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Analog Devices DS1390U-3+ — Memory (DRAM / SRAM / Flash / EEPROM)

DS1390U-3+ Clock/Calendar RTC, SPI, Trickle-Charger, 10-uMAX

MPNDS1390U-3+
End of Life

Maxim Integrated DS1390U-3+, Clock/Calendar RTC, SPI, 10-uMAX, 2.7V–3.3V supply, -40°C to 85°C, trickle-charger, alarm, leap year, square wave output.

$5.46Ref. price · indicative, final on quote
Packaging10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

DS1390U-3+ specifications
ParameterValue
TypeClock/Calendar
MountingSurface Mount
Voltage2.7V ~ 3.3V
Voltage - supply, battery1.3V ~ 3.7V
Current - timekeeping125µA @ 2.7V ~ 3.3V
InterfaceSPI
Operating temperature-40°C ~ 85°C
PackageTube
FeaturesAlarm, Leap Year, Square Wave Output, Trickle-Charger
Date formatYY-MM-DD-dd
Time formatHH:MM:SS:hh (12/24 hr)
Case10-TFSOP, 10-MSOP (0.118\", 3.00mm Width)

Product details

SPI RTC with backup battery management

The Maxim Integrated DS1390U-3+ is a serial real-time clock (RTC) that keeps time as YY-MM-DD-dd and HH:MM:SS:hh in 12/24-hour format. Communication is over SPI. An integrated trickle-charger maintains a backup battery or supercap on the Vbat rail, so the clock holds through a main-supply dropout. The alarm output and square-wave generator can drive a host interrupt or toggle a logic line without polling. Supply range is 2.7 V to 3.3 V for the main rail; the battery backup input accepts 1.3 V to 3.7 V. Timekeeping current peaks at 125 µA over the full supply range, which keeps the load on the backup source low.

Housed in a 10-lead TFSOP/MSOP (3.00 mm body width). The supplier device package is 10-uMAX/uSOP.

Frequently asked questions

Does DS1390U-3+ have a trickle charger?

Yes, the DS1390U-3+ includes a trickle-charger for maintaining a backup battery or supercapacitor.

Is DS1390U-3+ RoHS compliant?

Yes, it is ROHS3 compliant.

Does DS1390U-3+ support 12/24 hour format?

Yes, the time format supports both 12-hour and 24-hour modes (HH:MM:SS:hh).

Where can I buy DS1390U-3+?

This part is sourced through independent distribution. Submit an RFQ for current availability and pricing; stock and lead time are confirmed at quote time.