Features
- Real-Time Clock (RTC) counts seconds, minutes, hours, day, date, month, and year with leap-year compensation valid up to 2100
- Packaged in 8-pin MSOP, 8-pin SOIC, or 16-pin SOIC (surface-mount package with an integrated crystal)
- Fast mode I2C Serial interface
- Two time-of-day alarms
- Programmable square-wave output
- Oscillator stop flag
- Automatic power-fail detect and switch circuitry
- Trickle-charge capability
- Industrial temperature range (-40 to +85°C)
- Underwriters Laboratory (UL) recognized
Description
The 1339 serial real-time clock (RTC) is a low-power clock/date device with two programmable time-of-day alarms and a programmable square-wave output. Address and data are transferred serially through an I2C bus. The clock/date provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. The 1339 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time, date, and alarm operation.
Parameters
| Attributes | Value |
|---|---|
| Output Freq Range (MHz) | 1.0E-6 - 1.0E-6, 0.004096 - 0.004096, 0.008192 - 0.008192, 0.032768 - 0.032768 |
| Power Consumption Typ (mW) | 10 |
| Output Type | LVCMOS |
| Package Area (mm²) | 9, 19.1 |
| Interface | I2C |
| Alarms (#) | 2 |
| Supply Voltage Vcc (Min) (V) | 2 |
| Battery Backup | No |
| Battery Seal | No |
| CPU Supervisory Function POR | No |
| Crystal Frequency Trimming | No |
| Frequency Out Pin | No |
| Battery Current (nA) | 300 |
| Time Keeping Current (µA) | 1.4 |
| Selectable Frequency Output | 1 |
| Accuracy | ±20 ppm |
| Inputs (#) | 1 |
| Input Freq (MHz) | 0.032768 - 0.032768 |
| Input Type | Crystal |
| Output Banks (#) | 1 |
| Core Voltage (V) | 2.5V, 3.3V, 5V, 5.5V |
| Output Voltage (V) | 2.5V, 3.3V, 5V, 5.5V |
| Product Category | Real-Time Clocks, Real-Time Clocks |
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