Real Time Clocks
Explore Real Time Clocks parts from multiple manufacturers, with model information, availability, datasheets and technical specifications for engineering and purchasing.
For parts that are not shown in the list, send the manufacturer part number, quantity or BOM to JIEXIN Electronics. Our team can assist with availability checks and quotation support.
| Photo | Mfr. Part # | Availability | Quantity | Datasheet | Series | Package/Case | Packaging | Product Status | Programmable | Type | Features | Memory Size | Time Format | Date Format | Interface | Voltage - Supply | Voltage - Supply, Battery | Current - Timekeeping (Max) | Operating Temperature | Mounting Type | Grade | Qualification | Supplier Device Package |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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PCF2123BS/1,512IC RTC CLK/CALENDAR SPI 16HVQFN |
3,472 |
|
Datasheet | - | 16-VFQFN Exposed Pad | Tube | Discontinued at Digi-Key | Not Verified | Clock/Calendar | Alarm, Leap Year, Square Wave Output, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | SPI | 1.6V ~ 5.5V | - | 0.33µA ~ 0.38µA @ 2V ~ 5V | -40°C ~ 85°C | Surface Mount | - | - | 16-HVQFN (3x3) |
|
PCF2129AT/1,518IC RTC CLOCK/CALENDAR I2C 20SO |
4,276 |
|
Datasheet | - | 20-SOIC (0.295", 7.50mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Square Wave Output, TCXO/Crystal, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 1.8V ~ 4.2V | 1.8V ~ 4.2V | 1.5µA @ 3.3V | -40°C ~ 85°C | Surface Mount | - | - | 20-SO |
|
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PCF2127AT/1,518IC RTC CLOCK/CALENDAR I2C 20SO |
1,962 |
|
Datasheet | - | 20-SOIC (0.295", 7.50mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Square Wave Output, SRAM, TCXO/Crystal, Watchdog Timer | 512B | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 1.8V ~ 4.2V | 1.8V ~ 4.2V | 1.5µA @ 3.3V | -40°C ~ 85°C | Surface Mount | - | - | 20-SO |
|
PCF8564ACX9/1,005IC RTC CLOCK/CALENDAR I2C DIE |
3,982 |
|
Datasheet | - | Die | Bulk | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Square Wave Output, Watchdog Timer | - | HH:MM:SS (24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 1V ~ 5.5V | - | 0.6µA ~ 0.75µA @ 2V ~ 5V | -40°C ~ 85°C | Surface Mount | - | - | Die |
|
RX-4801JE:UBIC RTC CLK/CALENDAR SPI 20VSOJ |
1,028 |
|
Datasheet | - | 20-LSSOJ (0.213", 5.40mm Width) | Bulk | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year | 16B | HH:MM:SS (24 hr) | YY-MM-DD-dd | SPI | 1.6V ~ 5.5V | - | 2.1µA ~ 3.4µA @ 3V ~ 5V | -40°C ~ 85°C | Surface Mount | - | - | 20-VSOJ |
|
PCF8523TS/1,112IC RTC CLK/CALENDAR I2C 14TSSOP |
4,191 |
|
Datasheet | - | 14-TSSOP (0.173", 4.40mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 1.6V ~ 5.5V | 1.8V ~ 5.5V | 0.5µA @ 2V ~ 5V | -40°C ~ 85°C | Surface Mount | - | - | 14-TSSOP |
|
ISL12027AIB27Z-TIC RTC CLK/CALENDAR I2C 8SOIC |
4,874 |
|
Datasheet | - | 8-SOIC (0.154", 3.90mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 8-SOIC |
|
ISL12027AIV27Z-TIC RTC CLK/CALENDAR I2C 8TSSOP |
2,795 |
|
Datasheet | - | 8-TSSOP (0.173", 4.40mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 8-TSSOP |
|
ISL12028AIB27Z-TIC RTC CLK/CALENDAR I2C 14SOIC |
2,355 |
|
Datasheet | - | 14-SOIC (0.154", 3.90mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-SOIC |
|
ISL12028AIV27Z-TIC RTC CLK/CALENDAR I2C 14TSSOP |
2,390 |
|
Datasheet | - | 14-TSSOP (0.173", 4.40mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-TSSOP |
|
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ISL12029AIB27Z-TIC RTC CLK/CALENDAR I2C 14SOIC |
3,886 |
|
Datasheet | - | 14-SOIC (0.154", 3.90mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-SOIC |
|
|
ISL12029AIV27Z-TIC RTC CLK/CALENDAR I2C 14TSSOP |
3,261 |
|
Datasheet | - | 14-TSSOP (0.173", 4.40mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-TSSOP |
|
ISL12027AIB27ZIC RTC CLK/CALENDAR I2C 8SOIC |
3,647 |
|
Datasheet | - | 8-SOIC (0.154", 3.90mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 8-SOIC |
|
|
ISL12027AIV27ZIC RTC CLK/CALENDAR I2C 8TSSOP |
3,453 |
|
Datasheet | - | 8-TSSOP (0.173", 4.40mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 8-TSSOP |
|
ISL12028AIB27ZIC RTC CLK/CALENDAR I2C 14SOIC |
1,326 |
|
Datasheet | - | 14-SOIC (0.154", 3.90mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-SOIC |
|
|
ISL12028AIV27ZIC RTC CLK/CALENDAR I2C 14TSSOP |
3,268 |
|
Datasheet | - | 14-TSSOP (0.173", 4.40mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-TSSOP |
|
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ISL12029AIB27ZIC RTC CLK/CALENDAR I2C 14SOIC |
3,366 |
|
Datasheet | - | 14-SOIC (0.154", 3.90mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-SOIC |
|
ISL12029AIV27ZIC RTC CLK/CALENDAR I2C 14TSSOP |
2,024 |
|
Datasheet | - | 14-TSSOP (0.173", 4.40mm Width) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year, Supervisor, Watchdog Timer | - | HH:MM:SS (12/24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 2.7V ~ 5.5V | 1.8V ~ 5.5V | 10µA ~ 20µA @ 2.7V ~ 5.5V | -40°C ~ 85°C | Surface Mount | - | - | 14-TSSOP |
|
RTC-7301DG:B ROHSIC RTC CLK/CALENDAR PAR 18DIP |
3,022 |
|
Datasheet | - | 18-DIP (0.300", 7.62mm) | Tube | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year | - | HH:MM:SS (24 hr) | YY-MM-DD-dd | Parallel | 2.4V ~ 5.5V | - | 1µA ~ 2µA @ 3V ~ 5V | -40°C ~ 85°C | Through Hole | - | - | 18-DIP |
|
RX-8581JE:B3 I2C-BUSIC RTC CLK/CALENDAR I2C 20VSOJ |
4,037 |
|
Datasheet | RX-8581JE | 20-LSSOJ (0.213", 5.40mm Width) | Tape & Reel (TR) | Obsolete | Not Verified | Clock/Calendar | Alarm, Leap Year | - | HH:MM:SS (24 hr) | YY-MM-DD-dd | I2C, 2-Wire Serial | 1.8V ~ 5.5V | - | 0.8µA ~ 1.2µA @ 3V ~ 5V | -40°C ~ 85°C | Surface Mount | - | - | 20-VSOJ |
Frequently Asked Questions
What are Real Time Clocks components used for?
Real Time Clocks components are used in a wide range of electronic equipment and systems. Their exact function depends on the device, circuit design and technical requirements of the application.
How do I choose the right Real Time Clocks part?
Compare the manufacturer part number, key specifications, package type, operating conditions, availability and datasheet information. For replacement projects, always verify the critical electrical and mechanical parameters before selecting an alternative.
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