S-35392A-I8T1U

Real Time Clock Overview

The ABLIC S-35392A is a CMOS 2-wire real-time clock IC designed for low current consumption across a wide operating voltage range of 1.3 V to 5.5 V. It features a typical timekeeping current of 0.45 µA at 3.0 V and 25°C, extending battery life in backup systems. The device includes an I²C interface, auto-calendar functionality up to the year 2099 with leap year calculation, and a built-in clock correction register to compensate for crystal frequency deviations. It provides free user registers for data backup during power loss and supports alarm interrupts.

Real Time Clock Feature Summary

• Low current consumption: 0.45 µA typ. (VDD = 3.0 V, Ta = +25°C)
• Wide operating voltage range: 1.3 V to 5.5 V
• Built-in clock correction function and temperature sensor compatibility
• Auto-calendar up to 2099 with automatic leap year calculation
• Free user registers for backup memory during main power failure

Real Time Clock Applications

• Mobile game devices
• Digital still cameras
• Electronic power meters
• DVD recorders
• TV and VCR units

Real Time Clock Procurement Notes

Verify the package type SNT-8A and tape packing specification corresponding to the I8T1 suffix. Confirm environmental compliance as lead-free (Sn 100%) and halogen-free. Ensure the supply voltage meets the minimum oscillation start requirement of 1.1 V within 10 seconds. Check that the external quartz crystal matches the recommended CL value of 6 pF.

Real Time Clock Selection Notes

Select this component for applications requiring precise timekeeping with minimal power drain from backup batteries. The built-in clock correction feature allows compensation for crystal aging and temperature variations without external components. Ensure the system design accommodates the open-drain outputs on SDA, 32KO, and INT2 pins by providing appropriate pull-up resistors to VDD.

Real Time Clock Part Context

The S-35392A belongs to the S-35392 series of 2-wire real-time clocks manufactured by ABLIC Inc. It utilizes the SNT-8A surface-mount package. The model suffix I8T1 indicates the specific package variant and tape-and-reel packing configuration suitable for automated assembly processes.

Real Time Clock Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Verify pin compatibility and I²C address if considering alternative RTCs from other manufacturers.

Real Time Clock FAQ

How does the S-35392A handle power-on detection?

The device includes a power-on detection circuit that sets the POC flag (B0 in Status Register 1) to '1' when power is applied. Users must initialize the internal circuit by writing '1' to the RESET bit in Status Register 1 upon detecting this flag.

What is the function of the BLD flag?

The BLD (Battery Low Detection) flag in Status Register 1 is set to '1' when the power supply voltage drops to or below the detection voltage (VDET). This flag remains set even if voltage recovers, indicating that the internal circuit may be in an indefinite status and requires re-initialization.

Can the S-35392A operate in both 12-hour and 24-hour modes?

Yes, the mode is selected via the 24/12 bit (B6) in Status Register 1. Setting it to '0' enables 12-hour mode, while '1' enables 24-hour mode. The hour data format in the real-time data register adjusts accordingly.