Overview
The BQ32002DR, produced by Texas Instruments, is a real-time clock (RTC) device designed as a compatible replacement for industry-standard real-time clocks. It features an automatic backup supply, which can be implemented using a capacitor or a non-rechargeable battery. This device is particularly useful in applications where continuous timekeeping is essential, even during power outages. The BQ32002DR supports an I2C interface with a serial clock frequency up to 400 kHz and includes integrated oscillator-fail detection and automatic leap-year compensation.
Key Specifications
| Parameter | Min | Max | Unit | |
|---|---|---|---|---|
| VCC Supply Voltage | 3.0 | 3.3 | 3.6 | V |
| VBACK Backup Supply Voltage | 1.4 | 3.6 | V | |
| ICC VCC Supply Current | 65 | 200 | μA | |
| IBACK Backup Supply Current | 2.4 | 3.9 | μA | |
| Operating Temperature | -40 | 85 | °C | |
| I2C Clock Frequency | 0 | 100 | 400 | kHz |
| Crystal Frequency | 32.768 | kHz | ||
| Package Type | 8-SOIC (4.90 mm × 3.91 mm) |
Key Features
- Automatic Backup Supply: The device can switch to a backup power supply using a capacitor or non-rechargeable battery when the main power supply voltage drops below a certain threshold.
- I2C Interface: Supports serial clock frequencies up to 400 kHz.
- Integrated Oscillator-Fail Detection: Detects failures in the oscillator and provides a flag in the device registers.
- Programmable Calibration Adjustment: Allows for calibration adjustments from –63 ppm to +126 ppm.
- Automatic Leap-Year Compensation: Automatically adjusts for leap years.
- IRQ Functionality: The IRQ pin can be configured as a general-purpose output or a frequency test output.
- Timekeeping Registers: Includes registers for hours, minutes, seconds, day of the week, date, and year, all updated synchronously to prevent timekeeping glitches.
Applications
The BQ32002DR is suitable for various applications in general consumer electronics where accurate and continuous timekeeping is crucial. These include:
- Smart home devices
- Automotive systems
- Industrial control systems
- Medical devices
- Consumer electronics such as clocks, timers, and calendar functions in appliances.
Q & A
- What is the primary function of the BQ32002DR?
The BQ32002DR is a real-time clock (RTC) device designed to keep accurate time and date, even during power outages, using an automatic backup supply.
- What type of interface does the BQ32002DR use?
The BQ32002DR uses an I2C interface with a serial clock frequency up to 400 kHz.
- How does the automatic backup supply work?
The device switches to the backup power supply when the main power supply voltage drops below a certain threshold, using an internal reference voltage.
- What is the operating temperature range of the BQ32002DR?
The operating temperature range is from -40°C to +85°C.
- What is the purpose of the IRQ pin?
The IRQ pin can be configured as a general-purpose output or a frequency test output, and its function is configurable through the device registers.
- Does the BQ32002DR support leap-year compensation?
Yes, the BQ32002DR includes automatic leap-year compensation.
- What is the crystal frequency used by the BQ32002DR?
The device uses a 32.768 kHz crystal.
- What is the package type of the BQ32002DR?
The BQ32002DR comes in an 8-SOIC package with dimensions of 4.90 mm × 3.91 mm.
- How does the oscillator-fail detection work?
The device includes integrated oscillator-fail detection, which sets a flag in the device registers if the oscillator fails.
- Can the calibration of the BQ32002DR be adjusted?
Yes, the calibration can be adjusted from –63 ppm to +126 ppm.
