m48t512y STMicroelectronics, m48t512y Datasheet
m48t512y
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m48t512y Summary of contents
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... REAL TIME CLOCK, POWER-FAIL CONTROL CIRCUIT, BATTERY, AND CRYSTAL BCD CODED YEAR, MONTH, DAY, DATE, HOURS, MINUTES, AND SECONDS AUTOMATIC POWER-FAIL CHIP DESELECT and WRITE PROTECTION WRITE PROTECT VOLTAGES Power-fail Deselect Voltage) PFD – M48T512Y 4.5 to 5.5V CC 4.2V V 4.5V PFD – M48T512V 3.0 to 3. ...
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... M48T512Y, M48T512V* TABLE OF CONTENTS FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 1. 32-pin, PMDIP Module SUMMARY DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 2. Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Table 1. Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 3. 32-pin DIP Connections Figure 4. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 OPERATING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Table 2. Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 READ Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 5. READ Mode AC Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Table 3. READ Mode AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 WRITE Mode Figure 6 ...
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... PACKAGE MECHANICAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 13.PMDIP32 – 32-pin Plastic Module DIP, Package Outline . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 12. PMDIP32 – 32-pin Plastic Module DIP, Package Mechanical Data . . . . . . . . . . . . . . . . 18 PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 13. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 REVISION HISTORY Table 14. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 M48T512Y, M48T512V* 3/21 ...
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... V SS Figure 3. 32-pin DIP Connections 4/21 ® RAM is a The M48T512Y/V directly replaces industry stan- dard 512Kb x 8 SRAMs. It also provides the non- volatility of Flash without any requirement for spe- cial WRITE timing or limitations on the number of WRITEs that can be performed. Table 1. Signal Names ...
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... Figure 4. Block Diagram OSCILLATOR AND 32,768 Hz CRYSTAL LITHIUM CELL VOLTAGE SENSE CLOCK CHAIN POWER V PFD AND SWITCHING CIRCUITRY V CC M48T512Y, M48T512V TIMEKEEPER REGISTERS A0-A18 DQ0-DQ7 524,280 x 8 SRAM ARRAY AI02384 5/21 ...
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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 M48T512Y/V also has its own Power-Fail Detect circuit. This control circuitry constantly monitors the supply voltage for an out of tolerance condition ...
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... READ Mode The M48T512Y the READ Mode whenever W (WRITE Enable) is high and E (Chip Enable) is low. The unique address specified by the 19 Ad- dress Inputs defines which one of the 524,288 bytes of data accessed. Valid data will be available at the Data I/O pins within Address Ac- ...
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... M48T512Y, M48T512V* WRITE Mode The M48T512Y the WRITE Mode whenever W (WRITE Enable) and E (Chip Enable) are low state after the address inputs are stable. The start of a WRITE is referenced from the latter occurring falling edge WRITE is termi- nated by the earlier rising edge The ad- dresses must be held valid throughout the cycle ...
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... If E goes low simultaneously with W going low, the outputs remain in the high impedance state. M48T512Y (1) -70 Min Max 70° 4.5 to 5.5V or 3.0 to 3.6V (except where noted M48T512Y, M48T512V* M48T512V -85 Min Max Unit ns ns ...
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... The internal energy source will PFD maintain data in the M48T512Y/V for an accumu- lated period of at least 10 years at room tempera- ture. As system power rises above V battery is disconnected, and the power supply is ...
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... Bit D7 within 7FFF9h. Setting '1' stops the oscillator. The M48T512Y/V is shipped from STMicroelectronics with the STOP bit set to a '1.' When reset to a '0,' the M48T512Y/ V oscillator starts after approximately 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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... M48T512Y, M48T512V* Calibrating the Clock The M48T512Y/V is driven by a quartz controlled oscillator with a nominal frequency of 32,768Hz. The devices are factory calibrated at 25°C and tested for accuracy. Clock accuracy will not ex- ceed 35 ppm (parts per million) oscillator frequen- cy error at 25°C, which equates to about ±1.53 minutes per month ...
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... ST recommends connecting a schottky diode from nected anode 1N5817 is recommended for through hole and MBRS120T3 is recommended for surface mount). Figure 10. Supply Voltage Protection bus. The energy (cathode con (Schottky diode M48T512Y, M48T512V* AI00594B 0.1 F DEVICE V SS AI02169 13/21 ...
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... M48T512Y, M48T512V* 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 6 ...
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... IN (3) Input / Output Capacitance C IO Note: 1. Effective capacitance measured with power supply at 5V (M48T512Y) or 3.3V (M48T512V). Sampled only, not 100% tested 25° 1MHz. 3. Outputs deselected. ment 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 ...
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... M48T512Y, M48T512V* Table 9. DC Characteristics Symbol Parameter I Input Leakage Current LI (2) Output Leakage Current Supply Current CC I Supply Current (Standby) TTL CC1 Supply Current (Standby) I CC2 CMOS V Input Low Voltage IL V Input High Voltage IH V Output Low Voltage OL V Output High Voltage OH Note: 1 ...
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... V F may cause corruption of RAM data. FB (1,2) M48T512Y M48T512V M48T512Y M48T512V . = 0 to 70° 4.5 to 5.5V or 3.0 to 3.6V (except where noted M48T512Y, M48T512V* tR tRB tREC DON'T CARE RECOGNIZED HIGH-Z VALID Min Max 300 10 150 10 ...
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... M48T512Y, M48T512V* PACKAGE MECHANICAL INFORMATION Figure 13. PMDIP32 – 32-pin Plastic Module DIP, Package Outline Note: Drawing is not to scale. Table 12. PMDIP32 – 32-pin Plastic Module DIP, Package Mechanical Data Symb Typ 18/ ...
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... Package PM = PMDIP32 Temperature Range 70°C Note: 1. Contact local ST sales office for availability of 3.3V version. For other options, or for more information on any aspect of this device, please contact the ST Sales Office nearest you. M48T = 2.7 to 3.0V M48T512Y, M48T512V* 512Y – 19/21 ...
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... M48T512Y, M48T512V* REVISION HISTORY Table 14. Document Revision History Date Version June 1998 1.0 First Issue M48T512Y: V 03-Dec-99 1.1 and t RB 11-Dec-00 2.0 Reformatted 20-Jul-01 2.1 Segments re-ordered; temp./voltage info. added to tables (Table 10, 11) 07-Aug-01 2.2 Text re-ordered from last adjustment (“Operating Modes” section) 20-May-02 2 ...
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