s-35392a Seiko Instruments Inc., s-35392a Datasheet
s-35392a
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s-35392a Summary of contents
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... REAL-TIME CLOCK The S-35392A is a CMOS 2-wire real-time clock IC which operates with the very low current consumption and in the wide range of operation voltage. The operation voltage that this IC can be used for various power supplies from main supply to backup battery. ...
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... VDD Pin for positive power supply 2 SNT-8A Top view 8 32KO XOUT XIN VSS Figure 1 Pin Configuration (S-35392A-I8T1G) Table 1 Description I/O Output − − Output Input Bi-directional − Seiko Instruments Inc. VDD SDA SCL INT2 Configuration Nch open-drain output (no protective diode at VDD) − ...
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... Figure 2 SDA Pin 2 C-bus interface. This pin inputs/outputs data by synchronizing with a clock pulse 2 C-bus interface. The SDA pin inputs/outputs data by synchronizing with the clock SCL 32KO, INT2 Figure 4 32KO Pin, INT 2 Pin Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK S-35392A Figure 3 SCL Pin 3 ...
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... REAL-TIME CLOCK S-35392A Block Diagram XIN Oscillator XOUT Clock correction register Status register 1 Status register 2 Free register Low power supply VDD voltage detector Power-on detector Constant- voltage circuit VSS 4 Divider, timing generator INT1 register Comparator 1 Second Minute Hour INT2 register ...
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... Conditions V Within 10 seconds STA t − STA δIC − δ 1 Applied to XIN pin g C Applied to XOUT pin d Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK S-35392A Rating V − − − −40 to +85 −55 to +125 Min. Typ. ...
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... REAL-TIME CLOCK S-35392A DC Electrical Characteristics (Ta = −40 to +85°C, V Parameter Symbol Current consumption 1 I DD1 Current consumption 2 I DD2 Input current leakage 1 I IZH Input current leakage 2 I IZL Output current leakage 1 I OZH Output current leakage 2 I OZL Input voltage 1 ...
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... R t SU.STO t SU.DAT S-35392A Unit Max. 400 kHz − µs µs − µs 0.9 µs − µs − − ns µs − − µs µs 0.3 µs 0.3 − ...
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... Configuration of Data Communication 1. Configuration of data communication For data communication, the master device in the system generates a start condition for the S-35392A. Next, the master device transmits 4-bit device code “0110”, 3-bit command and 1-bit Read/Write command to the SDA bus. After that, output or input is performed from B7 of data ...
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... Rev.1.3 _00 2. Configuration of command 8 types of command are available for the S-35392A, The S-35392A does Read/Write the various registers by inputting these fixed codes and commands. The S-35392A does not perform any operation with any codes and commands other than those below. Device ...
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... REAL-TIME CLOCK S-35392A Configuration of Register 1. Real-time data register The real-time data register is a 7-byte register that stores the data of year, month, day, day of the week, hour, minute, and second in the BCD code. To Write/Read real-time data 1 access, transmit/receive the data of year in B7, month, day, day of the week, hour, minute, second in B0, in 7-byte ...
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... Example: 19 seconds (s1, s2, s4, s8, s10, s20, s40 ( bit 24-hour expression, users can Write either (H1, H2, H4, H8, H10, H20, Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK S-35392A ( ( ...
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... REAL-TIME CLOCK S-35392A 2. Status register 1 Status register 1-byte register that is used to display and set various modes. The bit configuration is shown below RESET R POC This flag is used to confirm whether the power is on. The power-on detector operates at power-on and B0 is set to “1”. ...
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... Table 10 shows how to select the mode. To use INT 2 Table 10 Output Modes for INT2FE 0 No interrupt 1 Output of user-set frequency 0 Per-minute edge interrupt 1 Minute-periodical interrupt 1 (50% duty) 0 Alarm 2 interrupt Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK INT2ME INT2AE TEST R/W R/W R/W R/W: Read/Write INT 2 Pin INT 2 Pin Output Mode S-35392A 13 ...
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... REAL-TIME CLOCK S-35392A 4. INT1 register and INT2 register The INT1 register is to set up the alarm time. The INT2 register is to set up the output of user-set frequency or alarm interrupt. To switch the output mode, use the status register 2. The INT1 register works as an alarm-time data register in the alarm 1 interrupt mode selected by users. The INT1 flag (B3 in the status register) displays the alarm time when it matches ...
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... Figure 15 Example of Output from INT2 Register (Data Register for Output Frequency SC7 SC5 SC6 R/W R/W R/W Figure 13 INT1 Register (Free Register R/W R/W R/W Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK SC8 SC9 SC10 R/W R/W R/W R/W: Read/Write SC11 SC12 SC13 R/W R/W R/W R/W: Read/Write S-35392A 15 ...
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... REAL-TIME CLOCK S-35392A 5. Clock-correction register The clock-correction register is a 1-byte register that is used to correct advance/delay of the clock. When not using this function, set this register to “00h”. Regarding the register values, refer to “ Function to Clock-Correction” R/W R/W 6. Free register The free register is a 1-byte SRAM type register that can be set freely by users ...
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... The POC flag is set to “0” due to initialization. (Refer to “ Register Status After Initialization”.) For the regular operation of power-on detection circuit, as seen in Figure 18, the period to power-up the S-35392A is that the voltage reaches 1.3 V within 10 ms after setting the IC’s power supply voltage When the POC flag (B0 in the status register) is not in “ ...
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... SDA Device code + command : Output from S-35392A : Input from master device 18 00 (Y), 01 (M), 01 (D), 0 (day of the week), 00 (H), 00 (M), 00 (S) “ b” (In B6, B5, B4, the data of B6, B5 the status register 1 at initialization is set. ...
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... Low Power Supply Voltage Detection Circuit The S-35392A has a low power supply voltage detection circuit, so that users can monitor drops in the power supply voltage by reading the BLD flag (B1 in the status register 1). There is a hysteresis width of approx. 0.15 V (Typ.) between detection voltage and release voltage (refer to “ ...
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... REAL-TIME CLOCK S-35392A Correction of Nonexistent Data and End-of-Month When users write the real-time data, the S-35392A checks it. In case that the data is invalid, the S-35392A does the following procedures. 1. Processing of nonexistent data Register Year data Month data Day data ...
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... Figure 22 Alarm Interrupt Output Timing (1/2) Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK INT 2 pin, at the alarm time Alarm 1 output (B3 in status register 1) Alarm 2 interrupt (INT2 pin)/ alarm 2 output (B2 in status register 1) Year Change by program Status register 1 reading *1 S-35392A Configuration of 21 ...
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... REAL-TIME CLOCK S-35392A Alarm setting of “H (hour)” Status register 2 setting • Alarm 1 function INT1ME = INT1FE = 0 • Alarm 2 interrupt INT2ME = INT2FE = 0 Real-time data (H − Change by program INT1AE/INT2AE Alarm time matches INT1 flag/ INT2 flag Alarm time matches INT2 pin *1. If users clear INT2AE once ...
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... Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK pin, when the first minute-carry processing is INT 2 Minute-carry processing *1 . Minute-carry Minute-carry processing processing pin is in “L”. INT 2 S-35392A pin, INT ...
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... Correction is performed once every 20 seconds (or 60 seconds). The minimum resolution is approx. 3 ppm (or approx. 1 ppm) and the S-35392A corrects in the range of −195.3 to +192.2 ppm (or of −65.1 to +64.1 ppm). (Refer to Table 12.) Users can set up this function by using the clock-correction register. Regarding how to calculate the setting data, refer to “ ...
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... Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK S-35392A − (Target oscillation frequency *2 ) × (Minimum resolution *2 ) pin. ) − (Current oscillation frequency actual measurement value) × (Minimum resolution ...
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... REAL-TIME CLOCK S-35392A 2. Setting value for register and correction value Table 13 Setting Value for Register and Correction Value (Minimum Resolution: 3.052 ppm ( Table 14 Setting Value for Register and Correction Value (Minimum Resolution: 1.017 ppm (B0 = 1)) ...
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... How to confirm setting value for register and result of correction The S-35392A does not adjust the frequency of the crystal oscillation by using the clock-correction function. Therefore users cannot confirm corrected or not by measuring output 32.768 kHz. When the function to clock-correction is being used, the cycle clock pulse output from the Figure 27 ...
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... SDA line. After that, the S-35392A sends an acknowledgment signal back, and set the SDA line to “L” at the 9-bit clock pulse. The S-35392A does not output an acknowledgment signal is that the access is not being done regularly. ...
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... Read-data mode by the Read/Write bit “1”. The data is output from B7 in 1-byte. Input an acknowledgment signal from the master device every moment that the S-35392A outputs 1-byte data. However, do not input an acknowledgment signal (input NO_ACK) for the last data-byte output from the master device. This procedure notifies the completion of Read ...
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... After detecting a start condition, S-35392A receives device code and command. The S-35392A enters the Write-data mode by the Read/Write bit “0”. Input data from 1-byte. The S-35392A outputs an acknowledgment signal (“L”) every moment that 1-byte data is input. After receiving the acknowledgment signal which is for the last byte-data, input a stop condition to the S-35392A to finish access ...
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... SCL 0 SDA Device code + I/O mode switching *1. Set NO_ACK = 1 in Read. *2. Transmit ACK = 0 from the master device to the S-35392A in Read. (3) Status register 1 access and status register 2 access SCL SDA * Status register 1 selected Status register 2 selected *2. Set NO_ACK = 1 in Read. Figure 36 Status Register 1 Access and Status Register 2 Access ...
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... Device code + command I/O mode switching * INT1 register selected INT2 register selected *2. Set NO_ACK = 1 in Read. *3. Transmit ACK = 0 from the master device to the S-35392A in Read. Figure 37 INT1 Register Access and INT2 Register Access SCL SDA I/O mode switching * INT1 register selected INT2 register selected *2 ...
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... B7 Device code + command Clock correction data I/O mode switching Figure 39 Clock Correction Register Access Device code + command Free register data Figure 40 Free Register Access Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK I/O mode switching S-35392A 33 ...
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... S-35392A does not operate the next procedure because the internal circuit keeps the state prior to interruption. The S-35392A does not have a reset pin so that users usually reset its internal circuit by inputting a stop condition. However, if the SDA line is outputting “L” (during output of acknowledgment signal or Read), the S-35392A does not accept a stop condition from the master device ...
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... Read real-time data 1 Read status register 2 START Power-on Wait for 0 POC = 1 YES Initialize NO POC = 0 YES NO BLD = 0 YES register TEST = 0 YES END Figure 42 Example of Initialization Flowchart Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK Initialization after power-on Example of real-time data setting S-35392A 35 ...
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... Caution 1. Because the I/O pin has no protective diode on the VDD side, the relation of V but pay careful attention to the specifications. 2. Start communication under stable condition after power-on the power supply in the system. VDD S-35392A VSS XOUT XIN C g Caution Start communication under stable condition after power-on the power supply in the system. ...
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... Increase the insulation resistance between pins and the substrate wiring patterns of XIN and XOUT. (3) Do not place any signal or power lines close to the oscillator. (4) Locating the GND layer immediately below the oscillator is recommended. (5) Locate the bypass capacitor adjacent to the power supply pin of the S-35392A. Parasitic capacitance Crystal oscillator: 32.768 kHz ...
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... S-35392A 2. Measurement of oscillation frequency When the S-35392A is turned on, a signal of 32.768 kHz is output from the 32KO pin. Turn the power on and measure the signal with a frequency counter following the circuit configuration shown in Figure 47. Remark If the error range is ± 1 ppm in relation to 32.768 kHz, the time is shifted by approximately 2.6 seconds per month (calculated using the following expression). – ...
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... R L Figure 48 Crystal Oscillator Setting Flow Seiko Instruments Inc. 2-WIRE REAL-TIME CLOCK value in accordance with the flowchart below. Set to center of variable *3 capacitance NO Frequency YES Make fine adjustment of frequency using variable capacitance value (equivalent serial resistance S-35392A g 39 ...
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... REAL-TIME CLOCK S-35392A Product Name Structure S-35392A - I8T1 G Precautions • Although the IC contains a static electricity protection circuit, static electricity or voltage that exceeds the limit of the protection circuit should not be applied. • Seiko Instruments Inc. assumes no responsibility for the way in which this IC is used in products created using this IC or for the specifications of that product, nor does Seiko Instruments Inc ...
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... SCL frequency [kHz] characteristics 25°C, C 1.0 0.9 0.8 0 0.6 I DD1 0.5 [µA] 0 0.3 0.2 0 [pF] g characteristics 25° ∆f/f 0 [ppm] −10 −20 −30 −40 − [V] DD S-35392A = 400 500 = ...
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... REAL-TIME CLOCK S-35392A (7) Oscillation frequency vs. Temperature characteristics 20 0 −20 −40 ∆f/f −60 [ppm] −80 −100 −120 −140 −40 −25 0 (9) Output current characteristics 1 (V INT 2 32KO pin OL1 [mA (11) BLD detection, release voltage, V Temperature characteristics 1 ...
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... Use of the information described herein for other purposes and/or reproduction or copying without the express permission of Seiko Instruments Inc. is strictly prohibited. The products described herein cannot be used as part of any device or equipment affecting the human body, such as exercise equipment, medical equipment, security systems, gas equipment, or any apparatus installed in airplanes and other vehicles, without prior written permission of Seiko Instruments Inc ...