M48T35-70MH1E STMICROELECTRONICS [STMicroelectronics], M48T35-70MH1E Datasheet
M48T35-70MH1E
Related parts for M48T35-70MH1E
M48T35-70MH1E Summary of contents
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... BCD coded year, month, day, date, hours, minutes, and seconds ■ Frequency test output for real time clock ■ Automatic power-fail chip deselect and WRITE protection ■ WRITE protect voltages (V = Power-fail Deselect Voltage): PFD – M48T35 4.75 to 5.5V CC – 4.5V V 4.75V PFD – M48T35Y 4.5 to 5.5V CC – 4. ...
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Contents 1 Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... The monolithic chip is available in two special packages to provide a highly integrated battery backed-up memory and real time clock solution. The M48T35 non-volatile pin and function equivalent to any JEDEC standard 32Kb x 8 SRAM. It also easily fits into many ROM, EPROM, and EEPROM sockets, providing the non-volatility of PROMs without any requirement for special WRITE timing or limitations on the number of WRITEs that can be performed ...
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... DQ4 DQ3 AI01621B A14 A12 A13 A11 M48T35Y A10 DQ7 DQ0 11 18 DQ6 DQ1 12 17 DQ5 DQ2 13 16 DQ4 DQ3 AI01622B ...
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Figure 4. Block diagram OSCILLATOR AND CLOCK CHAIN 32,768 Hz CRYSTAL LITHIUM CELL VOLTAGE SENSE POWER V PFD AND SWITCHING CIRCUITRY BiPORT SRAM ARRAY A0-A14 DQ0-DQ7 32,760 x 8 SRAM ARRAY ...
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... 2.1 Read mode The M48T35 the READ Mode whenever W (WRITE Enable) is high and E (Chip Enable) is low. The unique address specified by the 15 Address Inputs defines which one of the 32,768 bytes of data accessed. Valid data will be available at the Data I/O pins within Address Access time (t that the E and G access times are also satisfied ...
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... Write mode The M48T35 the WRITE Mode whenever W and E are low. The start of a WRITE is referenced from the latter occurring falling edge WRITE is terminated by the earlier rising edge The addresses must be held valid throughout the cycle must return high for a minimum of t prior to the initiation of another READ or WRITE Cycle ...
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... AVWL t Address Valid to Chip Enable Low AVEL 10/29 tAVAV VALID tAVWH tAVEL tWLWH tAVWL tWLQZ DATA INPUT tDVWH tAVAV VALID tAVEH tELEH tAVWL DATA INPUT tDVEH (1) Min after W falls. WLQZ tWHAX tWHQX tWHDX AI00926 tEHAX tEHDX AI00927 M48T35/Y Unit Max ...
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... RAM's content. At voltages below V user can be assured the memory will write protected state, provided the V is not less than tF. The M48T35/Y may respond to transient noise spikes on V into the deselect window during the time the device is sampling V of the power supply lines is recommended ...
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... The STOP Bit is the MSB of the seconds register. Setting '1' stops the oscillator. The M48T35/Y is shipped from STMicroelectronics with the STOP Bit set to a '1.' When reset to a '0,' the M48T35/Y oscillator starts within 1 second. ...
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... Hz. The devices are tested not to exceed 35 ppm (parts per million) oscillator frequency error at 25°C, which equates to about ±1.53 minutes per month. With the calibration bits properly set, the accuracy of each M48T35/Y improves to better than +1/–2 ppm at 25°C. The oscillation rate of any crystal changes with temperature (see Most clock chips compensate for crystal frequency and temperature shift error with cumbersome “ ...
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... Two methods are available for ascertaining how much calibration a given M48T35/Y may require. The first involves simply setting the clock, letting it run for a month and comparing known accurate reference (like WWV broadcasts) ...
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Figure 8. Crystal accuracy across temperature ppm 20 0 -20 -40 -60 -80 -100 0 Figure 9. Clock calibration NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION 3.6 V noise and negative going transients CC I transients, including those produced by output switching, ...
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MBRS120T3 is recommended for surface mount. Figure 10. Supply voltage protection 16/ 0.1 F DEVICE V SS AI02169 ...
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... Negative undershoots below –0.3V are not allowed on any pin while in the Battery Back-up mode. Caution: Do NOT wave solder SOIC to avoid damaging SNAPHAT sockets. Parameter Grade 1 Grade 6 Off, Oscillator Off) CC M48T35 M48T35Y M48T35 M48T35Y Value Unit °C – °C – °C 260 °C –0 – ...
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... Outputs deselected. 18/29 M48T35 ) 4. 100 1.5 5V DEVICE UNDER TEST includes JIG capacitance (1)(2) Parameter Min Input Capacitance Output Capacitance M48T35Y Unit 4.5 to 5.5 V – °C 100 1.5 V 1.9k OUT 100pF or 5pF AI01030 Max Unit ...
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... Outputs open – 0.2V CC –0.3 2 2.1mA –1mA 2 –40 to 85° 4.75 to 5.5V or 4.5 to 5.5V (except where A CC tFB tRB tDR DON'T CARE HIGH-Z M48T35Y Unit Max Min Max ±1 ±1 µA ±1 ±1 µ 0.8 –0.3 0 0.3 2 ...
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... V = 4.75 to 5.5V or 4.5 to 5.5V (except where A CC may result in deselection/write protection not occurring until 200µs after F may cause corruption of RAM data. FB (1)(2) M48T35 M48T35Y M48T35 M48T35Y Grade 1 Grade –40 to 85° 4.75 to 5.5V or 4.5 to 5.5V (except where A CC Min Max 0 ...
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Package mechanical information In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a Lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...
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Figure 14. SOH28 – 28-lead plastic small outline, 4-socket battery SNAPHAT, package outline B Note: Drawing is not to scale. Table 13. SOH28 – 28-lead plastic SO, 4-socket battery SNAPHAT, package mechanical data Symbol Typ ...
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Figure 15. SH – 4-pin SNAPHAT housing for 48mAh battery & crystal, package outline Note: Drawing is not to scale. Table 14. SH – 4-pin SNAPHAT housing for 48mAh battery & crystal, package mechanical data Symbol Typ ...
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Figure 16. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package outline Note: Drawing is not to scale. Table 15. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package mechanical data Symbol Typ ...
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Figure 17. PMDIP28 – 28-pin plastic DIP, hybrid, package outline Note: Drawing is not to scale. Table 16. PMDIP28 – 28-pin plastic DIP, hybrid, package mechanical data Symbol Typ 33. ...
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... TR = Tape & Reel (Not for New Design - Use F) For PCDIP28: blank = ECOPACK package, tubes 1. The M48T35 part is offered with the PCDIP28 (e.g., CAPHAT) package only. 2. The SOIC package (SOH28) requires the SNAPHAT separately under the part number “M4TXX-BR12SH” in plastic tube or “M4TXX-BR12SHTR” in Tape & ...
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Table 18. SNAPHAT battery table Part number M4T28-BR12SH Lithium Battery (48mAh) SNAPHAT M4T32-BR12SH Lithium Battery (120mAh) SNAPHAT Description Package SH SH 27/29 ...
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Revision history Table 19. Document revision history Date Revision Nov- 1999 1.0 07-Feb-2000 1.1 04-Jun-2001 2.0 31-Jul-2001 2.1 06-Mar-2002 2.2 20-May-2002 2.3 26-Jun-2002 2.4 31-Mar-2003 3.0 10-Dec-2003 4.0 31-Mar-2004 5.0 05-Dec20-05 6.0 01-Aug-2007 7.0 28/29 Changes First Issue t ...
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Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any ...