ST72344S4 STMicroelectronics, ST72344S4 Datasheet - Page 43

• Manufacturer Part Number: ST72344S4
• Description: 8-bit MCU
• Manufacturer: STMicroelectronics

Specifications of ST72344S4

• Up To 16 Kbytes Program Memory: single voltage extended Flash (XFlash) with readout and write protection, in-circuit and inapplication programming (ICP and IAP). 10K write/erase cycles guaranteed, data retention
• 256 Bytes Data Eeprom With Readout Protection. 300k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55 °C.
• Clock Sources: crystal/ceramic resonator oscillators, high-accuracy internal RC oscillator or external clock
• 5 Power-saving Modes: Slow, Wait, Halt, Auto-wakeup from Halt and Active-halt
• 16-bit Timer A With: 1 input capture, 1 output compares, external clock input, PWM and pulse generator modes
• 16-bit Timer B With: 2 input captures, 2 output compares, PWM and pulse generator modes

ST72344xx ST72345xx
7.3
Caution:
7.3.1
7.3.2
Multioscillator (MO)
The main clock of the ST7 can be generated by three different source types coming from the
multioscillator block:
●
●
●
Each oscillator is optimized for a given frequency range in terms of consumption and is
selectable through the option byte. The associated hardware configurations are shown in
Table
The OSC1 and/or OSC2 pins must not be left unconnected. For the purposes of Failure
Mode and Effect Analysis, it should be noted that if the OSC1 and/or OSC2 pins are left
unconnected, the ST7 main oscillator may start and, in this configuration, could generate an
f
unsafe/undefined state. The product behavior must therefore be considered undefined when
the OSC pins are left unconnected.
External clock source
In this external clock mode, a clock signal (square, sinus or triangle) with ~50% duty cycle
has to drive the OSC1 pin while the OSC2 pin is tied to ground.
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 4 oscillators with different frequency ranges
has to be done by option byte in order to reduce consumption (refer to
232
resonator and the load capacitors have to be placed as close as possible to the oscillator
pins in order to minimize output distortion and startup 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
startup phase.
OSC
for more details on the frequency ranges). In this mode of the multi-oscillator, the
an external source
4 crystal or ceramic resonator oscillators
an internal high-accuracy RC oscillator
clock frequency in excess of the allowed maximum (>16 MHz.), putting the ST7 in an
8. Refer to the electrical characteristics section for more details.
Doc ID 12321 Rev 5
Supply, reset and clock management
Section 15.1 on page
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