Decode Led - Newland NLS-EM1300-LD Integration Manual

Decode LED

The EM1300-LD provides a pin (LED, PIN 10) on the host interface connector that can be used by an
external driver circuit to drive an LED to indicate a Good Read status. When a good read occurs, the LED
pin produces a high level output for about 300ms, then the signal is back to a low level. This Decode LED
output is not strong enough to drive an LED, so an LED driver circuit is needed.
The following Decode LED driver circuit is provided for reference.
LED
R1 1K
R2
10K
VDD
2N3904
Q8
R3
1k
D3
LED
16