Product overview
Description
The M41T56 is a low-power, serial real-time clock (RTC) with 56 bytes of NVRAM. A built-in 32,768 Hz oscillator (external crystal controlled) and the first 8 bytes of the RAM are used for the clock/calendar function and are configured in binary coded decimal (BCD) format. Addresses and data are transferred serially via a two-line, bidirectional bus. The built-in address register is incremented automatically after each WRITE or READ data byte.
The M41T56 clock has a built-in power sense circuit which detects power failures and automatically switches to the battery supply during power failures. The energy needed to sustain the RAM and clock operations can be supplied from a small lithium coin cell.
Typical data retention time is in excess of 10 years with a 50 mAh, 3 V lithium cell. The M41T56 is supplied in an 8-lead plastic SOIC package.
-
All features
- Counters for seconds, minutes, hours, day, date, month, years, and century
- 32 KHz crystal oscillator integrating load capacitance (12.5 pF) providing exceptional oscillator stability and high crystal series resistance operation
- Serial interface supports I2C bus (100 kHz protocol)
- Ultra-low battery supply current of 450 nA (typ at 3 V)
- 5 V ±10% supply voltage
- Timekeeping down to 2.5 V
- Automatic power-fail detect and switch circuitry
- 56 bytes of general purpose RAM
- Software clock calibration to compensate crystal deviation due to temperature
- Automatic leap year compensation
- Operating temperature of –40 °C to 85 °C
- Available in an 8-lead, 150-mil, plastic SOIC (SO8)
- RoHS compliant
- Lead-free second level interconnect
Circuit Diagram
You might also like...
I2C code for Serial RTC
All tools & software
-
-
Part number Status Description Type Supplier Worldwide,Asia,Europe,Africa,North America,South America,Oceania,Afghanistan,Bahrain,Bangladesh,Bhutan,Brunei,Burma (Myanmar),Cambodia,China,East Timor,India,Indonesia,Iraq,Japan,Jordan,Kazakhstan,Kuwait,Kyrgyzstan,Laos,Malaysia,Maldives,Mongolia,Nepal,Oman,Pakistan,Philippines,Qatar,Russian Federation,Saudi Arabia,Singapore,South Korea,Sri Lanka,Taiwan,Tajikistan,Thailand,Turkmenistan,United Arab Emirates,Uzbekistan,Vietnam,Yemen,Albania,Andorra,Armenia,Austria,Azerbaijan,Belarus,Belgium,Bosnia and Herzegovina,Bulgaria,Croatia,Cyprus,Czech Republic,Denmark,Estonia,Finland,France,Georgia,Germany,Greece,Hungary,Iceland,Ireland,Israel,Italy,Latvia,Liechtenstein,Lithuania,Luxembourg,Macedonia,Malta,Moldova,Monaco,Montenegro,Netherlands,Norway,Poland,Portugal,Romania,San Marino,Serbia,Slovakia,Slovenia,Spain,Sweden,Switzerland,Turkey,Ukraine,United Kingdom,Vatican City,Algeria,Angola,Benin,Botswana,Burkina,Burundi,Cameroon,Cape Verde,Central African Republic,Chad,Comoros,Democratic Republic of Congo,Djibouti,Egypt,Equatorial Guinea,Eritrea,Ethiopia,Gabon,Gambia,Ghana,Guinea,Guinea-Bissau,Ivory Coast,Kenya,Lesotho,Liberia,Libya,Madagascar,Malawi,Mali,Mauritania,Mauritius,Morocco,Mozambique,Namibia,Niger,Nigeria,Rwanda,Sao Tome and Principe,Senegal,Seychelles,Sierra Leone,Somalia,South Africa,Swaziland,Tanzania,Togo,Tunisia,Uganda,Zambia,Zimbabwe,Antigua and Barbuda,Bahamas,Barbados,Belize,Canada,Costa Rica,Dominica,Dominican Republic,El Salvador,Grenada,Guatemala,Haiti,Honduras,Jamaica,Mexico,Nicaragua,Panama,Saint Kitts and Nevis,Saint Lucia,Saint Vincent and the Grenadines,Trinidad and Tobago,United States,Argentina,Bolivia,Brazil,Chile,Colombia,Ecuador,Guyana,Paraguay,Peru,Suriname,Uruguay,Venezuela,Australia,Fiji,Kiribati,Marshall Islands,Micronesia,Nauru,New Zealand,Palau,Papua New Guinea,Samoa,Solomon Islands,Tonga,Tuvalu,Vanuatu ActiveI2C code for Serial RTC
Clocks and timers software ST Worldwide,Asia,Europe,Africa,North America,South America,Oceania,Afghanistan,Bahrain,Bangladesh,Bhutan,Brunei,Burma (Myanmar),Cambodia,China,East Timor,India,Indonesia,Iraq,Japan,Jordan,Kazakhstan,Kuwait,Kyrgyzstan,Laos,Malaysia,Maldives,Mongolia,Nepal,Oman,Pakistan,Philippines,Qatar,Russian Federation,Saudi Arabia,Singapore,South Korea,Sri Lanka,Taiwan,Tajikistan,Thailand,Turkmenistan,United Arab Emirates,Uzbekistan,Vietnam,Yemen,Albania,Andorra,Armenia,Austria,Azerbaijan,Belarus,Belgium,Bosnia and Herzegovina,Bulgaria,Croatia,Cyprus,Czech Republic,Denmark,Estonia,Finland,France,Georgia,Germany,Greece,Hungary,Iceland,Ireland,Israel,Italy,Latvia,Liechtenstein,Lithuania,Luxembourg,Macedonia,Malta,Moldova,Monaco,Montenegro,Netherlands,Norway,Poland,Portugal,Romania,San Marino,Serbia,Slovakia,Slovenia,Spain,Sweden,Switzerland,Turkey,Ukraine,United Kingdom,Vatican City,Algeria,Angola,Benin,Botswana,Burkina,Burundi,Cameroon,Cape Verde,Central African Republic,Chad,Comoros,Democratic Republic of Congo,Djibouti,Egypt,Equatorial Guinea,Eritrea,Ethiopia,Gabon,Gambia,Ghana,Guinea,Guinea-Bissau,Ivory Coast,Kenya,Lesotho,Liberia,Libya,Madagascar,Malawi,Mali,Mauritania,Mauritius,Morocco,Mozambique,Namibia,Niger,Nigeria,Rwanda,Sao Tome and Principe,Senegal,Seychelles,Sierra Leone,Somalia,South Africa,Swaziland,Tanzania,Togo,Tunisia,Uganda,Zambia,Zimbabwe,Antigua and Barbuda,Bahamas,Barbados,Belize,Canada,Costa Rica,Dominica,Dominican Republic,El Salvador,Grenada,Guatemala,Haiti,Honduras,Jamaica,Mexico,Nicaragua,Panama,Saint Kitts and Nevis,Saint Lucia,Saint Vincent and the Grenadines,Trinidad and Tobago,United States,Argentina,Bolivia,Brazil,Chile,Colombia,Ecuador,Guyana,Paraguay,Peru,Suriname,Uruguay,Venezuela,Australia,Fiji,Kiribati,Marshall Islands,Micronesia,Nauru,New Zealand,Palau,Papua New Guinea,Samoa,Solomon Islands,Tonga,Tuvalu,Vanuatu ActiveSPI code -Serial RTC
Clocks and timers software ST
-
All resources
| Resource title | Version | Latest update |
|---|
Product Specifications (1)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 9.1 | 19 Sep 2016 | 19 Sep 2016 |
Application Notes (5 of 9)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 3.0 | 13 Sep 2018 | 13 Sep 2018 | ||
| 4.0 | 15 Feb 2015 | 15 Feb 2015 | ||
| 4.1 | 31 Oct 2024 | 31 Oct 2024 | ||
| 1.0 | 14 May 2015 | 14 May 2015 | ||
| 4.0 | 31 Oct 2024 | 31 Oct 2024 | ||
| 2.0 | 03 Apr 2013 | 03 Apr 2013 | ||
| 2.0 | 10 Oct 2022 | 10 Oct 2022 | ||
| 4.1 | 10 Oct 2022 | 10 Oct 2022 | ||
| 2.1 | 21 Jul 2017 | 21 Jul 2017 |
Brochures (2)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 1.0 | 09 Jun 2023 | 09 Jun 2023 | ||
| 2.0 | 01 Aug 2015 | 01 Aug 2015 |
Product Certifications (1)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| 1.0 | 10 Feb 2025 | 10 Feb 2025 |
EDA Symbols, Footprints and 3D Models
STMicroelectronics - M41T56
Speed up your design by downloading all the EDA symbols, footprints and 3D models for your application. You have access to a large number of CAD formats to fit with your design toolchain.
Please select one model supplier :
Symbols
Footprints
3D models
All resources
| Resource title | Version | Latest update |
|---|
IBIS models (1)
| Resource title | Version | Latest update | ||
|---|---|---|---|---|
| ZIP | 1.0 | 01 Aug 2015 | 01 Aug 2015 |
If you don't want to login now, you can download the CAD design file by simply providing your name and e-mail address in the form below and validating it.
This allows us to stay in contact and inform you about updates of this CAD design file.
For subsequent downloads this step will not be required for most of our CAD design files.
To validate your e-mail and start the download, please click on the link inside the e-mail that has been sent to you. This link will be valid for 24 hours. Please check your spam filters in case you did not receive the e-mail.
Unfortunately, the link you clicked didn't work. Don't worry, here are the steps you can take to get your download started:
If you still can't download the CAD design file, please reach out to us on the ST Community and we will help you- Ensure you are using the same browser used to made the initial request
- Check that cookies are allowed in your browser
- Update your browser to its latest version
- Please also note that links forwarded by somebody else will not work
The e-mail address that you have entered during the download attempt has not yet been validated. Please check your inbox for the e-mail with the download link. In case you did not receive the e-mail, or you entered a wrong e-mail address, you can start-over the process.
Quality and Reliability
| Part Number | Marketing Status | Package | Grade | RoHS Compliance Grade | Material Declaration** |
|---|---|---|---|---|---|
| M41T56M6F | Active | SO-8 | Industrial | Ecopack3 | |
Marketing Status
Package
SO-8
Grade
Industrial
RoHS Compliance Grade
Ecopack3
(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.
Sample & Buy
| Part Number | Marketing Status | Budgetary Price (US$)*/Qty | Order from ST | Order from distributors | Package | Packing Type | RoHS | Country of Origin | ECCN (US) | ECCN (EU) | Operating temperature (°C) | Operating Temperature (°C) (max) | NVRAM size (B) | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| min | max | ||||||||||||||||||||||||||||||||||||||||||||||||
| M41T56M6F | Active | 1.3946 / 10k | Available at 5 distributors Distributor availability of M41T56M6F
Distributor reported inventory date: 4/16/2025 | | | | Buy from Distributor | | SO-8 | Tape and Reel | MOROCCO | EAR99 | NEC | -40 | 85 | 56 | |||||||||||||||||||||||||||||||||
M41T56M6F Active
Part Number:
M41T56M6F
Operating Temperature (°C)
Min:
-40
Max:
85
NVRAM size (B):
56
Farnell Element14
Stock
6071Min.Order
1MOUSER
Stock
2861Min.Order
1FUTURE
Stock
2500Min.Order
0DIGIKEY
Stock
7839Min.Order
1Newark Element14
Stock
1716Min.Order
0Distributor reported inventory date: 4/16/2025
Stock
Min.Order
(*) Suggested Resale Price (USD) per defined quantity for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office or our Distributors