DS1216 Maxim, DS1216 Datasheet
DS1216
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DS1216 Summary of contents
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... GENERAL DESCRIPTION The DS1216 SmartWatch RAM and SmartWatch ROM sockets are 600-mil-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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... DQ0 GND 14 DS1216B/C/E 28-Pin Intelligent Socket SELECTOR GUIDE PART RAM/ROM DS1216B RAM DS1216C RAM DS1216D RAM DS1216E ROM DS1216F ROM DS1216H RAM - Output Enable, Active Low OE - Write Enable, Active Low Switched Switched Switched V CC ...
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... DETAILED DESCRIPTION The DS1216 SmartWatch RAM and SmartWatch ROM Sockets are 600-mil-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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If a match is not found, the pointer does not advance and all subsequent write cycles are ignored read cycle occurs at any time during pattern recognition, the present sequence ...
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... THIS PATTERN IS SENT TO THE SMARTWATCH LSB TO MSB. 19 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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... Registers contain one or more bits that always read logic 0. When writing these locations, a logic acceptable. ADDITIONAL INFORMATION Refer to Application Note 52: Using the Dallas Phantom Real-Time Clocks (available on our website at www.maxim-ic.com/RTCapps) for information about using regarding optional modifications and the phantom clock contained within the SmartWatch ...
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... In this case, the socket will ignore the RST input, preventing address transitions from resetting the pattern match, even if the RST bit is enabled. On the DS1216B and DS1216D, the two V V from the controller is connected to the two V CC modifications are required if the lower density RAM is used ...
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Figure 3. SmartWatch Register Definition REGISTER 12/ 0.1 SEC 10 SEC 10 MIN OSC ...
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... Note: Wave or hand-solder only. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time can affect reliability. RECOMMENDED OPERATING CONDITIONS (T = 0° ...
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CAPACITANCE (T = +25°C) A PARAMETER Input Capacitance Output Capacitance Expected Data Retention AC ELECTRICAL CHARACTERISTICS (V = 4.5V to 5.5V 0°C to +70°C PARAMETER Read Cycle Time CE Access Time OE Access Time CE to ...
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Timing Diagram: Read Cycle to SmartWatch Timing Diagram: Write Cycle to SmartWatch ...
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Timing Diagram: Reset for SmartWatch Timing Diagram: Power-Down CE (L (U) V (L) CC *Note 1 Timing Diagram: Power- (max ...
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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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... PACKAGE INFORMATION 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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... AM-PM/12-/24-MODE, and Absolute Maximum Ratings sections 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 © ...