Real Time Clocks

What is a Real Time Clock?

A Real Time Clock (RTC) is a computer clock which is usually in the form of an integrated circuit. They have been designed to keep track of time, in real time - hence the product name. A Real Time Clock is usually an integral part of the computer motherboard. More often than not, an RTC will also include a calendar and an alarm

How do Real Time Clocks work?

The memory on the clocks system stores system descriptions and set up values such as "Current Time Value". The information that is held in the RTC is read with a microprocessor, commonly over a serial interface which facilitates the performance of the software functions that are time dependant.

Designed to run on ultra-low power consumption, RTCs often run on a lithium battery source but can also run on normal power. This power source allows them to continue running and generating real time when a system is down. The newer models of RTC use super-capacitors as a source of power that can be recharged and soldered to the board. Some Real Time Clocks feature synchronisation to an external signal, such as a compensated power line frequency. It allows the device to provide an accurate result without having an on-board temperature compensation scheme.

RTC Time Values

  • Year
  • Month
  • Date
  • Hours
  • Minutes
  • Seconds

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Viewing 421 - 429 of 429 products
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Description Price Functions Date Format Time Format User RAM Bus Type Mounting Type Package Type Pin Count Dimensions Length Width Height Maximum Operating Supply Voltage Maximum Operating Temperature
RS Stock No. 667-6221
Mfr. Part No.Q42724231000611
Calendar, Timer - - - Serial-I2C Surface Mount SOP 24 16.3 x 7.9 x 2.8mm 16.3mm 7.9mm 2.8mm 5.5 V +85 °C
RS Stock No. 904-7519
Mfr. Part No.X1B000301000212
Clock - SS:MM - Serial-I2C Surface Mount - 10 3.2 x 2.5 x 1mm 3.2mm 2.5mm 1mm 5.5 V +85 °C
RS Stock No. 189-8635
Mfr. Part No.DS1337S+
Each (In a Pack of 5)
Calendar DW:DM:M:Y HH:MM:SS - Serial-I2C Surface Mount SOIC 8 5 x 4 x 1.5mm 5mm 4mm 1.5mm 5.5 V +85 °C
RS Stock No. 190-5173
Mfr. Part No.DS1374U-18+
Each (In a Pack of 5)
Binary Counter, Real Time Clock, Trickle Charger - - - Serial-I2C Surface Mount μSOP 10 3.16 x 3.12 x 0.95mm 3.16mm 3.12mm 0.95mm 1.89 V +85 °C
RS Stock No. 192-1626
Mfr. Part No.DS1248Y-70+
SRAM with Phantom Clock YY:MM:DD HH:MM:SS:hh 128 x 8bit Serial Through Hole EDIP 32 44.2 x 18.8 x 10.92mm 44.2mm 18.8mm 10.92mm 5 V +70 °C
RS Stock No. 171-0195
Mfr. Part No.AB0805-T3
Each (On a Reel of 3000)
- - - - - Surface Mount 16-VFQFN - - - - - - 85 °C
RS Stock No. 732-7535
Mfr. Part No.DS2417P+
Battery Backup, Calendar, ROM Binary Binary - Serial Surface Mount TSOC 6 4 x 3.89 x 1.5mm 4mm 3.89mm 1.5mm 5.5 V +85 °C
RS Stock No. 190-5835
Mfr. Part No.DS1339C-33#T&R
Each (In a Pack of 2)
Alarm, Clock, Real Time Clock, Square Wave Output, Trickle Charger DM:M:DW:Y SS:MM:HH - Serial-I2C Surface Mount SO 16 10.5 x 7.6 x 2.35mm 10.5mm 7.6mm 2.35mm 5.5 V +85 °C
RS Stock No. 171-1646
Mfr. Part No.RV-4162-C7-TA-020
Each (On a Tape of 100)
Calendar DW:DM:M:Y HH:MM:SS - Serial-I2C Surface Mount SMD 8 3.2 x 1.5 x 0.8mm 3.2mm 1.5mm 0.8mm 4.4 V +85 °C