DS1302N+

DS1302N+ is a low‑cost real‑time clock (RTC) in the DS1302 family. It keeps calendar time and offers a small amount of battery-backed RAM.
Key points:
- Timekeeping: seconds, minutes, hours, day, date, month, year with leap-year support; 12/24‑hour mode.
- Clock source: external 32.768 kHz crystal input.
- Interface: 3-wire serial (CE, CLK, IO) rather than standard SPI; simple read/write to time registers and 31 bytes of NV RAM.
- Power: operates from 2.0–5.5 V; battery backup via Vbat with an optional trickle-charge circuit to power a rechargeable battery or supercapacitor when main power is present.
- Memory: 31 bytes of battery-backed RAM for user data.
- Package: available in common IC packages (DIP8/SOP8).
- Usage: ideal for MCUs (Arduino, PIC, AVR) needing timekeeping and time-stamping with power loss protection.
Note: If you need higher accuracy, consider DS3231 (with built-in compensation). The DS1302N+ remains a popular, easy-to-use RTC for simple projects.

Key features of DS1302N+ RTC:
- Real-time clock with 32.768 kHz crystal input; keeps seconds/minutes/hours/date/month/day/year.
- 12/24-hour time mode; CH bit to stop the oscillator; day-of-week calendar.
- Battery-backed operation via VBAT with a built-in trickle-charge circuit to recharge a backup battery when VCC is present.
- 31 bytes of battery-backed SRAM (NVRAM) for user data.
- 3-wire serial interface (CE, CLK, I/O) for easy read/write of time, date, RAM.
- Programmable square-wave output on the I/O pin (frequency selectable).
- Wide supply voltage range: typically 2.0–5.5 V.
- Low power consumption suitable for battery-backed applications; operates over -40°C to +85°C.
- Available in common 8-pin packages (DIP/SOIC).
Note: DS1302N+ uses an external 32.768 kHz crystal and a simple 3-wire bus (not I2C/SPI).

DS1302N+ is an 8-pin device (DIP-8/SO-8).
Pin functions (typical):
- VCC: main power
- GND: ground
- VBAT: backup battery input (retains time when VCC is off)
- CE: chip enable (start/stop communication)
- SCLK: serial clock (clock line)
- IO: bidirectional data line
- X1, X2: trickle-charge inputs (for external resistor/diode network to charge backup battery)
Notes:
- Uses a 3-wire serial interface (CE, IO, SCLK)
- Maintains time with VBAT; supports optional trickle-charge circuit via X1/X2.

- Manufacturer: Dallas Semiconductor (the DS1302N+).
- What kind of company: A semiconductor company that designs and manufactures integrated circuits (RTCs, memory, etc.). Dallas Semiconductor is now part of Maxim Integrated, which is part of Analog Devices.

DS1302N+ is a real-time clock/calendar with battery backup and a small RAM. Common applications:
- Embedded systems needing accurate local time (MCUs, wearables)
- Data loggers and sensor networks for time-stamping measurements
- Alarm clocks, timers, and clock displays in consumer appliances
- Power-fail-safe timekeeping with coin-cell or backup capacitor
- Event logging and scheduling in industrial controllers
- Time-stamping for audit trails in small embedded systems
- Standalone timekeeping modules for evaluation boards or demos

DS1302N+ is an 8-pin device, available in DIP-8 (through-hole) and SO-8 (surface-mount) packages.