The smôl RTC is a miniature real-time clock board based on the RV-8803-C7, designed for the smôl ecosystem of stackable low-power boards. The RV-8803 features factory-calibrated temperature compensation for extremely precise timekeeping, with accuracy of ±1.5 ppm from 0 °C to 50 °C.

smôl boards stack using 16-way 0.5 mm pitch flexible printed circuits (FPCs), creating compact, low-power systems ideal for wildlife tracking, environmental monitoring, and other long-term deployments. The RTC includes a rechargeable backup battery to maintain time when the main system is powered down.

Key Features

• Factory-Calibrated Temperature Compensation – ±1.5 ppm (0 °C to 50 °C), ±3.0 ppm (−40 °C to 85 °C), ±7.0 ppm (85 °C to 105 °C)
• Ultra-Low Power – 240 nA at 3.3 V, ideal for battery-powered applications
• Wide Voltage Range – 1.5 V to 5.5 V operating voltage
• Rechargeable Backup Battery – Maintains time when main power is removed
• Alarm and Timer Interrupts – Configurable alarms for weekday/date, hour, and minute; periodic countdown and time-update interrupts
• External Event Input – EVI pin with interrupt and timestamp function, accessible via breakout pad
• Configurable INT Jumpers – Interrupt pin can be connected to the smôl bus GPIO if required
• I2C Interface – Address 0x32

Specifications

• RTC Chip – RV-8803-C7
• Operating Temperature – −40 °C to 105 °C
• Dimensions – 40.6 × 10.7 × 3.2 mm
• Weight – 1.1 g
• PCB Thickness – 0.8 mm

Ideal For

• Wildlife tracking and environmental monitoring
• Low-power data logging with accurate timestamps
• Field applications in harsh temperature environments
• Compact smôl-based sensor systems

Resources

• smôl Hookup Guide
• Datasheet (RV-8803-C7)
• Application Manual (RV-8803-C7)
• Schematic
• Arduino Library
• Hardware Design Files