The MCP7940N series of low-power Real-Time Clocks (RTC) uses digital timing compensation for an accurate clock/calendar, a programmable output control for versatility, and a power sense circuit that automatically switches to the backup supply. Using a low-cost 32.768 kHz crystal, it tracks time using several internal registers. For communication, the MCP7940N uses the I2C™ bus. The clock/calendar automatically adjusts for months with fewer than 31 days, including corrections for leap years. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator and settable alarm(s) to the second, minute, hour, day of the week, date or month. Using the programmable CLKOUT, frequencies of 32.768, 8.192 and 4.096 kHz and 1 Hz can be generated from the external crystal. The device is fully accessible through the serial interface while VCC is between 1.8V and 5.5V, but can operate down to 1.3V for timekeeping and SRAM retention only.
产品特性
| 技术参数
|
MCP7940N Low-Cost I2C Real-Time Clock/Calendar with SRAM and Battery Switchover | Data Sheets | 03/20/2014 | 1351KB | |
MCP7940N Family Silicon Errata | Errata | 12/15/2015 | 70KB | |
Maxim DS1307 to MCP7940N Migration | Migration Documents | 03/07/2013 | 326KB | |
Maxim DS1338 to MCP7940N Migration | Migration Documents | 03/28/2013 | 317KB | |
ST M41T11 to MCP7940N Migration | Migration Documents | 04/09/2013 | 344KB | |
AN1355 - A Complete Electronic Watch Based on MCP79410 I2C? RTCC | AppNote | 06/23/2016 | 154KB | |
AN1364 - Using the Alarm Feature on the MCP79410 RTCC to Implement a Delayed Alarm | AppNote | 10/20/2010 | 123KB | |
AN1365 - Recommended Usage of Microchip Serial RTCC Devices | AppNote | 03/28/2013 | 267KB | |
AN1413 - Temperature Compensation of a Tuning Fork Crystal Based on MCP79410 | AppNote | 11/07/2011 | 479KB | |
AN1414 - Using HI-TECH C Compiler to Interface RTCC Devices to 8-Bit PIC MCUs | AppNote | 01/31/2012 | 4847KB | |
AN1491 - Configuring the MCP794XX RTCC Family | AppNote | 01/25/2013 | 246KB | |
AN1496 - Debugging Stand-Alone Real-Time Clock/Calender-based Applications | AppNote | 02/22/2013 | 215KB | |
AN1519 - Recommended Crystals for Microchip Stand-Alone Real-Time Clock/Calendar Devices | AppNote | 09/16/2013 | 397KB | |
AN2027 - Backup Power Sources for Microchip's RTCCs and SRAMs | AppNote | 12/01/2015 | 161KB | |
TB3116 - Questions and Answers Concerning MCP79XXX Serial RTCCs | AppNote | 08/11/2014 | 75KB | |
Enabling Intelligent Automation Using the MCP7941X I2C RTCC | Tech Briefs | 10/21/2010 | 74KB | |
I2C & SPI Real-Time Clock/Calendar Sell Sheet | Brochures | 07/21/2014 | 703KB | |
MCP794xx I2C Real-Time Clock/Calendar Brochure | Brochures | 10/27/2010 | 141KB | |
MCP794xx Reference Layout Gerber Files | Gerber Files | 05/25/2011 | 50KB | |
AN1355 PIC18F Source Code | Sample Code | 08/21/2012 | 61KB | |
AN1355 PIC24F Source Code | Sample Code | 08/21/2012 | 152KB |
Part Number | Leads | Package Type | Temp Range | Packing | 1+ | 26+ | 100+ | 1000+ | 5000+ |
---|---|---|---|---|---|---|---|---|---|
MCP7940N-E/MS | 8 | MSOP | -40C to +125C | TUBE | 0.84 | 0.78 | 0.74 | 0.69 | 0.67 |
MCP7940N-E/SN | 8 | SOIC | -40C to +125C | TUBE | 0.80 | 0.74 | 0.70 | 0.66 | 0.64 |
MCP7940N-I/MS | 8 | MSOP | -40C to +85C | TUBE | 0.78 | 0.72 | 0.68 | 0.64 | 0.62 |
MCP7940N-I/P | 8 | PDIP | -40C to +85C | TUBE | 0.80 | 0.74 | 0.70 | 0.66 | 0.64 |
MCP7940N-I/SN | 8 | SOIC | -40C to +85C | TUBE | 0.74 | 0.68 | 0.65 | 0.61 | 0.59 |
MCP7940N-I/ST | 8 | TSSOP | -40C to +85C | TUBE | 0.78 | 0.72 | 0.68 | 0.64 | 0.62 |
MCP7940NT-E/MS | 8 | MSOP | -40C to +125C | T/R | 0.84 | 0.78 | 0.74 | 0.69 | 0.67 |
MCP7940NT-E/SN | 8 | SOIC | -40C to +125C | T/R | 0.80 | 0.74 | 0.70 | 0.66 | 0.64 |
MCP7940NT-I/MNY | 8 | TDFN | -40C to +85C | T/R | 0.82 | 0.76 | 0.72 | 0.68 | 0.66 |
MCP7940NT-I/MS | 8 | MSOP | -40C to +85C | T/R | 0.78 | 0.72 | 0.68 | 0.64 | 0.62 |
MCP7940NT-I/SN | 8 | SOIC | -40C to +85C | T/R | 0.74 | 0.68 | 0.65 | 0.61 | 0.59 |
MCP7940NT-I/ST | 8 | TSSOP | -40C to +85C | T/R | 0.78 | 0.72 | 0.68 | 0.64 | 0.62 |
Product | Price5K |
---|---|
MCP79400 | $0.66 |
MCP79401 | $0.72 |
MCP79402 | $0.72 |
MCP7940M | $0.46 |
MCP7940N | $0.59 |
MCP79410 | $0.72 |
MCP79411 | $0.78 |
MCP79412 | $0.78 |
MCP79510 | $0.90 |
MCP79511 | $0.96 |
MCP79512 | $0.96 |
MCP79520 | $0.96 |
MCP79521 | $1.02 |
MCP79522 | $1.02 |
MCP795W10 | $1.22 |
MCP795W11 | $1.28 |
MCP795W12 | $1.28 |
MCP795W20 | $1.28 |
MCP795W21 | $1.34 |
MCP795W22 | $1.34 |
PartNumber | DeviceWeight | ShippingWeight | LeadCount | PackageType | PackageWidth | SolderComposition | JEDECIndicator | RoHS | ChinaEFUP |
---|---|---|---|---|---|---|---|---|---|
MCP7940N-I/P | 0.486700 | 0.900000 | 8 | PDIP | .300in | Matte Tin | e3 | ||
MCP7940N-I/SN | 0.078000 | 0.160000 | 8 | SOIC | .150In(3.90mm) | Matte Tin | e3 | ||
MCP7940NT-I/SN | 0.078000 | 0.230303 | 8 | SOIC | .150In(3.90mm) | Matte Tin | e3 | ||
MCP7940NT-I/SNV01 | 0.078000 | 0.230303 | 8 | SOIC | .150In(3.90mm) | Matte Tin | e3 | ||
MCP7940N-E/SN | 0.078000 | 0.160000 | 8 | SOIC | .150In(3.90mm) | Matte Tin | e3 | ||
MCP7940NT-E/SN | 0.078000 | 0.230303 | 8 | SOIC | .150In(3.90mm) | Matte Tin | e3 | ||
MCP7940N-I/ST | 0.033000 | 0.090000 | 8 | TSSOP | 4.4mm | Matte Tin | e3 | ||
MCP7940NT-I/ST | 0.033000 | 0.215600 | 8 | TSSOP | 4.4mm | Matte Tin | e3 | ||
MCP7940N-I/MS | 0.025600 | 0.070000 | 8 | MSOP | 3x3mm | Matte Tin | e3 | ||
MCP7940NT-I/MS | 0.025600 | 0.215600 | 8 | MSOP | 3x3mm | Matte Tin | e3 | ||
MCP7940N-E/MS | 0.025600 | 0.070000 | 8 | MSOP | 3x3mm | Matte Tin | e3 | ||
MCP7940NT-E/MS | 0.025600 | 0.215600 | 8 | MSOP | 3x3mm | Matte Tin | e3 | ||
MCP7940NT-I/MNY | 0.014300 | 0.248485 | 8 | TDFN | 2x3x0.8mm | NiPdAu | e4 |