m48t36 STMicroelectronics, m48t36 Datasheet
m48t36
Related parts for m48t36
m48t36 Summary of contents
Page 1
... INTEGRATED ULTRA LOW POWER SRAM, REAL TIME CLOCK, POWER-FAIL CONTROL CIRCUIT and BATTERY FREQUENCY TEST OUTPUT for REAL TIME CLOCK AUTOMATICPOWER-FAIL CHIP DESELECTand WRITE PROTECTION WRITE PROTECT VOLTAGE: – M48T36Y: 4.2V V 4.5V PFD SMALL OUTLINE PACKAGE PROVIDES DIRECT CONNECTION for a SNAPHAT HOUSING CONTAINING the BATTERY and CRYSTAL ...
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... SO, the battery package (i.e. SNAPHAT) part number is ”M4T44-BR12SH1”. As Figure 3 shows, the static memory array and the quartz controlled clock oscillator of the M48T36 are integrated on one silicon chip. The two circuits are interconnectedat the upper eight memory locations to provide user accessible BYTEWIDE clock in- formation in the bytes with addresses 7FF9h- 7FFFh ...
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... BATTERY LOW 32,752 x 8 SRAM ARRAY V PFD RST DQ0-DQ7 X X High OUT V V High High High Z M48T36 A0-A14 DQ0-DQ7 AI01626 Power Standby Active Active Active CMOS Standby Battery Back-up Mode 3/17 ...
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... M48T36 AC MEASUREMENT CONDITIONS Input Rise and Fall Times 5ns Input Pulse Voltages Input and Output Timing Ref. Voltages 1.5V Note that Output Hi-Z is defined as the point where data is no longer driven. (1, 2) Table 4. Capacitance ( MHz ) A Symbol Parameter C Input Capacitance IN (3) ...
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... Table 6. Power Down/Up Trip Points DC Characteristics Symbol Parameter V Power-fail Deselect Voltage (M48T36Y) PFD V Battery Back-up Switchover Voltage SO (2) t Expected Data Retention Time DR Notes: 1. All voltages referenced Table 7. Power Down/Up Mode AC Characteristics (T Symbol Parameter before Power Down ...
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... Address Transition to Output Transition AXQX Notes 100pF (see Figure 4 5pF (see Figure 4). L Figure 6. Read Mode AC Waveforms A0-A14 tAVQV E tELQX G DQ0-DQ7 Note: Write Enable (W) = High 6/17 M48T36Y Min tAVAV VALID tELQV tGLQV tGHQZ tGLQX VALID Unit -70 Max ns ...
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... READ MODE The M48T36 is in 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 ...
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... M48T36 Figure 7. Write Enable Controlled, Write AC Waveforms A0-A14 tAVEL E tAVWL W DQ0-DQ7 Figure 8. Chip Enable Controlled, Write AC Waveforms A0-A14 tAVEL E tAVWL W DQ0-DQ7 8/17 tAVAV VALID tAVWH tWLWH tWLQZ tWHQX tWHDX DATA INPUT tDVWH tAVAV VALID tAVEH tELEH tEHDX DATA INPUT tDVEH tWHAX AI00926 ...
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... Time) but will go indeterminate until the next Ad- dress Access. WRITE MODE The M48T36 is in the Write Mode whenever W and E are low. The start of a write is referencedfrom the latter occurring falling edge write is terminated by the earlier rising edge The addresses must be held valid throughoutthe cycle ...
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... The STOP bit is the MSB of the seconds register. Setting ’1’ stops the oscillator. The M48T36 is shipped from SGS-THOMSON with the STOP bit set to a ’1’. Data ...
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... When reset to a ’0’, the M48T36 oscillator starts within 1 second. Calibrating the Clock The M48T36 is driven by a quartz controlled oscil- lator with a nominal frequency of 32,768 Hz. The devices are tested not to exceed 35 PPM (parts per million) oscillator frequency error which equates to about 1 ...
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... The alarm can be configured to go off at a pre- scribed time on a specific day of the month or repeat every day, hour, minute, or second. It can also be programmed to go off while the M48T36 is in the battery back-up mode of operation to serve as a system wake-up call. RPT1-RPT4 put the alarm in the repeat mode of operation ...
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... Watchdog Register = seconds). If the processor does not reset the timer within the specified period, the M48T36 sets the WDF (Watchdog Flag) and generates a watch- dog interrupt or a microprocessor reset. The most significant bit of the Watchdog Register is the Watchdog Steering Bit. When set to a ’ ...
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... M48T36 ORDERING INFORMATION SCHEME Example: M48T36Y Supply Voltage and Write Protect Voltage 36Y V = 4.5V to 5.5V - 4.2V to 4.5V PFD The SO and battery packages are shipped separately in plastic anti-static tubes. The SO package is also available to ship in Tape & Reel form. For the 44 lead SO, the battery package (i.e. SNAPHAT) part number is ” ...
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... SOH Drawing is not to scale Max Typ 3.05 0.36 2.69 0.51 0.32 – – 8.89 – 0.050 3.61 12.70 1. M48T36 inches Min Max 0.120 0.002 0.014 0.092 0.106 0.014 0.020 0.006 0.012 – – 0.324 0.350 – – 0.126 0.142 0.453 0.500 0.016 0.050 ...
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... M48T36 SH44 - SNAPHAT Housing for 44 lead Plastic Small Outline mm Symb Typ Min A A1 6. 0.46 D – – E 14.22 eA – – eB 3.20 L 2.03 SH44 eA D Drawing is not to scale 16/17 inches Max Typ Min 9.78 7.24 0.265 6.99 0.255 0.38 0.56 0.018 – – – 14.99 0.560 – – – 3.61 0.126 2 ...
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... SGS-THOMSON Microelectronics - All Rights Reserved TIMEKEEPER, SNAPHAT, BYTEWIDE and BiPORT are trademarks of SGS-THOMSON Microelectronics SGS-THOMSON Microelectronics GROUP OF COMPANIES Australia - Brazil - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands - Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A. M48T36 17/17 ...