Gosuncn Technology Group Co. Ltd. GM500U1A Manual De Usuario
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GM500_U1A
Hardware Development Guide
2.4. P
OWER
S
UPPLY
2.4.1. P
OWER
S
UPPLY
P
INS
The GM500_U1A is supplied through the V_BAT signal with the following characteristics.
Table 2-4 Power Supply
Pin Name
Pin NO.
Description
Minimum
Typical
Maximum
Unit
V_BAT
50,51
Power supply for module
3.4
3.8
4.2
V
GND
3, 9, 11, 20, 21, 31, 36, 46,
49, 52, 61, 63, 78, 80,
Ground
-
-
GND signal (Pin No: 3/9/11/20/21/31/36/46/49/52/61/63/78/80) is the power and signal ground of the module, which needs
to be connected to the ground on the system board. If the GND signal is not connected completely, the performance of module will
be affected.
2.4.2. D
ECREASE
V
OLTAGE
D
ROP
The power supply range of the module is 3.4V~ 4.2V. In poor situation of the network is, the antenna will
transmit at the maximum power, and the transient maximum peak current can reach as high as 2A. So we
recommended to add Energy storage capacitor ( C6: 470μF). Filter capacitor(10µF, 0.1µF, 33pF) need to be added
to reduce interference. The capacitors should be placed close to the GM500_U1A’s V_BAT pins. The following
figure shows structure of the power supply.
recommended to add Energy storage capacitor ( C6: 470μF). Filter capacitor(10µF, 0.1µF, 33pF) need to be added
to reduce interference. The capacitors should be placed close to the GM500_U1A’s V_BAT pins. The following
figure shows structure of the power supply.
Figure 2–2 The input reference circuit of VBAT
The PCB traces from the V_BAT pins to the power source must be wide enough to ensure that there isn’t too
much voltage drop occurs in the transmitting procedure. The width of V_BAT trace should be no less than 2mm,
and the principle of the V_BAT trace is the longer, the wider.
and the principle of the V_BAT trace is the longer, the wider.
In addition, make the ground plane as complete as possible, and play more holes.
2.4.3. R
EFERENCE
C
IRCUIT OF
P
OWER
S
UPPLY
Option 1:DC-DC switching
The over-current capability requirement of DC/DC switching power supply needs to be above 2.5A. When the
input and output voltage difference is large, you need to select Buck circuit to improve translate efficiency.
Two reference power supply circuit design with DC-DC is shown as figure below: