Neo_M660A GPRS Module Hardware User Guide
Copyright © Neoway Technology Co., Ltd
22
3.6
Running LED Indicator
Table 3-6
LED indicator
Pin Name
I/O
Function
Remarks
LIGHT
DO
Indicates running status
2.8 V output, max. 4 mA
When the module is running, the LED indicator is driven by the LIGHT pin to indicate different module
status with its various blink behaviors. For how to set the LED indicator, see
Neo_M660A GPRS Module AT
Command Set
.
LIGHT can output 4 mA current and 2.8 V high level, therefore the LED can be directly connected to this
pin with a resistor in series. For better luminance, drive the LED with a transistor instead.
Figure 3-20
LED indicator directly driven by high level
LIGHT
GPRS
Module
1K
Figure 3-21
LED indicator driven by transistor
LIGHT
GPRS Module
10K
VCC
470 Ω
4.7K
