DS3234 Maxim, DS3234 Datasheet
DS3234
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DS3234 Summary of contents
Page 1
... The integra- tion of the crystal resonator enhances the long-term accu- racy of the device as well as reduces the piece-part count in a manufacturing line. The DS3234 is available in com- mercial and industrial temperature ranges, and is offered in an industry-standard 300-mil, 20-pin SO package. ...
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... For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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Extremely Accurate SPI Bus RTC with ELECTRICAL CHARACTERISTICS (continued 2.0V to 5.5V active supply (see Table 1 3.3V 3.0V, and T = +25°C, unless otherwise noted. TCXO operation guaranteed from 2.3V ...
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Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM AC ELECTRICAL CHARACTERISTICS (V = 2.0V to 5.5V -40°C to +85°C, unless otherwise noted.) (Note PARAMETER SYMBOL SCLK Clock Frequency Data to SCLK Setup SCLK ...
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Extremely Accurate SPI Bus RTC with RST PF(MAX) V PF(MIN) t VCCF RST WARNING: Negative undershoots below -0.3V while the part is in battery-backed mode may cause loss of data. Note 2: Limits at -40°C are guaranteed ...
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Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM CS t CCS t CC SCLK t t CDH t DC DIN W/R DOUT NOTE: SCLK CAN BE EITHER POLARITY, SHOWN FOR CPOL = SCLK t ...
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... SUPPLY VOLTAGE (V ) BAT AGING = -128 500 450 AGING = -33 400 AGING = 0 350 300 250 AGING = 32 200 DELTA TIME AND FREQUENCY vs. TEMPERATURE DS3234 toc06 20 0 CRYSTAL -20 +20ppm -40 TYPICAL CRYSTAL, -60 UNCOMPENSATED -80 -100 DS3234 CRYSTAL ACCURACY -120 -20ppm BAND -140 -160 -180 -200 ...
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... external pullup resistors should be connected. On first power-up the crystal CC is bypassed and RST immediately goes high. RST is not used, connect to ground. Diodes placed in series between the V BAT www.maxim-ic.com/qa/info/ul Pin Description relative to the CC , the RST exceeds V , for t CC ...
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... DECODE DIN DOUT Detailed Description The DS3234 is a TCXO and RTC with integrated crystal and 256 bytes of SRAM. An integrated sensor periodi- cally samples the temperature and adjusts the oscilla- tor load to compensate for crystal drift caused by temperature variations. The DS3234 provides user- selectable sample rates ...
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... DB If the line is still low, the DS3234 continuously monitors CC the line looking for a rising edge. Upon detecting falls below CC release, the DS3234 forces the RST pin low and holds it low for t RST , the BAT The same pin, RST, is used to indicate a power-fail ...
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... Integrated Crystal and SRAM The DS3234 operates as a slave device on the SPI seri- al bus. Access is obtained by selecting the part by the CS pin and clocking data into/out of the part using the SCLK and DIN/DOUT pins ...
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... Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM Figure 1. Address Map for DS3234 Timekeeping Registers and SRAM ADDRESS MSB BIT 6 READ/WRITE BIT 7 00h 80h 0 01h 81h 0 02h 82h 0 12/24 03h 83h 0 0 04h 84h 0 0 05h 85h Century 0 06h 86h ...
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... Extremely Accurate SPI Bus RTC with The DS3234 contains two time-of-day/date alarms. Alarm 1 can be set by writing to registers 07h to 0Ah. Alarm 2 can be set by writing to registers 0Bh to 0Dh. The alarms can be programmed (by the alarm enable and INTCN bits of the control register) to activate the INT/SQW output on an alarm match condition ...
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... Control Register (0Eh/8Eh) Bit 7: Enable Oscillator (EOSC). When set to logic 0, the oscillator is started. When set to logic 1, the oscilla- tor is stopped when the DS3234 switches to battery power. This bit is clear (logic 0) when power is first applied. When the DS3234 is powered by V oscillator is always on regardless of the status of the EOSC bit ...
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... When set to logic 0, the 32kHz pin is low. The initial power-up state of this bit is logic 1, and a 32.768kHz square-wave signal appears at the 32kHz pin after a power source is applied to the DS3234. This bit is enabled (logic 1) when power is first applied. Bit 2: Busy (BSY). This bit indicates the device is busy executing TCXO functions ...
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Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM BIT 7 BIT 6 NAME: SIGN DATA POR BIT 7 BIT 6 NAME: SIGN DATA POR BIT 7 BIT 6 NAME: DATA DATA POR ...
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... BIT The DS3234 provides a 4-wire SPI serial data bus to com- municate in systems with an SPI host controller. The DS3234 supports both single byte and multiple byte data transfers for maximum flexibility. The DIN and DOUT pins are the serial data input and output pins, respectively. ...
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Extremely Accurate SPI Bus RTC with Integrated Crystal and SRAM Address and data bytes are shifted MSB first into the serial data input (DIN) and out of the serial data output (DOUT). Any transfer requires the address of the byte ...
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... Data transfers can occur one byte at a time or in multi- ple-byte burst mode. After CS is driven low, an address is written to the DS3234. After the address, one or more data bytes can be written or read. For a single-byte transfer, one byte is read or written and then CS is dri- ven high ...
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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 draw- ings may show a different suffix character, but the drawing per- tains to the package regardless of RoHS status ...
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... Package Information table 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. ...