9
Potentiometers
EVBlpc213x has two potentiometers, POT0 and POT1. The potentiometers can be used to simulate the
outputs of analog circuits. The voltage across POTx terminals can be adjusted in the 0...3.3V range.
10k
1
3
2
R20
ADJ1
GND
10k
1
3
2
R21
ADJ0
1
2
3
4
J13
+3.3V
Figure 8
Implementation of potentiometers.
Buzzer
The board has a built-in acoustic signaler, controlled by a logic low state through a transistor. The base of the
transistor is connected to connector J13 as SPK.
LS1
BUZZER
Q1
BC 857
C17
100n
GND
GND
1
2
3
4
J13
R6
10k
R23
10k
+3.3V
Figure 9
Implementation of the Buzzer.
RESET button
The EVBlpc213x board is equipped with an on-board resetting button; by pressing it we force a low state on
the RESET terminal of the module.
#RESET
SW6
RESET
GND
Figure 10
Implementation of the RESET push-button.
