M48T201V-70MH1TR STMICROELECTRONICS [STMicroelectronics], M48T201V-70MH1TR Datasheet
M48T201V-70MH1TR
Related parts for M48T201V-70MH1TR
M48T201V-70MH1TR Summary of contents
Page 1
... Watchdog timer ■ Choice of write protect voltages (V = Power-fail Deselect Voltage): PFD – M48T201Y 4.5 to 5.5V CC 4.1V V 4.5V PFD – M48T201V 3.0 to 3.6V CC 2.7V V 3.0V PFD ■ Microprocessor power-on reset (valid even during battery back-up mode.) ■ Programmable alarm output active in the battery backed-up mode ■ ...
Page 2
Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 3
List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 4
List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 5
... Do not place the SNAPHAT battery/crystal top in conductive foam as this will drain the lithium button-cell battery. Figure 1. Logic diagram and E signals. CON CON ® housing containing the battery and crystal. The A0-A18 WDI W M48T201Y M48T201V E G RSTIN1 RSTIN2 V SS ® Table 19 on page 33). DQ0-DQ7 IRQ/FT RST G CON E CON SQW V OUT AI02240 ...
Page 6
Table 1. Signal names A0-A18 DQ0-DQ7 RSTIN1 RSTIN2 RST WDI CON G CON IRQ/FT SQW V OUT 6/35 Address Inputs Data Inputs / Outputs Reset 1 Input Reset 2 Input Reset ...
Page 7
... OUT 3 42 SQW 4 41 IRQ/ A17 6 39 A15 7 38 A13 A11 M48T201Y M48T201V A10 CON 17 28 DQ7 18 27 DQ6 19 26 DQ5 20 25 DQ4 21 24 DQ3 AI02241 7/35 ...
Page 8
Figure 3. Hardware hookup 32,768 Hz CRYSTAL LITHIUM 5V CELL 0 the second chip enable pin (E2) is unused, it should be tied to V 8/35 A0-A18 V OUT 0.1 F M48T201Y ECON ...
Page 9
Operation Automatic backup and write protection for an external SRAM is provided through and G pins. (Users are urged to insure that voltage specifications, for both the CON CON SUPERVISOR chip and external SRAM chosen, are ...
Page 10
Table 2. Operating modes Mode Deselect 4.5V to 5.5V WRITE READ 3.0V to 3.6V READ Deselect V SO Deselect 1. See Table 14 on page 29 Note 2.2 Read mode ...
Page 11
Figure 5. Read cycle timing: RTC and external RAM control signals ADDRESS CON E CON tEPD W tGLQX DQ0-DQ7 READ READ tAVAV tAVAV tELQV tAVQV tELQX tGLQV tAXQX DATA OUT VALID WRITE tAVAV tAVWL tWHAX tRO tWLWH ...
Page 12
... Low or High Low CON High CON = 0 to 70° from Chip Enable or t from WRITE Enable prior to the initiation WHAX afterward. G should be kept high during WRITE Cycles to avoid WHDX after W falls. WLQZ M48T201V –70 –85 Max Min Max ...
Page 13
Figure 6. Write cycle timing: RTC and external RAM control signals ADDRESS tAVEL E tEPD E CON G tRO G CON tAVWL W tEHQZ DATA OUT DQ0-DQ7 VALID WRITE WRITE tAVAV tAVAV tAVEH tAVWH tELEH tEHAX tWHAX tEPD tEHDX tWLWH ...
Page 14
... This level is within 0.2V of the V CON remains at an out-of-tolerance condition. When power input is switched from the V BAT , become high impedance. The V OUT returns to a nominal value, write protection continues for 200ms (max) M48T201Y M48T201V –70 –85 Min Max Min Max ...
Page 15
Note: Most low power SRAMs on the market today can be used with the M48T201Y/V ® TIMEKEEPER SUPERVISOR. There are, however some criteria which should be used in making the final choice of an SRAM to use. The SRAM must ...
Page 16
Clock operation 3.1 TIMEKEEPER The M48T201Y/V offers 16 internal registers which contain TIMEKEEPER Watchdog, Flag, and Control data (see locations which contain external (user accessible) and internal copies of the data (usually referred to as BiPORT™ TIMEKEEPER cells). The ...
Page 17
Note not necessary to set the WRITE Bit when setting or resetting the FREQUENCY TEST Bit (FT) or the STOP Bit (ST). ® Table 5. TIMEKEEPER register map Address D7 D6 7FFFFh 10 Years 7FFFEh 0 0 7FFFDh ...
Page 18
Setting the alarm clock Registers 7FFF6h-7FFF2h contain the alarm settings. The alarm can be configured to go off at a prescribed time on a specific month, day of month, hour, minute, or second or repeat every month, day of ...
Page 19
Figure 8. Back-up mode alarm waveforms PFD (max) V PFD (min AFE bit/ABE bit AF bit in Flags Register IRQ/FT 3.6 Watchdog timer The watchdog timer can be used to detect an out-of-control microprocessor. The ...
Page 20
In order to perform a software reset of the watchdog timer, the original time-out period can be written into the Watchdog Register, effectively restarting the count-down cycle. Should the watchdog timer time-out, and the WDS Bit is programmed to output ...
Page 21
Power-on reset The M48T201Y/V continuously monitors V point, the RST pulls low (open drain) and remains low on power-up for t passes V (max). The RST pin is an open drain output and an appropriate pull-up resistor PFD to ...
Page 22
The oscillation rate of crystals changes with temperature (see M48T201Y/V design employs periodic counter correction. The calibration circuit adds or subtracts counts from the oscillator divider circuit at the divide by 256 stage, as shown in Figure 11 on page ...
Page 23
Figure 10. Crystal accuracy across temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 –30 –20 Figure 11. Calibration waveform NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION 3.11 Battery low warning The M48T201Y/V automatically performs battery voltage ...
Page 24
If a battery low indication is generated during the 24-hour interval check, this indicates that the battery is near end of life. However, data is not compromised due to the fact that a nominal V is supplied. In order to ...
Page 25
V noise and negative going transients CC I transients, including those produced by output switching, can produce voltage CC fluctuations, resulting in spikes on the V capacitors are used to store energy which stabilizes the V bypass capacitors will ...
Page 26
... Negative undershoots below –0.3V are not allowed on any pin while in the Battery Back-up mode. Caution: Do NOT wave solder SOIC to avoid damaging SNAPHAT sockets. 26/35 Parameter ® SNAPHAT SOIC –0 M48T201Y M48T201V Value Unit °C – °C –55 to 125 °C 260 ° ...
Page 27
... Input Rise and Fall Times Input Pulse Voltages Input and Output Timing Ref. Voltages Note: Output High Z is defined as the point where data is no longer driven. Figure 13. AC testing load circuit Note: Excluding open-drain output pin; 50pF for M48T201V. Table 12. Capacitance Symbol C Input Capacitance IN ...
Page 28
... OUT1 CC V > V –0.3 OUT2 BAT 4.1 4.35 3.0 3 70° 4.5 to 5.5V or 3.0 to 3.6V (except where noted through 100K resistor. WDI internally pulled-down specification. CC M48T201V –85 Max Min Typ Max ±1 ±1 ±1 ± 800 575 800 100 100 0.8 – ...
Page 29
... PFD SS tFB DON'T CARE HIGH-Z (1) Parameter Fall Time CC M48T201Y Fall Time M48T201V Rise Time CC Rise Time = 0 to 70° 4.5 to 5.5V or 3.0 to 3.6V (except where noted may result in deselection/write protection not occurring until 200µs after F may cause corruption of RAM data. FB ...
Page 30
Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. These packages have a Lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...
Page 31
Table 15. SOH44 – 44-lead plastic small outline, SNAPHAT, pack. mech. (continued) Symb Typ N CP Figure 16. SH – 4-pin SNAPHAT housing for 48mAh battery & crystal, package outline Note: Drawing is not to scale. Table 16. SH – ...
Page 32
Figure 17. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package outline Note: Drawing is not to scale. Table 17. SH – 4-pin SNAPHAT housing for 120mah battery & crystal, package mech. data Symb Typ ...
Page 33
... M48T Supply and write protect voltage 201Y = V = 4.5 to 5.5V 201V = V = 3.0 to 3.6V Speed –70 = 70ns (for M48T201Y) –85 = 85ns (for M48T201V) Package ( SOH44 Temperature range 70°C Shipping method for SOIC blank = Tubes TR = Tape & Reel 1. The SOIC package (SOH44) requires the battery package (SNAPHAT separately under the part number “ ...
Page 34
... M48T201, M48T201Y, M48T201V, 48T201, 48T201Y, 48T201V, T201, T201Y, T201V, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVI- SOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, SUPERVISOR, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIMEKEEPER, TIME- ...
Page 35
Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any ...