ST72F324K6TCRS View Datasheet(PDF) - STMicroelectronics

Part Name

Description

MFG CO.

ST72F324K6TCRS

8-bit MCU for automotive, 3.8 to 5.5V operating range with 8 to 32 Kbyte Flash, 10-bit ADC, 4 timers, SPI, SCI

STMicroelectronics 

ST72324xx-Auto

Electrical characteristics

12.13.2 General PCB design guidelines

To obtain best results, some general design and layout rules should be followed when

designing the application PCB to shield the noise-sensitive, analog physical interface from

noise-generating CMOS logic signals.

● Use separate digital and analog planes. The analog ground plane should be connected

to the digital ground plane via a single point on the PCB.

● Filter power to the analog power planes. It is recommended to connect capacitors, with

good high frequency characteristics, between the power and ground lines, placing

0.1µF and optionally, if needed, 10pF capacitors as close as possible to the ST7 power

supply pins and a 1 to 10µF capacitor close to the power source (see Figure 88).

● The analog and digital power supplies should be connected in a star network. Do not

use a resistor, as VAREF is used as a reference voltage by the A/D converter and any

) resistance would cause a voltage drop and a loss of accuracy.

t(s ● Properly place components and route the signal traces on the PCB to shield the analog

c inputs. Analog signals paths should run over the analog ground plane and be as short

u as possible. Isolate analog signals from digital signals that may switch while the analog

d inputs are being sampled by the A/D converter. Do not toggle digital outputs on the

ro same I/O port as the A/D input being converted.

te P Figure 88. Power supply filtering

ole 1 to 10µF

- Obs VDD

ST7

digital noise

+ filtering

t(s) Power

supply

Obsolete Producsource

External

noise

filtering

0.1µF

ST72XXX

VSS

VDD

0.1µF

VAREF

VSSA

Doc ID 13841 Rev 1

173/193

Share Link: