MAX31328
Epson alternative: RX8901CE
The MAX31328 is Analog Devices' modern answer to the DS3231 — same idea, much smaller, much less current. It is the tightest competitor Epson faces here, and the comparison stays close. Which way it falls depends on current, area and temperature.
Both types carry a temperature-compensated oscillator with the crystal inside the package, so neither needs an external 32.768 kHz crystal.
MAX31328 versus RX8901CE
| MAX31328 — Analog Devices | RX8901CE — Epson | |
|---|---|---|
| Manufacturer | Analog Devices (formerly Maxim) | Epson (Seiko Epson) |
| Status | Active series type | Active series type |
| Interface | I²C (400 kHz) | I²C (400 kHz) |
| Crystal integrated | yes — TCXO with the crystal in the package | yes — DTCXO, factory calibrated |
| Accuracy | ±3.5 ppm from −40 to +85 °C | ±3.0 ppm across −40 to +85 °C (DTCXO) |
| Timekeeping current | 660 nA typ. at 3 V · 3.0 µA max. | 240 nA typ. · 1.5 µA max. |
| Supply | 2.3 – 5.5 V (VCC and VBAT) | 1.6 – 5.5 V · clock down to 1.1 V |
| Max. temperature | +85 °C | −40 … +105 °C |
| Package | 10-pin LGA, 5 × 5 mm · 25 mm² footprint | CE 3.2 × 2.5 × 1.0 mm · 8.0 mm² footprint |
| Extras | two alarms, temperature sensor, square-wave output | 32 timestamps (FIFO or 3 channels), 256 byte SRAM, self-monitoring |
What speaks for and against the change
We sell Epson — and we still say where the competitor is better. You would notice it at the first datasheet comparison anyway.
Honestly
- A genuinely modern part — far closer to Epson than the old DS3231 on both current and size
- It carries a temperature sensor readable over I²C, which Epson does not offer
- Register-compatible enough with the DS3231 family that migration inside Analog Devices is cheap
The difference
- Current: 240 nA typical against 660 nA, and 1.5 µA against 3.0 µA in the worst case
- Board area: 8.0 mm² against 25 mm² — about a third
- Temperature: +105 °C against +85 °C, which is what decides it for engine bays, enclosures and anything near a power stage
- Accuracy: ±3.0 ppm against ±3.5 ppm across the same range
- The clock keeps running down to 1.1 V, against 2.3 V — that is a longer usable backup life out of the same cell
Frequently asked questions
What is the Epson alternative to the MAX31328?
The RX8901CE is the closest match, with the RX8804CE where a DTCXO to +105 °C and an output port matter more than the timestamps. Neither is a drop-in: package, pinout and register map differ.
Is the MAX31328 better than the DS3231?
On the two figures that usually decide a design, yes. It draws 660 nA typical instead of 0.84 µA and comes in a 5 × 5 mm LGA instead of a 300-mil SO-16, at ±3.5 ppm across −40 to +85 °C. The DS3231 keeps its ±2 ppm advantage only inside the narrow 0 to +40 °C band.
Where does Epson win against the MAX31328?
On timekeeping current (240 nA against 660 nA), board area (8.0 mm² against 25 mm²), operating temperature (+105 °C against +85 °C) and clock supply voltage (down to 1.1 V against 2.3 V). On accuracy the two are close: ±3.0 against ±3.5 ppm.
Who supplies an alternative to the MAX31328 in Europe?
Timing Devices Europe in Ladenburg near Heidelberg, Germany stocks the complete Epson RTC programme in its own warehouse — physically on site, not at the manufacturer. Samples, comparison and series demand in one go, answered the same working day.
Samples and a comparison for the MAX31328.
Tell us which version you use today, together with quantity and date. We will put together the Epson equivalent with its datasheet and the migration effort — from our own warehouse in Ladenburg near Heidelberg, Germany.