, it don’t connect anything.
(2) Backup Battery:
It’s recommended to connect a backup battery to V_RTC_3V3.
In order to enable the warm start and hot start features of the GPS receiver.
If you don’t intend to use a backup battery, connect this pin to GND or open.
If you use backup battery, should be add a bypassing capacitor (10uF) at
V_RTC_3V3 pin. It can reduce noise and increase the stability.
(3) GPS_RF_IN:
Connecting to the antenna has to be routed on the PCB. The transmission
line must to controlled impedance to connect RF_IN to the antenna or
antenna connector of your choice. (Impedance 50
Ω
)
(4) Power:
Connect V_GPS_3V3 pin to DC 3.3V. The power supply must add bypassing