M48T128 ST Microelectronics, M48T128 Datasheet
M48T128
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M48T128 Summary of contents
Page 1
... 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 (V = Power-fail Deselect Voltage): PFD – M48T128Y: 4.1V V PFD – M48T128V: 2.7V V PFD CONVENTIONAL SRAM OPERATION; UNLIMITED WRITE CYCLES SOFTWARE CONTROLLED CLOCK ...
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... E counters, they are memory locations consisting of 21 DQ7 BiPORT™ read/write memory cells within the stat- 20 DQ6 ic RAM array. The M48T128Y/V includes a clock 19 DQ5 control circuit which updates the clock bytes with current information once per second. The informa- 18 DQ4 tion can be accessed by the user in the same man- ...
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... Data Hold Time) but will go indeterminate until the next Address Access. WRITE MODE The M48T128Y 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 ...
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... the internal battery, preserving data and pow- ering the clock. The internal energy source will maintain data in the M48T128Y/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 switched to external V ...
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... Supply Current (Standby) TTL CC1 I Supply Current (Standby) CMOS CC2 Input Low Voltage Input High Voltage IH V Output Low Voltage OL V Output High Voltage OH Note: 1. Outputs deselected. M48T128Y, M48T128V Test Condition Min OUT Test Condition Min ...
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... M48T128Y, M48T128V Figure 5. Power Down/Up Mode AC Waveforms PFD (max) V PFD (min INPUTS RECOGNIZED OUTPUTS VALID Table 7. Power Down/Up Trip Points DC Characteristics ( °C) A Symbol V Power-fail Deselect Voltage PFD V Battery Back-up Switchover Voltage SO (2) Expected Data Retention Time t DR Note: 1 ...
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... Note 100pF or 50pF (See Figure 3 5pF. L Figure 6. Address Controlled, Read Mode AC Waveforms A0-A16 DQ0-DQ7 DATA VALID M48T128Y -70 Min tAVAV VALID tAVQV tAXQX M48T128Y, M48T128V M48T128V -85 Max Min Max DATA VALID ...
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... The STOP bit is located at Bit D7 within 1FFF9h. Setting '1' stops the oscillator. The M48T128Y/V is shipped from STMicroelectronics with the STOP bit set to a '1'. When reset to a '0', the M48T128Y/ V oscillator starts after one second. -85 Unit Max ...
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... A0-A16 E G DQ0-DQ7 Figure 8. Write Enable Controlled, Write AC Waveforms A0-A16 E W DQ0-DQ7 tAVAV VALID tAVQV tELQV tELQX tGLQV tGLQX tAVAV VALID tAVWH tAVEL tWLWH tAVWL tWLQZ tDVWH M48T128Y, M48T128V tAXQX tEHQZ tGHQZ DATA OUT AI01197 tWHAX tWHQX tWHDX DATA INPUT AI02382 9/14 ...
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... A0-A16 E W DQ0-DQ7 CALIBRATING THE CLOCK The M48T128Y/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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... CC while in battery backup mode. To protect from these voltage spikes, ST recommends connecting bus. The CC a schottky diode from V nected to V 1N5817 is recommended for through hole and MBRS120T3 is recommended for surface mount). M48T128Y, M48T128V Function/Range BCD Format D1 D0 Year Month Date Day Day ...
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... M48T128Y, M48T128V Table 12. Ordering Information Scheme Example: Device Type M48T Supply Voltage and Write Protect Voltage 4.5V to 5.5V 4.1V to 4.5V CC PFD 3.0V to 3.6V 2.7V to 3.0V CC PFD Speed -70 = 70ns -85 = 85ns Package PM = PMDIP32 Temperature Range °C For a list of available options (Speed, Package, etc...) or for further information on any aspect of this de- vice, please contact the ST Sales Office nearest to you ...
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... N 1 Drawing is not to scale. mm Min Max 9.27 9.52 0.38 – 0.43 0.59 0.20 0.33 42.42 43.18 18.03 18.80 2.29 2.79 34.29 41.91 14.99 16.00 3.05 3.81 1.91 2. M48T128Y, M48T128V inches Typ Min Max 0.365 0.375 0.015 0.017 0.023 0.008 0.013 1.670 1.700 0.710 0.740 0.090 0.110 1.350 1.650 0.590 0.630 0.120 0.150 0.075 0.110 PMDIP – 13/14 ...
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... M48T128Y, M48T128V Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice ...