Microchip Technology has expanded its stand-alone real-time clock/calendars (RTCCs) with the MCP7940N RTCC, which offers battery switchover and timestamp for accurate timekeeping, digital trimming for time-of-day calibration and 64 bytes of SRAM. Starting at $0.57 each in 10,000-unit quantities, it offers a lower-cost alternative to the existing MCP7941X devices, which feature 1Kbit of EEPROM memory and a 64-bit reprogrammable unique ID.
Example applications include smart-energy devices such as thermostats, power meters, and commercial refrigeration; home-appliances such as stoves, dishwashers, and microwave ovens; automotiveapplications such as dashboard controls and car radios; and consumer-electronic markets such as cameras, notebook PCs, office equipment, irrigation controls, and video systems.
With its on-chip battery-switchover circuit and power-fail timestamp, the MCP7940N RTCC provides a real-time clock with a power-fail monitor and back-up power to maintain time and alarm settings when the main power is turned off, helping to address system health, safety, and security concerns in applications involving the storage of perishable goods, or the monitoring of access to secure rooms. The digital-trimming feature can support software temperature compensation, which lowers costs in comparison to devices where temperature compensation takes place in hardware. The device’s 64 bytes of SRAM can temporarily store information, which further reduces overall system cost.
Developers can begin designing today with Microchip’s MCP7941x RTCC PICtail Plus Daughter Board (part #AC164140, $45), which can also be used with Microchip’s existing MCP794XX family of devices. This daughter board works with Microchip’s Explorer 16 Development Board (part # DM240001, $129.99), PIC18 Explorer Board (part #DM183032, $99.99), PICkit Serial Analyzer (part #DV164122, $49.99), and XLP 16-bit Development Board (part #DM240311, $59.99), all of which are available now.
Packaging, Pricing and Availability
The MCP7940N RTCC is available in SOIC for $0.57 each, MSOP for $0.60 each, TSSOP for $0.60 each and 2mm x 3mm TDFN packages for $0.64 each, in 10,000-unit quantities. Samples are available at www.microchip.com/get/GQQQ. For additional information, contact any Microchip sales representative or authorized worldwide distributor, or visit Microchip’s Web site at www.microchip.com/get/4F2S.