DS1646-120+ Maxim Integrated Products, DS1646-120+ Datasheet
DS1646-120+
Specifications of DS1646-120+
Related parts for DS1646-120+
DS1646-120+ Summary of contents
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... DS164xP Timekeeping RAM Underwriters Laboratories (UL) Recognized ORDERING INFORMATION VOLTAGE PART RANGE (V) DS1646-120+ 5.0 DS1646P-120+ 5.0 +Denotes a lead(Pb)-free/RoHS-compliant package. *DS9034-PCX+ or DS9034I-PCX+ required (must be ordered separately). A “+" indicates a lead(Pb)-free product. The top mark will include a “+" symbol on lead(Pb)-free devices. ...
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... V BAT FUNCTION No Connection Address Input Data Input/Output Ground Active-Low Chip Enable Address Input Active-Low Output Enable Active-Low Write Enable Address Input Power-Supply Input Active-Low Power-Fail Output, Open Drain. Requires a pullup resistor for proper operation. Crystal Connection, V Battery Connection BAT DS1646/DS1646P ...
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... DESCRIPTION The DS1646 is a 128k x 8 nonvolatile static RAM with a full-function real time clock, which are both accessible in a byte-wide format. The nonvolatile timekeeping RAM is functionally equivalent to any JEDEC standard 128k x 8 SRAM. The device can also be easily substituted for ROM, EPROM and EEPROM, providing read/write nonvolatility and the addition of the real time clock function ...
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... The MSB Bit, B7, of the control register is the write bit. Setting the write bit like the read bit halts updates to the DS1646 registers. The user can then load them with the correct day, date and time data in 24-hour BCD format. Resetting the write bit then transfers those values to the actual clock counters and allows normal operation to resume ...
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... CLOCK ACCURACY (DIP MODULE) The DS1646 is guaranteed to keep time accuracy to within ±1 minute per month at 25°C. The RTC is calibrated at the factory by Dallas Semiconductor using nonvolatile tuning elements, and does not require additional calibration. For this reason, methods of field clock calibration are not available and not necessary ...
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... DS signal will be high during a write cycle. However, OE after WE WEZ > 4.5 volts) the DS1646 can be accessed as described above with CC is below the power-fail point V CC signal. At this time the power-fail output signal ( CE returns to nominal levels. When V ...
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... OUT Power-Fail Voltage TEMPERATURE SYMBOL MIN -0.3 IL SYMBOL MIN I CC1 I ) CC2 IH I CC3 2 4 DS1646/DS1646P ±10% (Over the Operating Range) TYP MAX UNITS NOTES 5 0.8 V (Over the Operating Range) TYP MAX UNITS NOTES 4.0 mA µA +1 µ 0.4 V 4.25 4 ...
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... WEW t WEZ DH1 t 25 DH2 SYMBOL MIN SYMBOL MIN Fall Time t 300 Rise Time REC DS1646/DS1646P (Over the Operating Range) TYP MAX UNITS NOTES ns 120 ns 120 100 +25°C) A TYP MAX UNITS NOTES (Over the Operating Range) TYP MAX UNITS NOTES µs µ ...
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... DS1646 READ CYCLE TIMING DS1646 WRITE CYCLE TIMING DS1646/DS1646P ...
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... POWER-DOWN/POWER-UP TIMING OUTPUT LOAD DS1646/DS1646P ...
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... RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE 32 EDIP 34 PCAP going high. WE going high. CE OUTLINE NO. MDF32+1 21-0245 PC2+6 21-0246 DS1646/DS1646P Note LAND PATTERN NO. — — ...
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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 © 2010 Maxim Integrated Products DESCRIPTION Maxim and the Dallas logo are a registered trademark of Maxim Integrated Products, Inc. DS1646/DS1646P PAGES CHANGED 1, 7 ...