ST72324BK2 STMicroelectronics, ST72324BK2 Datasheet - Page 33

• Manufacturer Part Number: ST72324BK2
• Description: 5V RANGE 8-BIT MCU WITH 8 TO 32K FLASH/ROM, 10-BIT ADC, 4 TIMERS, SPI, SCI INTERFACE
• Manufacturer: STMicroelectronics

Specifications of ST72324BK2

• Hdflash Endurance: 1 kcycle at 55 °C, data retention 40 years at 85 °C
• Clock Sources: crystal/ceramic resonator oscillators, int. RC osc. and ext. clock input
• 4 Power Saving Modes: Slow, Wait, Active-halt, and Halt

ST72324Bxx
6.3.2
6.3.3
Crystal/ceramic oscillators
This family of oscillators has the advantage of producing a very accurate rate on the main
clock of the ST7. The selection within a list of four oscillators with different frequency ranges
has to be done by option byte in order to reduce consumption (refer to
179
resonator and the load capacitors have to be placed as close as possible to the oscillator
pins in order to minimize output distortion and start-up stabilization time. The loading
capacitance values must be adjusted according to the selected oscillator.
These oscillators are not stopped during the reset phase to avoid losing time in the oscillator
start-up phase.
Internal RC oscillator
This oscillator allows a low cost solution for the main clock of the ST7 using only an internal
resistor and capacitor. Internal RC oscillator mode has the drawback of a lower frequency
accuracy and should not be used in applications that require accurate timing.
In this mode, the two oscillator pins have to be tied to ground.
In order not to exceed the maximum operating frequency, the internal RC oscillator must not
be used with the PLL.
Table 9.
for more details on the frequency ranges). In this mode of the multi-oscillator, the
ST7 clock sources
C
Hardware configuration
L1
External
source
OSC1
OSC1
OSC1
capacitors
Load
ST7
ST7
ST7
Supply, reset and clock management
OSC2
OSC2
OSC2
C
L2
Section 14.1 on page
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