DS1511 Maxim, DS1511 Datasheet
DS1511
Available stocks
Related parts for DS1511
DS1511 Summary of contents
Page 1
... Y2K-Compliant Watchdog Real-Time Clocks GENERAL DESCRIPTION The DS1501/DS1511 are full-function, year 2000- compliant real-time clock/calendars (RTCs) with an RTC alarm, watchdog timer, power-on reset, battery monitors, 256 bytes NV SRAM, and a 32.768kHz output. User access to all registers within the DS1501/DS1511 is accomplished with a byte-wide interface, as shown in Figure 8 ...
Page 2
... Operating Temperature Range, DS1501 Operating Temperature Range, DS1511……………………………………………………………….……..0°C to +70°C Storage Temperature Range, DS1501 Storage Temperature Range, DS1511… ...
Page 3
... WE Pulse Width CE Pulse Width Data Setup Time Data Hold Time Address Hold Time WE Data-Off Time Write Recovery Time Pulse Width, OE, WE High Pulse Width, OE, WE Low DS1501/DS1511 Y2KC Watchdog Real-Time Clocks = 0V -40°C to +85°C.) A SYMBOL CONDITIONS I (Note 7) BAT1 ...
Page 4
... Data Hold Time Address Hold Time WE Data-Off Time Write Recovery Time Pulse Width, OE, WE High Pulse Width, OE, WE Low Figure 1. Read Cycle Timing A0– DQ0-DQ7 DS1501/DS1511 Y2KC Watchdog Real-Time Clocks = 3.3V ±10 -40°C to +85°C SYMBOL CONDITIONS ...
Page 5
... Figure 2. Write Cycle Timing, Write-Enable Controlled A0– DQ0–DQ7 Figure 3. Write Cycle Timing, Chip-Enable Controlled A0- DQ0-DQ7 DS1501/DS1511 Y2KC Watchdog Real-Time Clocks t WC VALID WEW WEZ DH DATA OUTPUT DATA INPUT VALID DATA INPUT ...
Page 6
... On) CAPACITANCE (T = +25°C) A PARAMETER Capacitance on All Input Pins Capacitance on IRQ, PWR, RST, and DQ Pins AC TEST CONDITIONS OUTPUT LOAD (Y) 50pF + 1TTL Gate (W) 25pF + 1 TTL Gate DS1501/DS1511 Y2KC Watchdog Real-Time Clocks SYMBOL CONDITIONS ...
Page 7
... Figure 5. 3.3V Power-Up/Down Waveform Timing Figure 6. 5V Power-Up/Down Waveform Timing Warning: Under no circumstances are negative undershoots, of any amplitude, allowed when device is in battery-backup mode. DS1501/DS1511 Y2KC Watchdog Real-Time Clocks ...
Page 8
... Note 8: These parameters are sampled with a 5pF load and are not 100% tested. Note the amount of time that the internal battery can power the internal oscillator and internal registers of the DS1511. DR Note 10: If the oscillator is not enabled, the startup time of the oscillator after V Note 11: Typical values are at +25° ...
Page 9
... DS1501/DS1511 Y2KC Watchdog Real-Time Clocks NAME Active-Low Power-On Output (Open Drain). This output, if used, is normally PWR connected to power-supply control circuitry. This pin requires a pullup resistor connected to a positive supply to operate correctly. Connections for Standard 32.768kHz Quartz Crystal. For greatest accuracy, the DS1501 must be used with a crystal that has a specified load capacitance of either 6pF or 12 ...
Page 10
... V BAT POWER CONTROL V BAUX WRITE PROTECTION, AND POWER-ON GND RESET KS Figure 9. Typical Crystal Layout LOCAL GROUND PLANE (LAYER 2) CRYSTAL DS1501/DS1511 Y2KC Watchdog Real-Time Clocks CLOCK ALARM AND WATCHDOG COUNTDOWN DS1501/DS1511 X1 X2 GND IRQ SQW CLOCK AND CONTROL REGISTERS A0–A4 DQ0– ...
Page 11
... DATA WRITE MODE The DS1501/DS1511 are in write mode whenever CE and WE are in their active state. The start of a write is referenced to the latter occurring transition WE. The addresses must be held valid throughout the cycle. ...
Page 12
... BAUX OSCILLATOR CONTROL BIT When the DS1511 is shipped from the factory, the internal oscillator is turned off. This feature prevents the lithium energy cell from being used until it is installed in a system. The oscillator is automatically enabled when power is first applied. ...
Page 13
... An external 32.768kHz oscillator can also drive the DS1501. When using an external oscillator the X2 pin must be left open. The DS1511 contains an embedded crystal and is factory trimmed to be better than ±1 ° min/month at +25 C ...
Page 14
... The alarm can be programmed to activate on a specific day of the month, day of the week, or repeat every day, hour, minute, or second. It can also be programmed to go off while the DS1501/DS1511 are in the battery-backed state of operation to serve as a system wakeup. Alarm mask bits AM1 to AM4 control the alarm mode. Table 3 shows the possible settings ...
Page 15
... RAM memory or clock functions. These bits are read only. PRS, Reset Select Bit (0Eh Bit 5) When set to 0, the PWR pin is set high-Z when the DS150/DS1511 go into power-fail. When set to 1, the PWR pin remains active upon entering power-fail. ...
Page 16
... CS, Crystal Select Bit (0Fh Bit 6) When CS is set to 0, the oscillator is configured for operation with a crystal that has a 6pF specified load capacitance. When the oscillator is configured for a 12.5pF crystal disabled in the DS1511 module and should be set BME, Burst-Mode Enable Bit (0Fh Bit 5) The burst-mode enable bit allows the extended user RAM address registers to automatically increment for consecutive reads and writes. When BME is set to 1, the automatic incrementing is enabled ...
Page 17
... WDE = 1 and WDS = 1: WDF is set, the RST pin pulses low, and WDE resets to 0. WAKEUP/KICKSTART The DS1501/DS1511 incorporate a wakeup feature, which powers predetermined day/date and time by activating the PWR output pin. Additionally, the kickstart feature allows the system to be powered up in response to a low-going transition on the KS pin, without operating voltage applied to the V can be applied upon such events as key closure or a modem-ring-detect signal ...
Page 18
... TDF and/or KSF by reading the flags register or by writing TDF and KSF long as no other interrupt within the DS1501/DS1511 is pending, the IRQ line is taken inactive once these bits are reset, and execution of the application software can proceed. During this time, the wakeup and kickstart functions can be used to generate status and interrupts ...
Page 19
... DS1511W+ 3.3 DS1511Y+ 5.0 +Denotes a lead(Pb)-free/RoHS-compliant package “+” anywhere on the top mark denotes a lead(Pb)-free package IND denotes an industrial temperature device. DS1501/DS1511 Y2KC Watchdog Real-Time Clocks TEMP RANGE PIN-PACKAGE 28 DIP (0.600) -40C to +85 (0.300) 0C to +70 (0.300) -40 ...
Page 20
... IRQ 5 24 DS1501 DQ0 11 18 DQ1 12 17 DQ2 13 16 GND 14 15 DIP, SO DS1501/DS1511 Y2KC Watchdog Real-Time Clocks SQW 2 BAUX BAT V 4 BAT BAUX SQW PWR 8 GND X1 ...
Page 21
... DQ0–DQ7 PACKAGE INFORMATION For the latest package outline information and land patterns www.maxim-ic.com/packages. PACKAGE TYPE 28-pin DIP (600 mils) 28-pin SO (300 mils) 28-pin TSOP (8mm x 13.4mm) 28-pin EDIP (720 mils) DS1501/DS1511 Y2KC Watchdog Real-Time Clocks V CC CRYSTAL ...
Page 22
... © 2009 Maxim Integrated Products DS1501/DS1511 Y2KC Watchdog Real-Time Clocks DESCRIPTION ...