s-35190a Seiko Instruments Inc., s-35190a Datasheet
s-35190a
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s-35190a Summary of contents
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... REAL-TIME CLOCK The S-35190A is a CMOS 3-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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... SNT-8A Top view 8 INT 1 7 XOUT 2 XIN 6 3 VSS 4 5 Figure 3 Pin Configuration (S-35190A-I8T1G) Table 1 I/O Nch open-drain output Output (no protective diode at VDD) − − CMOS input Input (built-in pull-down resistor. no protective diode at VDD) CMOS input Input (no protective diode at VDD) Nch open-drain output ...
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... SCK pin. The status is in high impedance when the CS pin is in “L” or open, so that the S-35190A does not transmit data. Setting the CS pin to “H” level from “L” or open, this SIO pin goes in the input status so that it receives the command data. This pin has CMOS input and Nch open drain output. • ...
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... REAL-TIME CLOCK S-35190A Block Diagram XIN Oscillator Timing generator 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, INT register 1 Comparator 1 Second Minute Hour Comparator 2 INT register 2 ...
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... Ta = − +85 ° C − L Table pF, 32.768 kHz) manufactured by Seiko Instruments Inc.) L Conditions Within 10 seconds − − 1 Applied to XIN pin Applied to XOUT pin Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK S-35190A Rating V − − − − ...
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... REAL-TIME CLOCK S-35190A DC Electrical Characteristics (Ta = −40 to +85°C, V Parameter Symbol Current I DD1 consumption 1 Current I DD2 consumption 2 Input current I IZH leakage 1 Input current I IZL leakage 2 Input current 1 I IH1 Input current 2 I IH2 Input current 3 I IH3 Output current I OZH leakage 1 ...
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... outside the IC. Therefore, use this value only as a reference value. L Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK S-35190A kΩ SIO Remark The power supplies of the IC and load have the same electrical potential. Figure 9 Output Load Circuit (Ta = − ...
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... REAL-TIME CLOCK S-35190A CSH SCK t DS SIO Figure 10 Timing Diagram 1 during 3-wire Communication Input data Figure 11 Timing Diagram 2 during 3-wire Communication Output data Figure 12 Timing Diagram 3 during 3-wire Communication 8 t ISU SCK 20% 80% 20 SCK SCK ...
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... After setting the CS pin “H”, transmit the 4-bit fixed code “0110”, after that, transmit a 3-bit command and 1-bit Read/Write command. Next, data is output or input from B7. Regarding details, refer to “ Serial Interface” Fixed code Command 1-byte data Figure 13 Data Communication Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK Read/Write bit S-35190A 9 ...
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... S-35190A 2. Configuration of command 8 types of command are available for the S-35190A, The S-35190A does Read/Write the various registers by inputting these fixed codes and commands. The S-35190A does not perform any operation with any codes and commands other than those below. Fixed Command ...
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... D20 Start bit of real-time data 2 data access H10 H20 m10 m20 s8 s10 s2 s4 s20 Figure 14 Real-time Data Register Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK Y40 Y80 m40 s40 B0 S-35190A 11 ...
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... REAL-TIME CLOCK S-35190A Year data (00 to 99): Y1, Y2, Y4, Y8, Y10, Y20, Y40, Y80 Sets the lower two digits of the Western calendar year (00 to 99) and links together with the auto calendar function until 2099. Example: 2053 (Y1, Y2, Y4, Y8, Y10, Y20, Y40, Y80 ...
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... B4 B3 INT1 SC0 SC1 R R/W R R/W Figure 15 Status Register more. This flag is Read-only. When this flag is “1”, be sure DET Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK INT2 BLD POC Read Write : Read/Write DET Low Power Supply S-35190A ) or less. Users 13 ...
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... REAL-TIME CLOCK S-35190A 3. Status register 2 Status register 1-byte register that is used to display and set various modes. The bit configuration is shown below INT1FE INT1ME R/W R TEST This is a test flag for SII. Be sure to set this flag to “0” in use. If this flag is set to “1”, be sure to initialize to set “0”. ...
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... Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK H10 H2 H20 m10 m20 m40 − − − − S-35190A 0 A2WE B0 AM/ A2HE PM B0 A2mE B0 15 ...
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... REAL-TIME CLOCK S-35190A (2) Output of user-set frequency The INT register 1-byte data register to set up the output frequency. Setting each bit the register to “1”, the frequency which corresponds to the bit is output in the AND-form. SC4 to SC6 is 3-bit SRAM type registers that can be freely set by users ...
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... The free register is a 1-byte SRAM type register that can be set freely by users R/W R R/W R/W R/W Figure 20 Clock-Correction Register R/W R/W R/W Figure 21 Free Register Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK R/W R/W R/W R/W: Read/Write R/W R/W R/W R/W: Read/Write S-35190A 17 ...
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... Register Status After Initialization ”.) For the regular operation of power-on detection circuit, as seen in Figure 22 , the period to power-up the S-35190A is that the voltage reaches 1.3 V within 10 ms after setting the IC’s power supply voltage When the power-on detection circuit is not working normally is ...
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... Fixed code + command B7 B5 Write “1” to reset flag and SC0. Figure 23 Status Register 1 Data at Initialization Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK Read from status register Not reset S-35190A 0 19 ...
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... S-35190A Low Power Supply Voltage Detection Circuit The S-35190A 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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... Rev.2.4 _00 Correction of Nonexistent Data and End-of-Month When users write the real-time data, the S-35190A checks it. In case that the data is invalid, the S-35190A does the following procedures. 1. Processing of nonexistent data Register Year data Month data Day data Day of the week data ...
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... REAL-TIME CLOCK S-35190A INT Pin Output Mode These are selectable for the INT pin output mode; Alarm 1 interrupt, alarm 2 interrupt, the output of user-set frequency, per-minute edge interrupt output, minute-periodical interrupt output 1 and 2, 32.768 kHz output. In alarm 1 interrupt/output of frequency; set data in the INT register 1. In alarm 2 interrupt, set data in the INT register 2. To swith the output mode, use the status register 2. Refer to “ ...
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... Period when alarm time matches Figure 27 Alarm Interrupt Output Timing (2/2) Figure 28 Output Timing of User-set Frequency Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK Yx Alarm interrupt Change by program *1 Alarm time *2 matches OFF Change by program OFF S-35190A ( ...
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... REAL-TIME CLOCK S-35190A 3. Per-minute edge interrupt output Per-minute edge interrupt output is the function to output “L” from the INT pin, when the first minute-carry processing is done, after selecting the output mode. To set the pin output to “H”, set “0” in INT1ME in the status register 2 to turn off the output mode of per-minute edge interrupt ...
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... Second data of writing: "50" s The output period is shorter. Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK Minute-carry processing 7 Minute-carry processing 7 Minute-carry processing 7 Second data of writing: "10" s The output period is longer. S-35190A 7 ...
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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-35190A 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. 3-WIRE REAL-TIME CLOCK S-35190A − (Target oscillation frequency *2 ) × (Minimum resolution * − (Current oscillation frequency actual measurement value) × (Minimum resolution ...
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... REAL-TIME CLOCK S-35190A 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-35190A 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 INT pin changes once in 20 times or 60 times, as shown in Figure 33 ...
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... REAL-TIME CLOCK S-35190A Serial Interface The S-35190A receives various commands via 3-wire serial interface to Read/Write data. Regarding transmission is as follows. 1. Data Read When data is input from the SIO pin in synchronization with the falling of the SCK clock after setting the CS pin to “H”, the data is loaded internally in synchronization with the next rising of the SCK clock ...
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... During reading: Output mode switching Figure 35 Real-Time Data 2 Access Fixed code + Status data command Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK Second data During reading: Input mode switching 16 B0 During reading: Input mode switching S-35190A 31 ...
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... REAL-TIME CLOCK S-35190A (4) INT register 1 access and INT register 2 access In Read/Write the INT register 1, data varies depending on the setting of the status register 2. Be sure to Read/Write the INT register 1 after setting the status register 2. When setting the alarm by using the status register 2, these registers work as 3-byte alarm time data registers, in other statuses, they work as 1-byte registers ...
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... Figure 39 Clock Correction Register Access Fixed code + Free register data command Figure 40 Free Register Access Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK 16 B0 During reading: Input mode switching 16 B0 During reading: Input mode switching S-35190A 33 ...
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... REAL-TIME CLOCK S-35190A Flowchart of Initialization at Power-on and Example of Real-time Data Set-up Figure 41 shows the flowchart of initialization at power-on and an example of real-time data set-up. Regarding how to apply power, refer to “ Power-on Detection Circuit and Register Status” unnecessary for users to comply with this flowchart of real-time data strictly ...
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... INT CS SIO Figure 42 Application Circuit 1 10 kΩ INT CS 10 kΩ SIO SCK Figure 43 Application Circuit 2 Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK S-35190A V CC System power supply VCC CPU VSS ≥ possible System power supply VCC CPU VSS ...
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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-35190A. Parasitic capacitance C g Crystal oscillator: 32.768 kHz *1 ...
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... Rev.2.4 _00 2. Measurement of oscillation frequency When the S-35190A is turned on, the internal power-on detector operates and a signal output from the INT pin to select the crystal oscillator and optimize the C counter following the circuit configuration shown in Figure signal is not output, the power-on detector does not operate normally. Turn off the power and then turn it on again. For how to apply power, refer to “ ...
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... REAL-TIME CLOCK S-35190A 3. Adjustment of oscillation frequency (1) Adjustment by setting C Matching of the crystal oscillator with the nominal frequency must be performed with the stray capacitance on the board included. Select a crystal oscillator and optimize the C Fixed capacitor Request a crystal manufacturer for matching evaluation between the IC and a crystal. The recommended crystal characteristic values are Ω ...
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... Seiko Instruments Inc. assume any responsibility for any infringement of patents or copyrights by products that include this IC either in Japan or in other countries. G Package name (abbreviation) and IC packing specification J8T1 : 8-Pin SOP (JEDEC), Tape T8T1 : 8-Pin TSSOP, Tape I8T1 : SNT-8A, Tape Product name Seiko Instruments Inc. 3-WIRE REAL-TIME CLOCK S-35190A 39 ...
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... REAL-TIME CLOCK S-35190A Characteristics (Typical Data) (1) Standby current vs ° 1.0 0.8 0.6 I DD1 [µA] 0.4 0 (3) Current consumption during operation vs. Input clock characteristics ° DD2 15 [µ 200 400 SCK frequency [kHz] (5) Standby current vs. C ...
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... INT pin ° 5 OL1 3 [V] OUT CS pin ° C 800 700 = 5 600 500 I IH 400 300 V DD 200 100 [V] IN S-35190A = 5 vs OUT OL1 3 ...
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... REAL-TIME CLOCK S-35190A (13) BLD detection, release voltage, V Temperature characteristics 1.4 1.2 1.0 0.8 BLD [V] 0.6 0.4 0.2 0 −40 − (Min) vs. DDT = Release voltage Detection voltage V (Min) DDT [°C] Seiko Instruments Inc. Rev.2.4 _00 ...
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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 ...