DS1394 MAXIM [Maxim Integrated Products], DS1394 Datasheet
DS1394
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DS1394 Summary of contents
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... Maxim’s website at www.maxim-ic.com. ♦ Reset Output/Debounced Input (DS1391/DS1393) ♦ Separate SQW and INT Output (DS1392) ♦ Trickle-Charge Capability ♦ SPI Supports Modes 0 and 2 (DS1394) ♦ SPI Supports Modes 1 and 3 (DS1390/DS1391) ♦ 3-Wire Interface (DS1392/DS1393) ♦ 4MHz at 3.0V and 3.3V ♦ 1MHz at 1.8V ♦ ...
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... Input Leakage I/O Leakage RST Pin I/O Leakage I LORST DOUT Logic 1 Output I OHDOUT DOUT Logic 0 Output I OHDOUT Logic 0 Output (DS1390/DS1393/DS1394 I SQW/INT; DS1392 SQW, INT; DS1391/DS1393 RST) V Active Supply Current CC (Note 10) 2 _____________________________________________________________________ Storage Temperature Range .............................-55°C to +125°C Soldering Temperature...........................Refer to the IPC/JEDEC + 0 ...
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Low-Voltage SPI/3-Wire RTCs with RECOMMENDED DC OPERATING CONDITIONS (continued -40°C to +85°C, unless otherwise noted. Typical values are at nominal supply voltage and T CC CC(MIN) CC(MAX) A unless otherwise noted.) (Note ...
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Low-Voltage SPI/3-Wire RTCs with Trickle Charger SCLK CDH t DC W/R DIN DOUT CPHA = 1 NOTE: SCLK CAN BE EITHER POLARITY SHOWN FOR CPOL = 1. Figure 1a. Timing Diagram—SPI Read ...
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Low-Voltage SPI/3-Wire RTCs with CPHA = SCLK t CDH t DC DIN W/R WRITE ADDRESS BYTE DOUT NOTE: SCLK CAN BE EITHER POLARITY SHOWN FOR CPOL = 1. Figure 2a. Timing Diagram—SPI ...
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Low-Voltage SPI/3-Wire RTCs with Trickle Charger AC ELECTRICAL CHARACTERISTICS—3-WIRE INTERFACE ( -40°C to +85°C.) (Note 1) (Figures CC(MIN) CC(MAX) A PARAMETER SYMBOL SCLK Frequency (Note 13) f Data to SCLK ...
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Low-Voltage SPI/3-Wire RTCs with SCLK CDH t DC I/O A0 WRITE ADDRESS BYTE Figure 3. Timing Diagram—3-Wire Read Transfer SCLK CDH t DC I/O A0 WRITE ...
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Low-Voltage SPI/3-Wire RTCs with Trickle Charger POWER-UP/POWER-DOWN CHARACTERISTICS (T = -40°C to +85°C) (Figures PARAMETER SYMBOL V Detect to Recognize Inputs CC (V Rising Fall Time PF(MAX) V PF(MIN) V Rise Time; ...
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... CC BACKUP Note 6: Measured typ BACKUP SCLK, DIN DS1390/DS1391/DS1394; SCLK, and CE on DS1392/DS1393. Note 7: DOUT, SQW/INT (DS1390/DS1393/DS1394), SQW, and INT (DS1392). Note 8: Note 9: The RST pin has an internal 50kΩ (typ) pullup resistor to V Note 10: I —SCLK clocking at max frequency = 4MHz for 3V and 3.3V versions; 1MHz for 1.8V version; RST (DS1391/DS1393) CCA inactive ...
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Low-Voltage SPI/3-Wire RTCs with Trickle Charger (V = +3.3V +25°C, unless otherwise noted vs BBSQ1 = 0 BACKUP BACKUP 600 550 500 450 400 350 300 1.3 1.7 2.1 2.5 2.9 3.3 3.7 ...
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... Low-Voltage SPI/3-Wire RTCs with PIN DS1390/ DS1391 DS1392 DS1393 DS1394 — — — — — — — — 6 — — 9 — — — — — — ...
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... Address and data are transferred seri- ally through a 4-wire SPI interface for the DS1390 and DS1391 and through a 3-wire interface for the DS1392, DS1393, and DS1394. The DS1390/DS1391 operate as a slave device on the SPI serial bus. The DS1392/DS1393 operate using a 3-wire synchronous serial bus. Access is ...
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Low-Voltage SPI/3-Wire RTCs with Power Control The power-control function is provided by a precise, temperature-compensated voltage reference and a comparator circuit that monitors the V device is fully accessible and data can be written and read when V is greater ...
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... During a multibyte access, when the address pointer reaches 0Fh, it wraps around to location 00h. On the falling edge of the CS pin (DS1390/DS1391/DS1394) or the rising edge of CE (DS1392/DS1393), the current time is transferred to a second set of registers. The time information is read from these secondary registers, while the clock may continue to run ...
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Low-Voltage SPI/3-Wire RTCs with Table 3. Address Map (continued) WRITE READ BIT 7 BIT 6 ADDRESS ADDRESS 8Bh 0Bh AM3 12/24 8Ch 0Ch AM4 DY/DT 0 EOSC 8Dh 0Dh 0 0 8Eh 0Eh OSF 0 8Fh 0Fh TCS3 TCS2 Note: ...
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Low-Voltage SPI/3-Wire RTCs with Trickle Charger All five devices contain one time-of-day/date alarm. Writing to registers 88h through 8Ch sets the alarm. The alarm can be programmed (by the alarm enable and INTCN bits of the control register) to activate ...
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... Low-Voltage SPI/3-Wire RTCs with Special-Purpose Registers The DS1390–DS1394 have three additional registers (control, status, and trickle charger) that control the RTC, alarms, square-wave output, and trickle charger. BIT 7 BIT 6 BIT 5 EOSC 0 BBSQI Bit 7: Enable Oscillator (EOSC). When set to logic 0, this bit starts the oscillator ...
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... Low-Voltage SPI/3-Wire RTCs with Trickle Charger BIT 7 BIT 6 BIT 5 EOSC 0 BBSQI The INTCN bit used in the DS1390/DS1393/DS1394 becomes the SQW pin-enable bit in the DS1392. This BIT 7 BIT 6 BIT 5 OSF 0 Bit 7: Oscillator Stop Flag (OSF). A logic 1 in this bit indicates that the oscillator has stopped or was stopped for some time and may be used to judge the validity of the clock and calendar data ...
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... Low-Voltage SPI/3-Wire RTCs with TRICKLE-CHARGE REGISTER (8Fh WRITE, 0Fh READ) BIT 6 BIT 5 BIT 4 BIT 7 TCS3 TCS2 TCS1 TCS0 SELECT NOTE: ONLY 1010b ENABLES CHARGER V CC Figure 8. DS1390–DS1394 Programmable Trickle Charger Table 6. SPI Pin Function MODE CPHA Disable X Write 0 Read 0 Write 1 Read 1 * CPOL is the clock-polarity bit set in the control register of the host microprocessor ...
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... The DS1390/DS1391/DS1394 provide a 4-wire SPI seri- al-data bus to communicate in systems with an SPI host controller. The DS1390/DS1391 support SPI modes 1 and 3, while the DS1394 supports SPI modes 0 and 2. Both devices support 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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Low-Voltage SPI/3-Wire RTCs with CS SCLK (MODE 0) SCLK (MODE 1) DIN W DOUT Figure 10. SPI Single-Byte Write CS SCLK (MODE 0) SCLK (MODE 1) DIN W HIGH IMPEDANCE DOUT Figure 11. SPI ...
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Low-Voltage SPI/3-Wire RTCs with Trickle Charger CS SCLK DIN WRITE ADDRESS BYTE DIN ADDRESS BYTE READ DOUT HIGH-IMPEDANCE Figure 12. SPI Multiple-Byte Burst Transfer CE SCLK I Figure 13. 3-Wire Single-Byte Read CE SCLK I/O A1 ...
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Low-Voltage SPI/3-Wire RTCs with 3-Wire Serial-Data Bus The DS1392/DS1393 provide a 3-wire serial-data bus, and support both single-byte and multiple-byte data transfers for maximum flexibility. The I/O pin is the seri- al-data input/output pin. The CE input is used to ...
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... Low-Voltage SPI/3-Wire RTCs with Trickle Charger TOP VIEW DS1390 BACKUP DS1394 GND μSOP DS1392 V 3 BACKUP GND μSOP 24 ____________________________________________________________________ SQW/INT SCLK BACKUP 7 4 DOUT DIN GND ...
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... Low-Voltage SPI/3-Wire RTCs with CRYSTAL SCLK CPU DS1390/ DOUT DS1394 DIN GND CRYSTAL SCLK CPU DS1392 I/O GND For the latest package outline information and land patterns www.maxim-ic.com/packages. PACKAGE TYPE 10 µSOP SQW/INT ...
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... Added the “High Impedance” label for DOUT to Figure 1 and added DOUT trace to Figure 2. Changed all references of V Replaced the Operation section with the Power Control section and added new Table 1. Added the DS1394. 2 8/08 In the Address Map section, added the description on how to avoid misreads of the time registers ...