PT7C4337ZEEX

Real Time Clock Overview

The PT7C4337ZEEX is a Real-Time Clock (RTC) module manufactured by Diodes Incorporated, housed in an 8-pin WDFN package. It operates via a 2-wire I2C bus interface and supports both 12-hour and 24-hour time formats with date tracking for years, months, days, and weekdays. The device utilizes an external 32.768kHz crystal connected to X1 and X2 pins. Electrical specifications include a supply voltage range of 1.8V to 5.5V for active operation and 1.2V to 1.8V for timekeeping. It features two programmable alarms, a programmable square wave output, and oscillator fail detection capabilities.

Real Time Clock Feature Summary

• I2C Bus Interface: Supports standard communication up to 400 kHz with open-drain SDA and SCL pins requiring external pull-up resistors.
• Dual Alarm System: Includes Alarm 1 (seconds through day/date) and Alarm 2 (minutes through day/date) with configurable mask bits for interrupt generation on INTA or SQW/INTB pins.
• Programmable Square Wave Output: Generates frequencies of 1 Hz, 4.096 kHz, 8.192 kHz, or 32.768 kHz via the SQW/INTB pin.
• Low Power Operation: Timekeeping current is typically 450 nA at 1.8V; data retention current is under 160 nA when the oscillator is disabled.

Real Time Clock Applications

• Embedded systems requiring precise time and calendar tracking.
• Battery-powered devices utilizing low standby current modes.
• Industrial equipment operating within -40°C to +85°C temperature ranges.
• Consumer electronics needing alarm functionality and periodic interrupts.

Real Time Clock Procurement Notes

Verify that the ordering suffix 'ZE' corresponds to the 8-pin WDFN package as specified in the manufacturer's documentation. Confirm RoHS compliance status and lead-free manufacturing definitions directly from the supplier. Ensure external components match the recommended crystal load capacitance values for accurate frequency performance.

Real Time Clock Selection Notes

Select this component if an 8-pin surface-mount package is required for space-constrained designs. Verify that the system voltage remains within the 1.8V to 5.5V range for full functionality. Ensure the microcontroller supports the I2C protocol and can handle the open-drain requirements for SDA and SCL lines. Check if the specific WDFN footprint matches the PCB layout guidelines provided in the datasheet.

Real Time Clock Part Context

The PT7C4337ZEEX belongs to the PT7C4337 family of real-time clock modules. Other variants in this series include the W (SOIC), U (MSOP), and L (TSSOP) packages. All variants share identical electrical characteristics and functional registers, differing only in physical packaging dimensions and mechanical specifications.

Real Time Clock Replacement Considerations

Direct replacements must maintain the 8-pin WDFN form factor and I2C compatibility. Verify register-level compatibility if substituting with other RTC ICs. Ensure the alternative part supports the same voltage ranges and alarm configurations to avoid firmware modifications.

Real Time Clock FAQ

How is the oscillator stop flag handled?

The OSF bit in the Status Register (Address 0Fh) indicates an oscillator failure. This flag is set when the oscillator stops and can be cleared by writing a logic 0 to the bit.

What are the supported square wave frequencies?

The SQW/INTB pin can output square waves at 1 Hz, 4.096 kHz, 8.192 kHz, or 32.768 kHz, selected via the RS2 and RS1 bits in the Control Register.

Does the device support century tracking?

No, the PT7C4337 does not support a century bit. It tracks years in a 00-99 format.