ST72321B STMICROELECTRONICS [STMicroelectronics], ST72321B Datasheet - Page 150

• Manufacturer Part Number: ST72321B
• Description: 64/44-pin 8-bit MCU with 32 to 60K Flash/ROM, ADC, five timers, SPI, SCI, I2C interface
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

CLOCK CHARACTERISTICS (Cont’d)
Note:
1. Data based on characterization results.
12.5.5 PLL Characteristics
Note:
1. Data characterized but not tested.
The user must take the PLL jitter into account in the application (for example in serial communication or
sampling of high frequency signals). The PLL jitter is a periodic effect, which is integrated over several
CPU cycles. Therefore the longer the period of the application signal, the less it will be impacted by the
PLL jitter.
Figure 77
cies of less than 125KHz, the jitter is negligible.
Figure 77. Integrated PLL Jitter vs signal frequency
Note 1: Measurement conditions: f
150/187
f
∆ f
OSC
Symbol
CPU
+/-Jitter (%)
/ f
1.2
0.8
0.6
0.4
0.2
CPU
1
0
shows the PLL jitter integrated on application signals in the range 125kHz to 4MHz. At frequen-
4 MHz
PLL input frequency range
Instantaneous PLL jitter
2 MHz
Parameter
Application Frequency
1 MHz 500 kHz 250 kHz 125 kHz
1)
CPU
= 8MHz.
FLASH typ
ROM max
ROM typ
f
OSC
= 4 MHz.
Conditions
1
Min
2
Typ
0.7
Max
4
2
MHz
Unit
%