Real Time Clocks
Browse available Real Time Clocks part numbers with manufacturer references, stock information, pricing, datasheets and key specifications. Use the table below to compare options for your project.
For BOM, shortage or hard-to-find requirements, send your part number and quantity to Winsun (HK) Electronics for availability, lead-time and quotation support.
| Photo | Mfr. Part # | Availability | Price | 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 |
|
|
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 |
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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 |
|
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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 |
|
|
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 |
Real Time Clocks FAQ
Common questions about selecting, comparing and sourcing Real Time Clocks components through Winsun (HK) Electronics.
What should I check when selecting Real Time Clocks components?
Compare the manufacturer part number, electrical specifications, package, operating conditions and application requirements. The product datasheet should be used to confirm technical suitability.
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Yes. Send the exact part number, manufacturer and required quantity. Winsun (HK) Electronics can assist with availability checks, quotation support and sourcing options based on your requirement.
Do you support shortage, obsolete or hard-to-find Real Time Clocks parts?
Yes. Our sourcing team can review shortage and obsolete-part requirements and help check available supply channels or possible alternatives when appropriate.
How do I request a quote for Real Time Clocks components?
Submit an RFQ with the part number, manufacturer, quantity and target delivery requirement. Our sales team will review your request and follow up with current sourcing information.
