MAX6902ETA-T MAXIM [Maxim Integrated Products], MAX6902ETA-T Datasheet
MAX6902ETA-T
Related parts for MAX6902ETA-T
MAX6902ETA-T Summary of contents
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... Single-Byte or Multiple-Byte (Burst Mode) Data Transfer for Read or Write of Clock Registers or SRAM o Ultra-Small 8-Pin 3mm x 3mm x 0.8mm TDFN Package o Programmable Time/Date Polled ALARM Function Applications o No External Crystal Bias Resistors or Capacitors Required PART MAX6902ETA-T Related Real-Time Clock Products ALARM SRAM FUNCTION ✕ — 31 ✕ ...
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SPI-Compatible RTC in a TDFN ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V CC All Other Pins to GND ................................-0. Current into Any Pin..........................................................±20mA Rate of Rise, V ............................................................100V/µs CC Continuous Power Dissipation (T = +70°C) A ...
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AC ELECTRICAL CHARACTERISTICS (V = +2.0V to +5.5V -40°C to +85°C. Typical values are Notes 1, 4) PARAMETER SYMBOL OSCILLATOR X1 to Ground Capacitance X2 to Ground Capacitance SPI SERIAL TIMING Maximum Input Rise ...
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SPI-Compatible RTC in a TDFN (T = +25°C, unless otherwise noted.) A Pin Description PIN NAME FUNCTION Serial Clock Input. SPI clock for DIN and 1 SCLK DOUT data transfers. 2 DOUT SPI Data Output 3 DIN SPI Data Input ...
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REGISTER ADDRESS FUNCTION CLOCK SECONDS MINUTES HOURS DATE MONTH ...
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SPI-Compatible RTC in a TDFN REGISTER ADDRESS FUNCTION ALARM CONFIG /W RESERVED not write /W to this location. ALARM THRESHOLDS SECONDS ...
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REGISTER ADDRESS FUNCTION RAM RAM • • • • • • RAM RAM BURST Note: ...
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SPI-Compatible RTC in a TDFN Table 2. Register Address and Description (continued) WRITE (HEX) READ (HEX ...
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Command and Control Address/Command Byte Each data transfer into or out of the MAX6902 is initiated by an Address/Command byte. The Address/Command byte specifies which registers are to be accessed, and if the access is a read or a write. ...
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SPI-Compatible RTC in a TDFN unusable, and always read zero. Any data written to bits 0–6 are ignored. Bit 7 must be set to zero before a single write to the clock, before a write to RAM, or dur- ing ...
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Using the On-Board RAM The static RAM bits addressed consecutively in the RAM Address/Command space. Table 2 details the specific hex Address/Commands for Reads and Writes to each of the 31 locations of RAM. The contents ...
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SPI-Compatible RTC in a TDFN CS SCLK DIN ADDRESS/COMMAND BYTE** HIGH IMPEDANCE; NO ACTIVITY ON DOUT LINE DURING WRITES. DOUT * R = RAM/REGISTER SELECT BIT; RAM = 1, REGISTER = 0. ** ...
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CSS t CL SCLK DIN DOUT Figure 5. SPI Bus Timing Diagrams CS serves two functions. First, CS turns on the control logic that allows access to the Shift register ...
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SPI-Compatible RTC in a TDFN Table 3. 32.768kHz Surface-Mount Watch Crystals MANUFACTURER MANUFACTURER Abracon Corporation ABS25-32.768-12.5-B-2-T Caliber Electronics AWS2A-32.768KHz, AWS2B-32.768KHz ECS INC International ECS-.327-12.5-17 Fox Electronics FSM327 M-tron SX2010/ SX2020 Raltron RSE-32.768-12.5-C-T SaRonix 32S12A k = parabolic curvature constant (-0.035 ...
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Timekeeping Current When DOUT is high impedance (CS = high or during a DIN transfer segment), there is a potential for increased timekeeping current (up to 100x) if DOUT is allowed to float. If minimum timekeeping current is desired, then ...
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SPI-Compatible RTC in a TDFN GUARD RING * * * GROUND PLANE VIA CONNECTION Figure 7. MAX6902 Crystal PC Board Layout 16 ______________________________________________________________________________________ GROUND PLANE VIA CONNECTION * V PLANE 0.1µF CC VIA CONNECTION SM CAP * * * * ...
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SPI-Compatible RTC in a TDFN X1 OSCILLATOR DIVIDER 32.768kHz X2 VCC CONTROL LOGIC GND SCLK DIN INPUT SHIFT REGISTERS DOUT CS ALARM ALARM OUT CONTROL LOGIC ______________________________________________________________________________________ Functional Diagram 1Hz SECONDS MINUTES HOURS DATE MONTH DAY YEAR CONTROL ADDRESS REGISTER ...
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SPI-Compatible RTC in a TDFN (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages PIN 1 INDEX AREA COMMON DIMENSIONS SYMBOL MIN. A 0.70 ...