DS1685Q-5+ Maxim Integrated Products, DS1685Q-5+ Datasheet
DS1685Q-5+
Specifications of DS1685Q-5+
Related parts for DS1685Q-5+
DS1685Q-5+ Summary of contents
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... PDIP (0.600)/ SO (0.300)/ TSSOP (0.173) SQW V 22 BAUX RCLR AD0 AD1 BAT 6 DS1685Q AD2 IRQ 7 19 AD3 8 KS AD4 9 18 AD5 GND PLCC ALE DS1685/DS1687 3V/5V Real-Time Clocks RAM Clear Input ...
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... DS1685Q-3+ 0°C to +70°C DS1685Q-5+ 0°C to +70°C DS1685QN-3+ -40°C to +85°C DS1685QN-5+ -40°C to +85°C DS1685Q-3+T&R 0°C to +70°C DS1685Q-5+T&R 0°C to +70°C DS1685S-3+ 0°C to +70°C DS1685S-5+ 0°C to +70°C DS1685S-3+T&R 0°C to +70°C DS1685S-5+T&R 0°C to +70°C DS1687-3+ 0° ...
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DETAILED DESCRIPTION The DS1685/DS1687 are real-time clocks (RTC) designed as successors to the industry-standard DS1285, DS1385, DS1485, and DS1585 PC RTCs. These devices provide the industry-standard DS1285 clock function with either +3.0V or +5.0V operation. The DS1685 also incorporates a ...
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PIN DESCRIPTIONS PIN DS1685 DS1687 PDIP, SO, PLCC EDIP TSSOP 11, 13 16, — — — 5–10, 12, 4–11 4–11 14 12 ...
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PIN DESCRIPTIONS (continued) PIN DS1685 DS1687 PDIP, SO, PLCC EDIP TSSOP — NAME Kickstart Input, Active Low. When V DS1685/DS1687, ...
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Figure 1. Block Diagram X1 OSC X2 DS1687 only V CC GND V Power BAUX V Control BAT DS1687 only BUS W R Interface ALE AD0 - AD7 OSCILLATOR CIRCUIT The DS1685 uses an external 32.768kHz ...
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Table 1. Crystal Specifications* PARAMETER Nominal Frequency Series Resistance Load Capacitance * The crystal, traces, and crystal input pins should be isolated from RF generating signals. Refer to Application Note 58: Crystal Considerations for Dallas Real-Time Clocks for additional specifications. ...
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POWER-DOWN/POWER-UP CONSIDERATIONS The RTC function continues to operate, and all of the RAM, time, calendar, and alarm memory locations remain nonvolatile regardless of the level of the V and maximum limits whenever V point), the device becomes accessible after t ...
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The three time-alarm bytes can be used with the date alarm as described in the Wake-Up/Kickstart section. The century counter is discussed later in this text. ...
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Table 2. Time, Calendar, and Alarm Data Modes—Binary Mode ( ADDRESS BIT 7 BIT 6 00H 0 0 01H 0 0 02H 0 0 03H 0 0 AM/PM 04H 0 0 AM/PM 05H 0 0 06H 0 0 ...
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CONTROL REGISTERS The four control registers and D reside in both bank 0 and bank 1. These registers are accessible at all times, even during the update cycle. Register A (0Ah) MSB BIT 7 BIT 6 UIP ...
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Register B (0Bh) MSB BIT 7 BIT 6 BIT 5 SET PIE SET – When the SET bit the update transfer functions normally by advancing the counts once per second. When the SET bit is written to ...
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Register C (0Ch) MSB BIT 7 BIT 6 BIT 5 IQRF PF IRQF – The interrupt-request flag (IRQF) bit is set when one or more of the following are true PIE = ...
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NV RAM—RTC The 242 general-purpose NV RAM bytes are not dedicated to any special function within the DS1685/DS1687. They can be used by the application program as nonvolatile memory and are fully available during the update cycle. The user RAM ...
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SQUARE-WAVE OUTPUT SELECTION The SQW pin can be programmed to output a variety of frequencies divided down from the 32.768kHz crystal tied to X1 and X2. The square-wave output is enabled and disabled by the SQWE bit in Register B ...
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Table 3. Periodic Interrupt Rate and Square-Wave Output Frequency EXT. SELECT BITS REGISTER A REG B E32K RS3 RS2 ...
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Figure 4. Update-Ended And Periodic-Interrupt Relationship UIP UF PF EXTENDED FUNCTIONS The extended functions provided by the DS1685/DS1687 that are new to the RAMified RTC family are accessed by a software-controlled bank-switching scheme, as illustrated in Figure 5. In bank ...
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Figure 5. DS1685/DS1687 Register Map and Extended Register Bank Definition BANK 0 DV0 MSB = 0 00 TIMEKEEPING AND CONTROL BYTES-USER RAM 3F 64 BYTES-USER RAM 7F When bank 1 is selected, the clock/calendar registers and the ...
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SILICON SERIAL NUMBER A unique 64-bit lasered serial number is located in bank 1, registers 40h to 47h. This serial number is divided into three parts. The first byte in register 40h contains a model number, 47h, to identify the ...
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The timing associated with both the wake-up and kickstarting sequences is illustrated in the “Wake-Up/Kickstart Timing Diagram” in the Electrical Specifications section of this data sheet. The timing associated with these functions is divided into five intervals, labeled 1 to ...
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EXTENDED RAM The DS1685/DS1687 provides 128 on-chip SRAM, which is controlled as nonvolatile storage sustained by V and/ power-up, the RAM is accessible after T BAT BAUX The on-chip 128 x ...
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Extended Control Register 4B MSB BIT 7 BIT 6 ABE E32K ABE – Auxiliary Battery Enable. This bit when written to a logic 1 enables the V E32K – Enable 32.768kHz output. This bit when written to a logic 1 ...
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The RTC address is latched on the falling edge of the ALE signal. Each time an RTC address is latched, the register address stack is pushed. The stack is only four registers deep, holding the three previous RTC addresses in ...
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ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground………………………………………………………………….0.3V to +6V Operating Temperature Range, Commercial ...……………………………………………………………….0°C to +70°C Operating Temperature Range, Industrial…………………………………………………………………...-40C to +85C Storage Temperature Range EDIP………………………………....……………………………………………………………………….-40°C to +85°C PDIP, SO, TSSOP……………………………….…………………………………....………………….-55°C to +125°C Lead Temperature (soldering, ...
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DC ELECTRICAL CHARACTERISTICS (V = 5.0V±10 3.0V±10 PARAMETER (-5) Average V Power- CC Supply Current (-3) CMOS Standby (-5) Current - 0.2V) (-3) ( Input Leakage Current (Any Input) Output Leakage ...
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RTC AC TIMING CHARACTERISTICS (V = 3.0V±10 0°C to +70° PARAMETER Cycle Time Pulse Width, RD/WR Low Pulse Width, RD/WR High Input Rise and Fall Time Chip-Select Setup Time Before Chip-Select Hold ...
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RTC AC TIMING CHARACTERISTICS (V = 5.0V±10 0°C to +70° PARAMETER Cycle Time Pulse Width, RD/WR Low Pulse Width, RD/WR High Input Rise and Fall Time Chip-Select Setup Time Before Chip-Select Hold ...
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DS1685/DS1667 BUS TIMING FOR READ CYCLE TO RTC AND RTC REGISTERS DS1685/DS1687 BUS TIMING FOR WRITE CYCLE TO RTC AND RTC REGISTERS DS1685/DS1687 3V/5V Real-Time Clocks ...
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POWER-UP/DOWN TIMING— +25°C) A PARAMETER CS High to Power-Fail Recovery at Power-Up V Slew Rate Power-Down CC V Slew Rate Power-Down CC V Slew Rate Power-Up CC Expected Data Retention POWER-UP/DOWN TIMING— +25°C) A PARAMETER CS ...
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POWER-UP CONDITION—3V CS 2.6V 2. POWER FAIL POWER-DOWN CONDITION— POWER FAIL REC 2. 2.7V 2.6V 2. DS1685/DS1687 3V/5V Real-Time Clocks ...
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POWER-UP CONDITION—5V CS 4.5V 4.25V 4. POWER FAIL POWER-DOWN CONDITION— DS1685/DS1687 3V/5V Real-Time Clocks REC ...
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WAKE-UP/KICKSTART TIMING *THIS CONDITION CAN OCCUR WITH THE 3V DEVICE. NOTE: TIME INTERVALS SHOWN ABOVE ARE REFERENCED IN WAKE-UP/KICKSTART SECTION. Note 1: All voltages are referenced to ground. Note 2: Typical values are at +25°C and nominal supplies. Note 3: ...
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PACKAGE INFORMATION For the latest package outline information and land patterns www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time Maxim is a registered trademark of Maxim Integrated Products, Inc. The Dallas logo is a registered trademark of Maxim Integrated Products, Inc. DS1685/DS1687 3V/5V Real-Time Clocks DESCRIPTION © ...