MB96F348CWCPMC-GSE2 datasheet(57/109 Pages) CYPRESS

57 / 109 page

MB96340 Series

Document Number: 002-04579 Rev. *A

Page 57 of 109

13.7

Crystal oscillator and ceramic resonator circuit

Noise at X0, X1 pins or X0A, X1A pins might cause abnormal operation. It is required to provide bypass capacitors with shortest

possible distance to X0, X1 pins and X0A, X1A pins, crystal oscillator (or ceramic resonator) and ground lines, and, to the utmost

effort, that the lines of oscillation circuit do not cross the lines of other circuits.

It is highly recommended to provide a printed circuit board art work surrounding X0, X1 pins and X0A, X1A pins with a ground area

for stabilizing the operation.

It is highly recommended to evaluate the quartz/MCU or resonator/MCU system at the quartz or resonator manufacturer, especially

when using low-Q resonators at higher frequencies.

13.8

Turn on sequence of power supply to A/D converter and analog inputs

It is required to turn the A/D converter power supply (AVCC, AVRH, AVRL) and analog inputs (ANn) on after turning the digital power

supply (VCC) on.

It is also required to turn the digital power off after turning the A/D converter supply and analog inputs off. In this case, the voltage

must not exceed AVRH or AVCC (turning the analog and digital power supplies simultaneously on or off is acceptable).

13.9

Pin handling when not using the A/D converter

It is required to connect the unused pins of the A/D converter as AVCC = VCC, AVSS = AVRH = AVRL = VSS.

13.10 Notes on Power-on

To prevent malfunction of the internal voltage regulator, supply voltage profile while turning the power supply on should be slower than

s from 0.2 V to 2.7 V.

13.11 Stabilization of power supply voltage

If the power supply voltage varies acutely even within the operation safety range of the Vcc power supply voltage, a malfunction may

occur. The Vcc power supply voltage must therefore be stabilized. As stabilization guidelines, the power supply voltage must be

stabilized in such a way that Vcc ripple fluctuations (peak to peak value) in the commercial frequencies (50 to 60 Hz) fall within 10%

of the standard Vcc power supply voltage and the transient fluctuation rate becomes 0.1V/

s or less in instantaneous fluctuation for

power supply switching.

13.12 Serial communication

There is a possibility to receive wrong data due to noise or other causes on the serial communication.Therefore, design a printed

circuit board so as to avoid noise.Consider receiving of wrong data when designing the system. For example apply a checksum and

retransmit the data if an error occurs.

13.13 Handling of Data Flash

The Data Flash requires different and additional control signals for parallel programming. Please check with your programming

equipment maker for support of this interface.

MB96F348CWCPMC-GSE2 Datasheet(PDF) 57 Page - Cypress Semiconductor