Microcontrollers often require a precise power supply in order to operate properly and these devices come with additional monitoring circuits to check if the power supply operates within narrow safety margins, improving overall system reliability.
When voltage exceeds the safety margins, the microcontroller must be reset to prevent it from working improperly. The R5116 and R5117 both have a 500mA voltage regulator and supervisory circuits embedded in a single package which saves valuable circuit board space and additional wiring between the components, providing the designer a cost effective solution with minimal external components. The R5116 monitors the output voltage for both over- and under-voltage while the R5117 monitors both the input voltage and output voltage for under-voltage. The CMOS-based chips are robust enough to survive in harsh conditions; operating up to 42V and tolerating load dump surge peak voltages of 60V under 200ms. Minimum operating voltage starts at 3.5 V. The product will be available in a version intended for the consumer, industrial and automotive application market with customized operating temperature ranges up to -50 to 125°C, with an automotive version soon AEC-Q100 compliant. All settings for the output voltage and supervisory thresholds are internally fixed by laser trimming to a high accuracy level. Ripple rejection ratio is in the range of 70dB at 1kHz. The R5116 and R5117 draw 25 and 35μA in On-mode and 1.5 and 10μA in Off-mode, respectively. Thermal protection is incorporated and will turn off the regulator when an over-temperature of 175°C is detected and will resume to normal operation again as it reaches 145°C.
Ricoh Electronic Devices - www.e-devices.ricoh.co.jp