MCP7940N-I/SN Microchip Technology, MCP7940N-I/SN Datasheet
MCP7940N-I/SN
Specifications of MCP7940N-I/SN
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MCP7940N-I/SN Summary of contents
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... Using a low-cost 32.768 kHz crystal, it tracks time using several internal regis- ters. For communication, the MCP7940N uses the 2 I C™ bus. The clock/calendar automatically adjusts for months with fewer than 31 days, including corrections for leap years ...
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... MCP7940N FIGURE 1-1: TYPICAL OPERATING CIRCUIT X1 RTCC Time-Stamp/ SRAM Alarms Switch BAT BAT V SS DS25010A-page MFP 2 I C™ SCL SDA 2011 Microchip Technology Inc. ...
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... V s 1) 300 — — 1.3 5.5 V MCP7940N +1. -40°C to +85°C A Conditions — — 2.5V to 5.5V CC (Note OUT ...
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... MCP7940N TABLE 1-2: AC CHARACTERISTICS AC CHARACTERISTICS Param. Symbol Characteristic No Clock frequency CLK 2 T Clock high time HIGH 3 T Clock low time LOW 4 T SDA and SCL rise time R (Note SDA and SCL fall time F (Note Start condition hold time HD STA Start condition setup time ...
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... FIGURE 1-2: BUS TIMING DATA 5 SCL 7 3 SDA SDA Out 2011 Microchip Technology Inc MCP7940N DS25010A-page 5 ...
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... MCP7940N 2.0 PIN DESCRIPTIONS The descriptions of the pins are listed in FIGURE 2-1: DEVICE PINOUTS SOIC/DFN/MSOP/TSSOP Vcc MFP SCL BAT Vss 4 5 SDA 2.1 Serial Data (SDA) This is a bidirectional pin used to transfer addresses and data into and out of the device open-drain ...
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... NOT generating an Acknowledge bit on the last byte that has been clocked out of the slave. In this case, the slave (MCP7940N) will leave the data line high to enable the master to generate the Stop condition. (D) (D) ...
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... SDA bus, checking the device type identifier being transmitted. Upon receiving an ‘1101111’ code, the slave device outputs an Acknowledge signal on the SDA line. Depending on the state of the R/W bit, the MCP7940N will select a read or write operation. ADDRESS BYTE R/W X • ...
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... RTCC FUNCTIONALITY The MCP7940N family is a highly integrated RTCC. On-board time and date counters are driven from a low- power oscillator to maintain the time and date. An integrated V switch enables the device to maintain CC the time and date and also the contents of the SRAM during a V power failure ...
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... MCP7940N TABLE 4-1: RTCC MEMORY MAP Address Bit 7 Bit 6 Bit 5 1Ch 10 Minutes 1Dh 10 Hour 12/24 AM/PM 1Eh 10 Date 1Fh Day 4.1.1 RTCC REGISTER ADDRESSES 0x00h – Contains the BCD seconds and 10 seconds. The range 59. Bit 7 in this register is used to start or stop the on-board crystal oscillator. Setting this bit to a ‘ ...
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... Microchip Technology Inc. 4.2 FEATURES 4.2.1 CALIBRATION The MCP7940N utilizes digital calibration to correct for inaccuracies of the input clock source (either external or crystal). Calibration is enabled by setting the value of the Calibration register at address 08H. Calibration is achieved by adding or subtracting a number of input clock cycles per minute in order to achieve ppm level adjustments in the internal timing function of the MCP7940N ...
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... MCP7940N With bits RS1 and RS0 set to ‘00’, the calibration function can be expressed as (32768 +/- (2 * CALREG)) T output where clock period of MFP output signal output T = clock period of input signal input CALREG = decimal value of Calibration register setting and the sign is determined by the MSB of Calibration register ...
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... CC BAT 4.2.4 CRYSTAL SPECS The MCP7940N has been designed to operate with a standard 32 kHz crystal. Devices with a specified load capacitance of either 12pF or 6pF can be used. The end user should fully validate the chosen crystal across all the expected design parameters of the system to ensure correct operation ...
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... BUS ACTIVITY The 64 bytes of user SRAM are at location 0x20h and can be accessed during an RTCC update. Upon POR the SRAM will undefined state. Note: Entering an address past 5F for an SRAM operation will result in the MCP7940N not acknowledging the address. DS25010A-page 14 supply BAT S T CONTROL ...
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... To perform this type of read operation, first the word address must be set. This is done by sending the word address to the MCP7940N as part of a write operation (R/W bit set to ‘0’). After the word address is sent, the master generates a Start condition following the Acknowledge. ...
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... C K BUS ACTIVITY DS25010A-page 16 generate an Acknowledge but will generate a Stop condition. To provide sequential reads, the MCP7940N contains an internal Address Pointer which is incremented by one at the completion of each operation. This Address Pointer allows the entire memory contents to be serially read during one operation. The internal Address Pointer will automat- sequentially ically roll over to the start of the Block ...
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... Microchip Technology Inc. Example: 7940NI Example: Example: Example: 1st Line Marking Codes TSSOP MSOP TDFN 940N 7940NT AAV MCP7940N 1109 13F 940N I109 13F 7940NI 10913F AAV 109 DS25010A-page 17 ...
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... MCP7940N DS25010A-page 18 2011 Microchip Technology Inc. ...
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... Microchip Technology Inc. MCP7940N DS25010A-page 19 ...
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... MCP7940N DS25010A-page 20 2011 Microchip Technology Inc. ...
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... D N NOTE 2011 Microchip Technology Inc MCP7940N φ L DS25010A-page 21 ...
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... MCP7940N Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging DS25010A-page 22 2011 Microchip Technology Inc. ...
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... D N NOTE 2011 Microchip Technology Inc MCP7940N φ L DS25010A-page 23 ...
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... MCP7940N DS25010A-page 24 2011 Microchip Technology Inc. ...
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... Microchip Technology Inc. MCP7940N DS25010A-page 25 ...
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... MCP7940N DS25010A-page 26 2011 Microchip Technology Inc. ...
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... D N NOTE 2011 Microchip Technology Inc MCP7940N φ L DS25010A-page 27 ...
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... MCP7940N Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.com/packaging DS25010A-page 28 2011 Microchip Technology Inc. ...
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... APPENDIX A: REVISION HISTORY Revision A (04/2011) Original release of this document. 2011 Microchip Technology Inc. MCP7940N DS25010A-page 29 ...
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... MCP7940N NOTES: DS25010A-page 30 2011 Microchip Technology Inc. ...
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... Local sales offices are also available to help customers. A listing of sales offices and locations is included in the back of this document. Technical support is available through the web site at: http://microchip.com/support click on MCP7940N should contact their distributor, DS25010A-page 31 ...
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... Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Y Device: MCP7940N Questions: 1. What are the best features of this document? 2. How does this document meet your hardware and software development needs you find the organization of this document easy to follow? If not, why? 4 ...
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... C Serial RTCC d) MCP7940N-I/SN: Industrial Tempera Serial RTCC, ture, SOIC package. e) MCP7940N-I/MS: Industrial Tempera Serial RTCC ture MSOP package Serial RTCC f) MCP7940N-I/SN: Industrial Tempera- ture, SOIC package. g) MCP7940N-I/ST: Industrial Temperature, TSSOP package. h) MCP7940NT-I/ST: Industrial Temperature, TSSOP package, Tape and Reel. MCP7940N DS25010A-page 33 ...
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... MCP7940N NOTES: DS25010A-page 34 2011 Microchip Technology Inc. ...
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... PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. ...
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... Philippines - Manila Tel: 63-2-634-9065 Fax: 63-2-634-9069 Singapore Tel: 65-6334-8870 Fax: 65-6334-8850 Taiwan - Hsin Chu Tel: 886-3-6578-300 Fax: 886-3-6578-370 Taiwan - Kaohsiung Tel: 886-7-213-7830 Fax: 886-7-330-9305 Taiwan - Taipei Tel: 886-2-2500-6610 Fax: 886-2-2508-0102 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 2011 Microchip Technology Inc. 02/18/11 ...