Cypress CY8C21434 Manual De Usuario

Document Number: 38-12025  Rev. *O

Page 30 of 45

AC External Clock Specifications
The following tables list the guaranteed maximum and minimum specifications for the voltage and temperature ranges: 4.75V to 5.25V

and -40°C 

≤ T

A

 

≤ 85°C, or 3.0V to 3.6V and -40°C ≤ T

A

 

≤ 85°C, respectively. Typical parameters apply to 5V, 3.3V, or 2.7V at 25°C

and are for design guidance only. 

All 

Functions

Maximum Block Clocking Frequency

12.7

MHz

2.4V < Vdd < 3.0V.

Timer

Capture Pulse Width

100

–

–

ns

Maximum Frequency, With or Without Capture

–

–

12.7

MHz

Counter

Enable Pulse Width

100

–

–

ns

Maximum Frequency, No Enable Input

–

–

12.7

MHz

Maximum Frequency, Enable Input

–

–

12.7

MHz

Dead Band Kill Pulse Width:

Asynchronous Restart Mode

20

–

–

ns

Synchronous Restart Mode

100

–

–

ns

Disable Mode

100

–

–

ns

Maximum Frequency

–

–

12.7

MHz

CRCPRS

(PRS 

Mode)

Maximum Input Clock Frequency

–

–

12.7

MHz

CRCPRS

(CRC 

Mode)

Maximum Input Clock Frequency

–

–

12.7

MHz

SPIM

Maximum Input Clock Frequency

–

–

6.35

MHz

Maximum data rate at 3.17 MHz 

due to 2 x over clocking.

SPIS

Maximum Input Clock Frequency

–

–

4.1

MHz

Width of SS_ Negated Between Transmissions

100

–

–

ns

Transmitter Maximum Input Clock Frequency

–

–

12.7

MHz

Maximum data rate at 1.59 MHz 

due to 8 x over clocking.

Receiver

Maximum Input Clock Frequency

–

–

12.7

MHz

Maximum data rate at 1.59 MHz 

due to 8 x over clocking.

F

OSCEXT

Frequency

0.093

–

24.6

MHz

–

High Period

20.6

–

5300

ns

–

Low Period

20.6

–

–

ns

–

Power Up IMO to Switch

150

–

–

μs

20. 100 ns minimum input pulse width is based on the input synchronizers running at 12 MHz (84 ns nominal period).