User Guide

All Rights reserved, No Spreading abroad without GOSUNCN Permission
17
GM500-U1G_A
Hardware Development Guide
Table 2-1 IO Parameters Definition
Type Description
IO Bidirectional input/output
DI Digital input
DO Digital output
PI Power input
PO Power output
AI Analog input
AO Analog output
OD Open drain
The logic levels are described in the following table.
Table 2-2 Logic levels Description
Parameter Min Max Unit
VIH 0.65*VDD_IO VDD_IO+0.3 V
VIL -0.3 0.35* VDD_IO V
VOH VDD_IO-0.45 VDD_IO V
VOL 0 0.45 V
NOTE:
VDD_IO is the voltage level of pins.
The following tables show the GM500-U1G_A’s pin definition.
Table 2-3 Pin Description
Pin Name Pin NO. I/O Description DC Characteristics Comment
RF Interface
MAIN_ANT 62 IO Main antenna 50Ω impedance
DIV_ANT 79 AI Diversity antenna 50Ω impedance
GNSS_ANT 10 IO GNSS antenna 50Ω impedance
Power Supply
Pin Name Pin NO. I/O Description DC Characteristics Comment
VBAT 50.51 PI Power supply for
module
Vmax = 4.2V
Vmin = 3.4V
Vnorm = 3.8V
It must be able to provide sufficient
current in a transmitting burst which
typically rises to 2.0A
VREF_1V8 5 PO Provide 1.8V for
external circuit
Vnorm = 1.8V
Imax = 50mA
Power supply for external GPIO’S pull
up circuits
PLL_1V8 4 PO
Provide 1.8V for
external circuit
Vnorm = 1.8V
Imax = 20mA
This pin can only be used for WiFi
interface, and can left unconnected
when not used.
GND 3,9,11,20,21,31,36,
46,49,52,61,63,78,
80,81,87~102,107,
Ground