RV-3028-C7
Epson alternative: RX8111CE
You want to replace the RV-3028-C7 from Micro Crystal — as a second source, because of availability, or because a new design is coming up. Here the type is set against the closest Epson type feature by feature, with the points that speak for and against the change.
Also listed as RV-3028-C8.
Features of the RV-3028-C7: backup switch and trickle charger, 32-bit UNIX time counter, event input, 2 B RAM / 43 B EEPROM.
RV-3028-C7 versus RX8111CE
| RV-3028-C7 — Micro Crystal | RX8111CE — Epson | |
|---|---|---|
| Manufacturer | Micro Crystal | Epson (Seiko Epson) |
| Status | Active series type | Active series type |
| Interface | I²C | I²C |
| Crystal integrated | yes | yes, factory calibrated |
| Standby current | 45 nA (C7) bzw. 70 nA (C8) at 3 V | 100 nA typ. · 450 nA max. |
| Accuracy | ±1 ppm at +25 °C — factory calibrated, NOT temperature compensated | ±11.5 ppm at +25 °C (not compensated) |
| Temperature compensation | no | no |
| Supply | 1.1 – 5.5 V | 1.6–5.5 V |
| Max. temperature | +85 °C | −40 … +105 °C |
| Package | C7 · 3.2 × 1.5 × 0.8 mm · C8 · 2.0 × 1.2 × 0.7 mm | CE · 3.2 × 2.5 × 1.0 mm |
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
- Very low standby current of 45 nA
- At 2.4 mm² the C8 package is smaller than anything Epson has in the RTC programme
- 32-bit UNIX time counter directly in the device
The difference
- The ±1 ppm applies ONLY at +25 °C. The device is not temperature compensated — at 0 °C or +60 °C the built-in crystal follows the usual parabola and the deviation is orders of magnitude larger
- If you need accuracy over temperature, compare against the RX8901CE instead (DTCXO, ±3.0 ppm across the whole range)
- AEC-Q100 only from Epson
Frequently asked questions
What is the Epson alternative to the RV-3028-C7?
The closest match is the RX8111CE, with the RX4111CE as a second option. It is not a drop-in replacement: package, pinout and register map differ, so layout and firmware have to be adapted. What you get in return is set out in the comparison on this page.
Who supplies an alternative to the RV-3028-C7 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 RV-3028-C7.
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.