DS1216 Dallas Semiconductor, DS1216 Datasheet
DS1216
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DS1216 Summary of contents
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... RAM data § Watch function is transparent to RAM operation § Month and year determine the number of days in each month; leap-year compensation valid up to 2100 ORDERING INFORMATION DS1216B, DS1216C, DS1216D, DS1216E, DS1216F, DS1216H (See Figure 2 for letter suffix marking identification.) PIN DESCRIPTION - RST ...
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... Intelligent Socket DESCRIPTION The DS1216 SmartWatch RAM and SmartWatch ROM Sockets are 600mil-wide DIP sockets with a built-in CMOS watch function RAM controller circuit, and an embedded lithium energy source. The sockets provide an NV RAM solution for memory sized from 512k x 8 with package sizes from 26 pins to 32 pins ...
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After the pattern match, the next 64 reads and/or writes are directed to the clock, and the RAM is disabled. Once the pattern is established, the next 64 read/write cycles will be directed to the RTC registers. When power is ...
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... RAM would otherwise be expected. NONVOLATILE CONTROLLER OPERATION The DS1216 SmartWatch performs circuit functions required to make a CMOS RAM nonvolatile. First, a switch is provided to direct power from the battery or V This switch has a voltage drop of less than 0.2V. The second function that the SmartWatch provides is power-fail detection, which occurs at V goes out of tolerance, a comparator outputs a power-fail signal to the chip-enable logic ...
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SMARTWATCH REGISTER INFORMATION The SmartWatch information is contained in eight registers of 8 bits, each of which is sequentially accessed one bit at a time after the 64-bit pattern recognition sequence has been completed. When updating the SmartWatch registers, each ...
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... RST bit is RESET enabled. On the DS1216B and DS1216D, the two V from the controller is connected to the two V are required if the lower density RAM is used. To use the higher density RAM, the trace by the lower density RAM V pin, identified by a hash mark labeled “ ...
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SMARTWATCH REGISTER DEFINITION Figure 3 REGISTER 7 0.1 SEC 12/ YEAR 7 0.01 SEC 10 ...
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ABSOLUTE MAXIMUM RATINGS* Voltage Range on any Pin Relative to Ground Operating Temperature Range Storage Temperature Range Soldering Temperature Range * This is a stress rating only and functional operation of the device at these or any other conditions beyond ...
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CAPACITANCE PARAMETER Input Capacitance Output Capacitance PARAMETER Expected Data Retention AC ELECTRICAL CHARACTERISTICS PARAMETER Read Cycle Time CE Access Time OE Access Time CE to Output Low Output Low Output High Output High-Z Address ...
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TIMING DIAGRAM: READ CYCLE TO SMARTWATCH TIMING DIAGRAM: WRITE CYCLE TO SMARTWATCH TIMING DIAGRAM: RESET FOR SMARTWATCH ...
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TIMING DIAGRAM: POWER-DOWN TIMING DIAGRAM: POWER-UP Warning: Under no circumstances should negative undershoots of any amplitude be allowed when the device is in battery-backup mode. Water washing for flux removal will discharge internal lithium source because exposed voltage pins are ...
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... Expected data retention time (time while on battery) for a given RAM battery current can be calculated using the following formula: 0.045 / (current in amps) = data retention time in hours 15) The DS1216 products are shipped with the battery-backup power off. First power-up switches backup battery on to clock and RAM V or left disconnected at the PC board. ...
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... DS1216 28 SMARTWATCH PKG 28-PIN DIM MIN A IN. 1.390 1.420 1.580 1.620 MM 35.31 36.07 40.13 41.14 B IN. 0.690 0.720 0.690 0.720 17.53 18.29 17.53 18. IN. 0.420 0.470 0.400 0.470 10.67 11.94 10.16 11. IN. 0.035 0.065 0.035 0.065 MM 0.89 E IN. 0.055 0.075 0.055 0.075 1 ...