Analog Input; Comparator - STMicroelectronics STM32L152D-EVAL User Manual

UM1521
2.16

Analog input

A 2-pin connector, CN8, is connected to PA4 of the STM32L152ZDT6 as an external analog
input or DAC output. A low pass filter can be implemented for a 2-pin connector by replacing
R43 and C35 with ADC input or replacing R36 and C35 with DAC output, with correct values
of resistor and capacitor as requested by end user's application.
There are also three analog signals available on the board:
1. 10 KOhm potentiometer RV3 connected to PF10.
2. 10 KOhm potentiometer RV3 connected to OpAmp2 PA6.
3. I measurement output signal connected to PF11 for MCU power consumption test.
DD
Table 17.
Jumper
10 KOhm potentiometer RV3 connected to OpAmp2 PA6 when JP12 is closed.
JP12
Default setting: Closed
JP7 Description of JP7 is in
2.17

Comparator

Three I/Os implement a comparator feature as shown in
● Comparator non-inverting input PB4; connected to LDR (R157).
● Comparator inverting input PB3; connected to potentiometer (RV3) used as variable
threshold input for comparison to luminosity measured on LDR.
● Comparator non-inverting input PB5; connected to potentiometer (RV3) used as analog
voltage input for comparison with internal voltage reference (for instance Band gap) in
order to test analog Wakeup feature of the MCU.
Figure 8.
www.BDTIC.com/ST
Analog input related jumpers
Section 2.7: Audio
STM32L152D-EVAL comparator features
Doc ID 022868 Rev 1
Hardware layout and configuration
Description
Figure 8:
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