DS1347 Maxim, DS1347 Datasheet
DS1347
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DS1347 Summary of contents
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... Rev 2; 2/12 Low-Current, SPI-Compatible Real-Time Clock General Description The DS1347 SPI-compatible real-time clock (RTC) con- tains a real-time clock/calendar and bits of static random-access memory (SRAM). The real-time clock/calendar provides seconds, minutes, hours, day, date, month, year, and century information. A time/date programmable polled ALARM is included in the device. ...
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... TDFN (derate 24.4mW/°C above +70°C)...................1.375mW Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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Low-Current, SPI-Compatible Real-Time Clock AC ELECTRICAL CHARACTERISTICS (V = +2.0V to +5.5V -40°C to +85°C. Typical values are (Figure 5, Notes 1, 5) PARAMETER SYMBOL SPI SERIAL TIMING Input Rise Time t DIN, SCLK, ...
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Low-Current, SPI-Compatible Real-Time Clock (T = +25°C, unless otherwise noted.) A SUPPLY CURRENT vs. SUPPLY VOLTAGE 120 T = +25° 0mA, OUT 100 CS = DIN = GND 1MHz SCLK 20 0 ...
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... V Power-Supply Input Connections for Standard 32.768kHz Quartz Crystal (see the Crystal Characteristics table — EP Exposed Pad. Connect to GND or leave unconnected. _______________________________________________________________________________________ + SCLK DOUT DS1347 DIN GND TDFN FUNCTION Pin Configuration Pin Description 5 ...
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... Low-Current, SPI-Compatible Real-Time Clock X1 OSCILLATOR 32.768kHz GND SCLK DIN INPUT SHIFT REGISTERS DOUT CS ALARM OUT 6 _______________________________________________________________________________________ 1Hz DIVIDER DS1347 CONTROL LOGIC ADDRESS REGISTER 31x 8 RAM ALARM CONTROL LOGIC Functional Diagram SECONDS MINUTES HOURS DATE MONTH DAY YEAR CONTROL CENTURY ALARM ...
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... Low-Current, SPI-Compatible Real-Time Clock Detailed Description The DS1347 is a real-time clock/calendar with an SPI- compatible interface and bits of SRAM. It pro- vides seconds, minutes, hours, day of the week, date of the month, month, and year information, held in seven 8-bit timekeeping registers (see the Functional Table 1 ...
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Low-Current, SPI-Compatible Real-Time Clock Table 1. Register Map (continued) ADDRESS BIT 7 BIT 6 BIT 5 57h X X 59h X X 5Bh X X 5Dh X X 5Fh X X 61h X X 63h X X 65h X X ...
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Low-Current, SPI-Compatible Real-Time Clock Setting the Clock Writing to the Timekeeping Registers The time and date are set by writing to the timekeeping registers (Seconds, Minutes, Hours, Date, Month, Day, Year, and Century). During a write operation, an input buffer ...
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Low-Current, SPI-Compatible Real-Time Clock Reading the Clock Reading the Timekeeping Registers The main timekeeping registers (Seconds, Minutes, Hours, Date, Month, Day, Year) can be read with either single reads or a burst read. In the device, a latch buffers each ...
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Low-Current, SPI-Compatible Real-Time Clock BIT 7 BIT 6 BIT WP: Write-Protect RAM. If the WP bit is logic one, writing to the 31 bytes of RAM is inhibited. This bit is cleared BIT ...
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Low-Current, SPI-Compatible Real-Time Clock BIT 7 BIT 6 BIT MINUTES 0 1 BIT 7 BIT 6 BIT 5 12 BIT 7 BIT 6 BIT BIT 7 BIT ...
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Low-Current, SPI-Compatible Real-Time Clock microcontroller, is active only during address and data transfer to any device on the SPI bus. The inactive clock polarity is usually programmable on the microcontroller side of the SPI interface. In the device, input data ...
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Low-Current, SPI-Compatible Real-Time Clock CS SCLK DIN R ADDRESS/COMMAND BYTE HIGH IMPEDANCE DOUT Figure 2a. Single Read CS SCLK DIN R ADDRESS/COMMAND BYTE* HIGH IMPEDANCE DOUT *ONLY ONE ADDRESS/COMMAND BYTE IS ...
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Low-Current, SPI-Compatible Real-Time Clock CS serves two functions. First, CS turns on the control logic that allows access to the Shift register for address/command and data transfer. Second, CS pro- vides a method of terminating either single-byte or mul- tiple-byte ...
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... LAYER 1 TRACE For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed ...