UM1871 datasheet(21/64 Pages) STMICROELECTRONICS

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UM1871

Hardware layout and configuration

2.12

Analog input or output

The analog input or output connector CN21 can be connected to PA4 of STM32F446ZET6,

used as ADC or DAC analog IO.

Solder bridge SB91 must be opened and SB92, SB94, SB103 must be closed to connect

CN21 to PA4. CN21 is not connected by default to PA4, since SB94 is opened to support

camera interface by default.

In case CN21 is used as ADC, input low pass filter can be implemented by replacing SB92

and C86 with right value of resistor and capacitor, as requested by the end user’s

application. In case CN21 is used as DAC output, a low pass filter can be implemented by

replacing SB103 and C86 with the right value of resistor and capacitor, as requested by the

end user’s application.

2.13

CAN

STM32446E-EVAL evaluation board supports one channels of CAN2.0 A/B compliant CAN

bus communication based on 3.3 V CAN transceiver. The high-speed mode, standby mode

and slope control mode are available and can be selected by setting JP2.

SB19, marked in red in Figure 6, must be closed to connect CAN1_RX to PB8. CAN1_RX is

not connected by default to PB8, since SB19 is open to support camera interface by default.

Figure 6. PCB underside rework for CAN

Table 9. CAN related jumpers

Jumper

Description

JP2

CAN transceiver is working in standby mode when JP2 is set as shown to the right:

CAN transceiver is working in high-speed mode when JP2 is set as shown to the

right (default setting):

1 2 3

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