Datasheet

CY8C21x34B
Document Number: 001-67345 Rev. *E Page 30 of 49
AC External Clock Specifications
The following tables list the guaranteed maximum and minimum specifications for the voltage and temperature ranges: 4.75 V to
5.25 V and –40 °C  T
A
 85 °C, or 3.0 V to 3.6 V and –40 °C  T
A
 85 °C, respectively. Typical parameters are measured at 5 V,
3.3 V, or 2.7 V at 25 °C and are for design guidance only.
Table 27. 2.7-V AC Digital Block Specifications
Function Description Min Typ Max Units Notes
All
functions
Block input clock frequency – – 12.7 MHz 2.4 V < V
DD
< 3.0 V
Timer Capture pulse width 100
[25]
– – ns
Input clock frequency, with or without capture – – 12.7 MHz
Counter Enable input pulse width 100 – – ns
Input clock frequency, no enable input – – 12.7 MHz
Input clock 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
Input clock frequency – – 12.7 MHz
CRCPRS
(PRS Mode)
Input clock frequency – – 12.7 MHz
CRCPRS
(CRC Mode)
Input clock frequency – – 12.7 MHz
SPIM Input clock frequency – – 6.35 MHz The SPI serial clock (SCLK)
frequency is equal to the input
clock frequency divided by 2.
SPIS Input clock (SCLK) frequency – – 4.1 MHz
Width of SS_ Negated between transmissions 100 – – ns
Transmitter Input clock frequency – – 12.7 MHz The baud rate is equal to the input
clock frequency divided by 8.
Receiver Input clock frequency – – 12.7 MHz The baud rate is equal to the input
clock frequency divided by 8.
Table 28. 5-V AC External Clock Specifications
Symbol Description Min Typ Max Units Notes
F
OSCEXT
Frequency 0.093 –24.6MHz
– High period 20.6
– 5300 ns
– Low period 20.6
– –ns
– Power-up IMO to switch 150
– –µs
Note
25. 100 ns minimum input pulse width is based on the input synchronizers running at 12 MHz (84 ns nominal period).