SH3000 SEMTECH [Semtech Corporation], SH3000 Datasheet - Page 12

• Manufacturer Part Number: SH3000
• Description: Low-Power Programmable Multifunction Support IC for Microcontrollers
• Manufacturer: SEMTECH [Semtech Corporation]

Periodic Interrupt / Wakeup Timer
Timer can be used to create very accurate recurring
interrupts for use by the host micro. With some
minimum software support from the host processor, it
can also be used to create alarms, with practically
unlimited duration.
be halted, consuming no energy. The interrupt wakes
up the processor, which can perform the requisite task
and go back to sleep, until the next periodic interrupt.
average power consumption.
minimum interval of 30.5 µs and the maximum interval of
36.4 hours, creates the Timer.
for the time interval is written into the 4-byte Time
Interval register. When the least significant byte (LSB) is
written, the whole value is moved to the Time Interval
latch, the counter is reset and starts to increment with
the 32 kHz clock.
interrupt is generated and the counter is reset and starts
the next timing cycle.
current value from the counter can be read at any time.
The whole 32-bit value is loaded into the 32-bit Current
Timer Value latch when the least significant byte is read.
This prevents errors stemming from the finite time
between the readings of individual bytes of the current
value.
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SYSTEM MANAGEMENT
Simple and versatile, the Periodic Interrupt / Wakeup
While the timer is running, the host processor may
This mode of operation can achieve extremely low
A 32-bit counter clocked by 32.768 kHz, producing a
After reset, the Timer is stopped until the new value
When the 32-bit comparator detects a match, an
Although the counter cannot be written to, the
12
Auxiliary functions
Scratchpad RAM and ID number
the SH3000. Immediately after reset, they are loaded
with the factory-programmed values in the OTP memory.
For a standard device these values are 0x00, 0x00,
0x00, 0x00. Unique serial numbers or other information
could be located there. Please contact the factory for
custom requirements.
Voltage Regulator
Pin V
voltage or a supply source for small loads (<2 mA). A
bypass capacitor may be necessary between this pin
and V
a low ripple reference is required.
Four (4) bytes of general-purpose RAM reside on
REG
SS
if the load generates large current transients or
can be used as a nominal 2.20 V reference
SH3000 MicroBuddy™
V1.15
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