m41st95y STMicroelectronics, m41st95y Datasheet
m41st95y
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m41st95y Summary of contents
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... FEATURES SUMMARY 5.0 OR 3.0V OPERATING VOLTAGE SERIAL PERIPHERAL INTERFACE (SPI) NVRAM SUPERVISOR FOR EXTERNAL LPSRAM 2.5 TO 5.5V OSCILLATOR OPERATING VOLTAGE AUTOMATIC SWITCH-OVER AND DESELECT CIRCUITRY CHOICE OF POWER-FAIL DESELECT VOLTAGES: – M41ST95Y 4.5 to 5.5V CC 4.20V V 4.50V PFD – M41ST95W 2.7 to 3.6V CC 2.55V V 24.70V PFD 1.25V REFERENCE (FOR PFI/PFO) ...
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... M41ST95Y*, M41ST95W TABLE OF CONTENTS FEATURES SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 1. 28-pin SOIC Package Figure 2. 28-pin (300mil) SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 SUMMARY DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 3. Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Table 1. Signal Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Figure 4. 28-pin SOIC Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 5. 28-pin, 300mil SOIC (MX) Connections Figure 6. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 7. Hardware Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 SPI Bus Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Signal Description ...
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... Figure 25.SOX28 – 28-lead Plastic Small Outline, 300mils, Embedded Crystal, Outline . . . . . . . . 32 Table 18. SOX28 – 28-lead Plastic Small, 300mils, Embedded Crystal, Package Mech. Data . . . 32 PART NUMBERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 19. Ordering Information Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 20. SNAPHAT Battery Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 REVISION HISTORY Table 21. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 M41ST95Y*, M41ST95W 3/35 ...
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... BCD format. Corrections for 28, 29 (leap year - valid until year 2100), 30 and 31 day months are made automatically. 4/35 ® SRAM The M41ST95Y/W is supplied in a 28-lead SOIC ® SNAPHAT crystal and battery in a single SNAPHAT top 28-pin, 300mil SOIC package (MX) which includes 16) are used for an embedded 32kHz crystal ...
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... BAT Note: 1. For SOX28 package only. 2. Available only in 28-pin, 300mil SOIC (MX) package. M41ST95Y*, M41ST95W Conditioned Chip Enable Output External Chip Enable Chip Enable Interrupt/Frequency Test/Out Output (Open Drain) Reset Output (Open Drain) Reset 1 Input Reset 2 Input Serial Clock Input ...
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... M41ST95Y*, M41ST95W Figure 4. 28-pin SOIC Connections SQW M41ST95Y 22 M41ST95W WDI 8 21 RSTIN1 9 20 RSTIN2 PFO 6/35 Figure 5. 28-pin, 300mil SOIC (MX) Connections (1) NF IRQ/FT/OUT ...
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... REAL TIME CLOCK CALENDAR 44 BYTES USER RAM RTC w/ALARM & CALIBRATION OUTPUT DRIVER FREQUENCY TEST WATCHDOG SQUARE WAVE COMPARE V BL COMPARE V SO POR V COMPARE PFD COMPARE M41ST95Y*, M41ST95W AFE OUT FT (1) IRQ/FT/OUT WDS SQW (2) F 32k V OUT BL (1) RST E CON PFO AI06371 7/35 ...
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... M41ST95Y*, M41ST95W Figure 7. Hardware Hookup D SPI Interface with (CPOL, CPHA) ( ('0','0') or ('1','1') C Master (ST6, ST7, ST9, ST10, Others) CS3 CS2 CS1 Note: 1. CPOL (Clock Polarity) and CPHA (Clock Phase) are bits that may be set in the SPI Control Register of the MCU. ...
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... The SCL input, which is generated by the micro- controller, is active only during address and data transfer to any device on the SPI bus (see 7., page 8). The M41ST95Y/W can be driven by a microcon- troller with its SPI peripheral running in either of the two following modes: (CPOL, CPHA) = ('0', '0') or (CPOL, CPHA) = ('1', '1'). ...
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... SCL SDI SDO 10/35 The M41ST95Y/W can be driven by a microcon- troller with its SPI peripheral running in either of the two following modes: (CPOL, CPHA) = ('0', '0') or (CPOL, CPHA) = ('1', '1'). For these two modes, input data (SDI) is latched in by the low-to-high transition of clock SCL, and out- ...
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... MSB OUT SDO ADDR. LSB IN SDI Figure 11. WRITE Cycle Timing: RTC and External SRAM Control Signals EX tEXPD E CON tELCH tCHEH tCHDX tCLCH LSB IN tDLDH tDHDL tCH tEXPD M41ST95Y*, M41ST95W tEHEL tEHCH tCHCL AI04633 tCL tEHQZ LSB OUT tQLQH tQHQL AI04634 AI03663 11/35 ...
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... M41ST95Y*, M41ST95W Table 3. AC Characteristics Symbol f Serial Clock Input Frequency SCL (2) Clock High t CH (3) Clock Transition (Fall Time) t CHCL t Serial Clock Input High to Input Data Transition CHDX t Serial Clock Input High to Chip Enable High CHEH (2) Clock Low t CL (3) Clock Transition (Rise Time) ...
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... RAM address (08h to 3Fh). Note: This is true both in READ and WRITE mode DATA OUT (BYTE MSB M41ST95Y*, M41ST95W 22 DATA OUT (BYTE MSB AI04635 13/35 ...
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... The RST signal also re- REC CON mains active during this time (see 21., page 28). Note: Most low power SRAMs on the market to- day can be used with the M41ST95Y/W RTC SU- PERVISOR. There are, however some criteria which should be used in making the final choice of an SRAM to use. 14/ ...
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... TIMEKEEPER Registers The M41ST95Y/W offers 20 internal registers which contain Clock, Alarm, Watchdog, Flag, Square Wave and Control data (see 4., page 16). These registers are memory loca- tions which contain external (user accessible) and internal copies of the data (usually referred to as ™ ...
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... M41ST95Y*, M41ST95W ® Table 4. TIMEKEEPER Register Map Addr 00h 0.1 Seconds 01h ST 10 Seconds 02h 0 10 Minutes 03h CEB CB 10 Hours 04h 05h Date 06h 07h 10 Years 08h OUT FT S 09h WDS BMB4 BMB3 0Ah AFE SQWE ABE ...
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... It can also be pro- grammed to go off while the M41ST95Y the battery back-up to serve as a system wake-up call. Bits RPT5-RPT1 put the alarm in the repeat mode of operation ...
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... The ABE and AFE Bits are reset during power-up, therefore an alarm generated during power-up will only set AF. The user can read the Flag Register at system boot-up to determine if an alarm was generated while the M41ST95Y/W was in the de- select mode during power-up. illustrates the back-up mode alarm timing. 0Fh ...
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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 M41ST95Y/W sets the WDF (Watchdog Flag) and generates a watchdog inter- rupt or a microprocessor reset. WDF is reset by reading the Flags Register (0Fh). ...
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... Full-time F Square Wave Output 32k (Available only in 28-pin, 300mil SOIC (MX) package). The M41ST95Y/W offers the user a special 32kHz square wave function which is always output on the F pin (Pin 21) as long as V 32k CC oscillator is running (ST Bit = '0'). This function is available within four seconds of initial power-up ...
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... Programmable (see Table 8., page 5. After crystal oscillator has started Reset Input (RSTIN1 and RSTIN2) . The M41ST95Y/W provides two independent in- CC puts which can generate an output reset. The du- ration and function of these resets is identical to a (max). reset generated by a power cycle. Table ...
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... DC input ( available) or the regulated output of the V CC voltage divider can be set up such that the voltage at PFI falls below V several milliseconds before PFI the regulated V input to the M41ST95Y/W or the CC microprocessor drops below the minimum operat- ing voltage. Figure 17. Power-Fail Comparator Hookup Regulator Unregulated V ...
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... In order to insure data integrity during subsequent periods of battery back-up mode, the battery should be replaced. The SNAPHAT may be replaced while V The M41ST95Y/W only monitors the battery when a nominal V cations which require extensive durations in the battery back-up mode should be powered-up peri- odically (at least once every few months) in order for this technique to be beneficial ...
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... M41ST95Y*, M41ST95W Figure 18. Crystal Accuracy Across Temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 –30 –20 Figure 19. Calibration Waveform NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION 24/ – –0.036 ppm/ C ± 0.006 ppm ± ...
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... STMicroelectronics SURE Program and other rel- evant quality documents. Parameter Off, Oscillator Off) CC M41ST95Y M41ST95W Lead-free lead finish Standard (SnPb) lead finish M41ST95Y*, M41ST95W Refer also to the Value Unit –55 to 125 °C –0 –0.3 to 4.6 V ...
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... M41ST95Y*, M41ST95W DC AND AC PARAMETERS This section summarizes the operating and mea- surement conditions, as well as the DC and AC characteristics of the device. The parameters in the following DC and AC Characteristic tables are derived from tests performed under the Measure- Table 11. DC and AC Measurement Conditions Parameter V Supply Voltage ...
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... PFI Rising 20 70 2.5 = –40 to 85° 4.5 to 5.5V or 2.7 to 3.6V (except where noted through 100K resistor. WDI internally pulled-down specification this supply must be equal to, or less than 3.0V when CC M41ST95Y*, M41ST95W M41ST95W Min Typ Max 400 550 1.4 ±1 – ±1 ...
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... M41ST95Y*, M41ST95W Figure 21. Power Down/Up Mode AC Waveforms PFD (max) V PFD (min tPD PFO INPUTS RECOGNIZED RST OUTPUTS VALID (PER CONTROL INPUT) E CON Table 14. Power Down/Up AC Characteristics Symbol Parameter (2) V (max (min PFD PFD F (3) V (min PFD ...
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... Min Max Typ 3.05 0.05 0.36 2.34 2.69 0.36 0.51 0.15 0.32 17.71 18.49 8.23 8.89 – – 0.050 3.20 3.61 11.51 12.70 0.41 1.27 0° 8° 28 0.10 M41ST95Y*, M41ST95W C L inches Min Max 0.120 0.002 0.014 0.092 0.106 0.014 0.020 0.006 0.012 0.697 0.728 0.324 0.350 – – 0.126 0.142 0.453 0.500 0.016 0.050 0° 8° 28 0.004 29/35 ...
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... M41ST95Y*, M41ST95W Figure 23. SH – 4-pin SNAPHAT Housing for 48mAh Battery & Crystal, Package Outline Note: Drawing is not to scale. Table 16. SH – 4-pin SNAPHAT Housing for 48mAh Battery & Crystal, Package Mechanical Data millimeters Symbol Typ 30/35 A1 ...
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... Table 17. SH – 4-pin SNAPHAT Housing for 120mAh Battery & Crystal, Package Mech. Data millimeters Symbol Typ Min Max Typ 10.54 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 M41ST95Y*, M41ST95W SHTK-A inches Min Max 0.4150 0.2650 0.2850 0.2551 0.2752 0.0150 0.0181 0.0220 0.8350 0.8598 0.5598 0.5902 0.6122 0.6280 0.1260 0.1421 0.0799 0.0902 31/35 ...
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... M41ST95Y*, M41ST95W Figure 25. SOX28 – 28-lead Plastic Small Outline, 300mils, Embedded Crystal, Outline SO-E Note: Drawing is not to scale. Table 18. SOX28 – 28-lead Plastic Small, 300mils, Embedded Crystal, Package Mech. Data millimeters Symbol Typ ddd ...
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... Lithium Battery (48mAh) and Crystal SNAPHAT M4T32-BR12SH Lithium Battery (120mAh) and Crystal SNAPHAT M41ST 95Y 4.50V PFD 2.70V ® ), Tubes ® ), Tape & Reel ® battery package which is ordered separately under the part number “M4TXX- Description M41ST95Y*, M41ST95W MH 6 Package SH SH 33/35 ...
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... Update Maximum ratings (Table 10) M41ST95, 41ST95, ST95, M41ST95Y, 41ST95Y, ST95Y, M41ST95W, 41ST95W, ST95W, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, Serial, ...
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