Low energy consumption microcontrollersHitachi proposes a family of low energy consumption devices, offering a 16MHz 8/16-bit CPU and a reduced operation voltage (from 1,8 to 5,5 V).
These features make the H8/3847R series suitable for low consumption energy applications such as: domestic and industrial electric counters, and battery applications such as data loggers and sensors.
H8/3847R can make a 16 bit addition in just 250 nanoseconds and a 8 bit multiplication in 1,75 microseconds.
The device has an LCD controller that can display up to 1-60 segments and an event counter for asynchronous events designed to count eternal impulses. The H8/3847R device’s 32 kHz sub-oscillator enables a wide range of low consumption operation modes, such as the standby module and the watch mode, whereas the oscillator can be used to supply the timebase for a real time clock.
This range of modes enables the device to reduce consumption of energy during operation to the minimum. The stabilization time of the main oscillator is 1000 times inferior to that of normal devices (normally 20 microseconds against the typical 20 milliseconds). This permits the reduction of the total energy consumption of metering or data logging systems, since the device activates its main oscillator only to process an external event and then it goes back, immediately, to low-consumption mode.
This causes an increate of battery duration. The H8/3847R has 60 kbyte of ROM or OTP memory, up to 2 kbytes of SRAM, three 8 bit timers, one 16 bit timer and a watchdog timer, two U5ART5, 12 10-bit A/D converter channels, a serial synchronous interface and 84 pin I/O.
