DS1346 MAXIM [Maxim Integrated Products], DS1346 Datasheet
DS1346
Related parts for DS1346
DS1346 Summary of contents
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... Rev 0; 8/11 Low-Current, SPI-Compatible Real-Time Clocks General Description The DS1346/DS1347 SPI™-compatible real-time clocks (RTCs) contain 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 devices ...
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Low-Current, SPI-Compatible Real-Time Clocks ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V CC All Other Pins to GND ................................-0. Current into Any Pin..........................................................±20mA Rate of Rise, V ............................................................100V/µs CC Continuous Power Dissipation (T = +70°C) A TDFN ...
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... CSS Time CRYSTAL CHARACTERISTICS PARAMETER SYMBOL Nominal Frequency f O Series Resistance ESR DS1346 Load Capacitance C L DS1347 Note 1: All parameters are 100% tested at T not production tested. is specified with DOUT open DIN = GND, SCLK = 4MHz at V Note Note 3: Timekeeping current is specified with Note 4: Guaranteed by design and not 100% production tested ...
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Low-Current, SPI-Compatible Real-Time Clocks (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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... In this configuration, the X1 pin is connected the external oscillator and the X2 pin is left unconnected. — EP Exposed Pad. Connect to GND or leave unconnected. _______________________________________________________________________________________ + SCLK DOUT DS1346 DS1347 DIN GND TDFN FUNCTION Pin Configuration Pin Description 5 ...
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... Low-Current, SPI-Compatible Real-Time Clocks X1 OSCILLATOR GND SCLK DIN INPUT SHIFT DOUT CS ALARM OUT 6 _______________________________________________________________________________________ 1Hz DIVIDER 32.768kHz DS1346 DS1347 CONTROL LOGIC REGISTERS ADDRESS REGISTER 31x 8 RAM ALARM CONTROL LOGIC Functional Diagram SECONDS MINUTES HOURS DATE MONTH DAY YEAR CONTROL CENTURY ...
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... Low-Current, SPI-Compatible Real-Time Clocks Detailed Description The DS1346/DS1347 are real-time clocks/calendars with an SPI-compatible interface and bits of SRAM. They provide seconds, minutes, hours, day of the week, date of the month, month, and year informa- tion, held in seven 8-bit timekeeping registers (see the Table 1 ...
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Low-Current, SPI-Compatible Real-Time Clocks 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 Clocks 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 Clocks 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 devices, a latch buffers each ...
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Low-Current, SPI-Compatible Real-Time Clocks 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 Clocks BIT 7 BIT 6 BIT MINUTES 0 1 BIT 7 BIT 6 12 BIT 7 BIT 6 BIT BIT 7 BIT 6 BIT ...
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Low-Current, SPI-Compatible Real-Time Clocks devices. SCLK, which is generated by the microcon- troller, is active only during address and data transfer to any device on the SPI bus. The inactive clock polari usually programmable on the microcontroller side ...
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Low-Current, SPI-Compatible Real-Time Clocks 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 Clocks 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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Low-Current, SPI-Compatible Real-Time Clocks GROUND PLANE VIA CONNECTION GUARD RING * * * GROUND PLANE VIA CONNECTION Figure 4. Crystal PCB Layout Chip Information PROCESS: CMOS 16 ______________________________________________________________________________________ * V PLANE CC 0.1μF VIA CONNECTION SM CAP * * * ...
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Low-Current, SPI-Compatible Real-Time Clocks REVISION REVISION NUMBER DATE 0 8/11 Initial release 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 ...