M48T37Y-70MH1E STMicroelectronics, M48T37Y-70MH1E Datasheet
M48T37Y-70MH1E
Specifications of M48T37Y-70MH1E
M48T37Y-70MH1
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M48T37Y-70MH1E Summary of contents
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... CONTROL CIRCUIT, AND BATTERY FREQUENCY TEST OUTPUT FOR REAL TIME CLOCK SOFTWARE CALIBRATION YEAR 2000 COMPLIANT AUTOMATIC POWER-FAIL CHIP DESELECT and WRITE PROTECTION WATCHDOG TIMER WRITE PROTECT VOLTAGE (V = Power-Fail Deselect Voltage): PFD – M48T37Y 4.5 to 5.5V CC 4.2V V 4.5V PFD – M48T37V 3.0 to 3. ...
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... M48T37Y, M48T37V TABLE OF CONTENTS FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 1. Package SUMMARY DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 2. Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Table 1. Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 3. SOIC Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Figure 4. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 OPERATION MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 2. Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 READ Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 5. READ Mode AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 3. READ Mode AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 WRITE Mode Figure 6. WRITE Enable Controlled, WRITE AC Waveform Figure 7 ...
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... Figure 17.SH – 4-pin SNAPHAT Housing for 120mAh Battery & Crystal, Package Outline . . . . . . 26 Table 16. SH – 4-pin SNAPHAT Housing for 120mAh Battery & Crystal, Package Mech. Data PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 17. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 18. SNAPHAT Battery Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 REVISION HISTORY Table 19. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 M48T37Y, M48T37V 3/29 ...
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... M48T37Y, M48T37V SUMMARY DESCRIPTION The M48T37Y/V TIMEKEEPER x8 non-volatile static RAM and real time clock. The monolithic chip is available in a special package which provides a highly integrated battery backed- up memory and real time clock solution. The 44-lead, 330mil SOIC package provides sock- ets with gold-plated contacts at both ends for di- rect connection to a separate SNAPHAT housing containing the battery and crystal ...
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... Figure 3. SOIC Connections RST A14 5 40 IRQ/FT A12 A13 A11 M48T37Y NC 12 M48T37V WDI 14 31 A10 DQ7 DQ0 18 27 DQ6 DQ1 19 26 DQ5 DQ2 20 25 DQ4 DQ3 AI02174 M48T37Y, M48T37V 5/29 ...
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... M48T37Y, M48T37V Figure 4. Block Diagram IRQ/FT OSCILLATOR AND 32,768 Hz CRYSTAL LITHIUM CELL VOLTAGE SENSE V CC 6/29 WDI CLOCK CHAIN POWER V PFD AND SWITCHING CIRCUITRY RST BiPORT SRAM ARRAY A0-A14 32,752 x 8 DQ0-DQ7 SRAM ARRAY AI03253 ...
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... The information can be accessed by the user in the same manner as any other location in the static memory array. The M48T37Y/V also has its own Power-fail De- tect circuit. The control circuitry constantly moni- tors the single V condition. When V ...
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... M48T37Y, M48T37V READ Mode The M48T37Y the READ Mode whenever WRITE Enable (W) is high and Chip Enable (E) is low. The unique address specified by the 15 Ad- dress Inputs defines which one of the 32,752 bytes of data accessed. Valid data will be avail- able at the Data I/O pins within Address Access ...
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... WRITE Mode The M48T37Y the WRITE Mode whenever W and E are low. The start of a WRITE is refer- enced 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 ...
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... M48T37Y, M48T37V Table 4. WRITE Mode AC Characteristics Symbol Parameter t WRITE Cycle Time AVAV t Address Valid to WRITE Enable Low AVWL t Address Valid to Chip Enable Low AVEL t WRITE Enable Pulse Width WLWH t Chip Enable Low to Chip Enable High ELEH t WRITE Enable High to Address Transition ...
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... PFD PFD switches power to the internal battery which pre- serves data and powers the clock. The internal button cell will maintain data in the M48T37Y/V for an accumulated period of at least 7 years at room temperature when V tem power returns and V battery is disconnected and the power supply is switched to external V ...
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... The STOP Bit is the MSB of the seconds register. Setting '1' stops the oscillator. When reset to a '0,' the M48T37Y/V oscillator starts within one second. Note not necessary to set the WRITE Bit when setting or resetting the FREQUENCY TEST Bit (FT) or the STOP Bit (ST). ...
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... RB0-RB1 = Watchdog Resolution Bits WDS = Watchdog Steering Bit ABE = Alarm in Battery Back-Up Mode Enable Bit RPT1-RPT4 = Alarm Repeat Mode Bits WDF = Watchdog Flag (Read only Alarm Flag (Read only '0' and are Read only M48T37Y, M48T37V Function/Range BCD Format D1 D0 Year Year ...
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... It can also be programmed to go off while the M48T37Y the battery back-up mode of op- eration to serve as a system wake-up call. RPT1-RPT4 put the alarm in the repeat mode of operation. Table ...
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... ABE, AFE bit in Interrupt Register AF bit in Flags Register IRQ/FT Calibrating the Clock The M48T37Y/V is driven by a quartz controlled oscillator with a nominal frequency of 32,768 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 ...
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... Note: Accuracy of timer is within ± the selected resolution. If the processor does not reset the timer within the specified period, the M48T37Y/V sets the Watch- dog Flag (WDF) and generates a watchdog inter- 16/29 rupt or a microprocessor reset. WDF is reset by reading the Flags Register (Address 7FF0h). ...
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... Programmable Interrupts The M48T37Y/V provides two programmable in- terrupts: an alarm and a watchdog. When an inter- rupt condition occurs, the M48T37Y/V sets the appropriate flag bit in the Flag Register 7FF0h. The interrupt enable bits (AFE and ABE) in 7FF6h and the Watchdog Steering (WDS) Bit in 7FF7h al- low the interrupt to activate the IRQ/FT pin ...
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... M48T37Y, M48T37V V Noise And Negative Going Transients CC I transients, including those produced by output CC switching, can produce voltage fluctuations, re- sulting in spikes on the V bus. These transients CC can be reduced if capacitors are used to store en- ergy which stabilizes the V CC stored in the bypass capacitors will be released as low going spikes are generated or energy will be absorbed when overshoots occur ...
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... Figure 11. Crystal Accuracy Across Temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 –30 –20 Figure 12. Clock Calibration NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION F = -0.038 ppm ( – Temperature C M48T37Y, M48T37V AI00999 AI00594B 19/29 ...
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... M48T37Y, M48T37V MAXIMUM RATING Stressing the device above the rating listed in the “Absolute Maximum Ratings” table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicat the Operating sections of this specification is Table 8 ...
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... Conditions listed in the relevant tables. De- signers should check that the operating conditions in their projects match the measurement condi- tions when using the quoted parameters. Grade Grade 6 (1) 1.75V AI02325 (1,2) Parameter M48T37Y, M48T37V M48T37Y M48T37V 4.5 to 5.5 3 – – 100 ...
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... M48T37Y, M48T37V Table 11. DC Characteristics Symbol Parameter (2) Input Leakage Current I LI (2) Output Leakage Current Supply Current CC I Supply Current (Standby) TTL CC1 Supply Current (Standby) I CC2 CMOS (3) Input Low Voltage Input High Voltage IH Output Low Voltage (standard Output Low Voltage (open drain) ...
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... Rise Time 70°C or –40 to 85° may cause corruption of RAM data. FB (1) Parameter M48T37Y M48T37V M48T37Y M48T37V Grade 1 Grade 70°C or –40 to 85° M48T37Y, M48T37V tR tRB tREC VALID VALID AI03078 Min Max 300 200 = 4.5 to 5.5V or 3.0 to 3.6V (except where noted). ...
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... M48T37Y, M48T37V PACKAGE MECHANICAL INFORMATION Figure 15. SOH44 – 44-lead Plastic Small Outline, 4-socket SNAPHAT, Package Outline SOH-A Note: Drawing is not to scale. Table 14. SOH44 – 44-lead Plastic Small Outline, 4-socket SNAPHAT, Package Mech. Data Symb Typ 0. 24/ Min Max 3.05 0.05 0.36 2 ...
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... E mm Min Max 9.78 6.73 7.24 6.48 6.99 0.38 0.46 0.56 21.21 21.84 14.22 14.99 15.55 15.95 3.20 3.61 2.03 2.29 M48T37Y, M48T37V SHTK-A inches Typ Min Max 0.385 0.265 0.285 0.255 0.275 0.015 0.018 0.022 0.835 0.860 0.560 0.590 0.612 ...
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... M48T37Y, M48T37V Figure 17. SH – 4-pin SNAPHAT Housing for 120mAh Battery & Crystal, Package Outline Note: Drawing is not to scale. Table 16. SH – 4-pin SNAPHAT Housing for 120mAh Battery & Crystal, Package Mech. Data Symb Typ 26/ Min Max 10.54 8.00 8.51 7.24 8 ...
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... Table 18. SNAPHAT Battery Table Part Number M4T28-BR12SH Lithium Battery (48mAh) SNAPHAT M4T32-BR12SH Lithium Battery (120mAh) SNAPHAT M48T 37Y ® ), Tubes ® ), Tape & Reel ® battery package which is ordered separately under the part number “M4TXX- Description M48T37Y, M48T37V – Package SH SH 27/29 ...
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... M48T37Y, M48T37V REVISION HISTORY Table 19. Document Revision History Date Rev. # December 1999 1.0 First Issue From Preliminary Data to Data Sheet; Battery Low Flag paragraph changed; 100ns 07-Feb-00 2.0 speed class identifier changed (Tables 3, 4) 11-Jul-00 2.1 t changed (Table 12); watchdog timer paragraph changed ...
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