ST62E32BF1 STMicroelectronics, ST62E32BF1 Datasheet - Page 18

• Manufacturer Part Number: ST62E32BF1
• Description: 8-bit Microcontrollers - MCU UV EPROM 8K SPI/UART
• Manufacturer: STMicroelectronics

Specifications of ST62E32BF1

• Product Category: 8-bit Microcontrollers - MCU
• Core: ST6
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 8 MHz
• Program Memory Size: 7948 B
• Data Ram Size: 192 B
• On-chip Adc: Yes
• Package / Case: SDIP-42
• Mounting Style: Through Hole
• A/d Bit Size: 8 bit
• A/d Channels Available: 21
• Data Rom Size: 128 B
• Interface Type: SPI, UART
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Number Of Programmable I/os: 30
• Number Of Timers: 1 x 8 bit
• Program Memory Type: EPROM
• Factory Pack Quantity: 13
• Supply Voltage - Max: 5 V
• Supply Voltage - Min: 4.5 V

ST62T32B ST62E32B
3 CLOCKS, RESET, INTERRUPTS AND POWER SAVING MODES
3.1 CLOCK SYSTEM
The MCU features a Main Oscillator which can be
driven by an external clock, or used in conjunction
with an AT-cut parallel resonant crystal or a suita-
ble ceramic resonator. In addition, a Low Frequen-
cy Auxiliary Oscillator (LFAO) can be switched in
for security reasons, to reduce power consump-
tion, or to offer the benefits of a back-up clock sys-
tem.
The Oscillator Safeguard (OSG) option filters
spikes from the oscillator lines, provides access to
the LFAO to provide a backup oscillator in the
event of main oscillator failure and also automati-
cally limits the internal clock frequency (f
function of V
ation. These functions are illustrated in
Figure
figurations using an external crystal or ceramic res-
onator, an external clock input or the lowest cost so-
lution using only the LFAO. C
a capacitance in the range 12 to 22 pF for an oscillator
frequency in the 4-8 MHz range.
The internal MCU clock frequency (f
by 12 to drive the Timer and the Watchdog timer,
and by 13 to drive the CPU core, while the A/D
converter is driven by f
12 as may be seen in
With an 8 MHz oscillator frequency, the fastest ma-
chine cycle is therefore 1.625µs.
A machine cycle is the smallest unit of time needed
to execute any operation (for instance, to increment
the Program Counter). An instruction may require
two, four, or five machine cycles for execution.
3.1.1 Main Oscillator
The main oscillator can be turned off (when the
OSG ENABLED option is selected) by setting the
OSCOFF bit of the OSCR Control Register. The
Low Frequency Auxiliary Oscillator is automatical-
ly started.
18/83
Figure 9
11,
illustrates various possible oscillator con-
Figure 12
DD
, in order to guarantee correct oper-
and
INT
Figure
divided either by 6 or by
Figure
L1
12.
an C
13.
L2
INT
should have
) is divided
Figure
INT
) as a
10,
Figure 9. Oscillator Configurations
C
CRYSTAL/RESONATOR CLOCK
L1n
INTEGRATED CLOCK
OSG ENABLED option
OSC
OSC
EXTERNAL CLOCK
OSC
in
in
in
ST6xxx
ST6xxx
ST6xxx
OSC
OSC
OSC
NC
NC
out
out
out
C
L2
VA0015A
VA0016