S-35390A-I8T1G

Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A The S-35390A 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 is 1.3 V to 5.5 V so that this IC can be used for various power supplies from main supply to backup battery. Due to the 0.25 µA current consumption and wide range of power supply voltage at time keeping, this IC makes the battery life longer. In the system which operates with a backup battery, the included free registers can be used as the function for user’s backup memory. Users always can take back the information in the registers which is stored before power-off the main power supply, after the voltage is restored. This IC has the function to correct advance/delay of the clock data speed, in the wide range, which is caused by the oscillation circuit’s frequency deviation. Correcting according to the temperature change by combining this function and a temperature sensor, it is possible to make a high precise clock function which is not affected by the ambient temperature. Features • • • • • • • • • • • • Low current consumption : 0.25 µA typ. (VDD = 3.0 V, Ta = 25°C) Wide range of operating voltage : 1.3 to 5.5 V Built-in clock-correction function Built-in free user register 2-wire (I2C-bus) CPU interface Built-in alarm interrupter Built-in flag generator during detection of low power voltage or at power-on Auto calendar up to the year 2099, automatic leap year calculation function Built-in constant voltage circuit Built-in 32.768 kHz crystal oscillator (Cd built in, Cg external) Packages : 8-Pin SOP (JEDEC), 8-Pin TSSOP, SNT-8A. Lead-free product Applications • • • • • • • • • Mobile game devices Mobile AV devices Digital still cameras Digital video cameras Electronic power meters DVD recorders TVs, VCRs Mobile phones, PHS Car navigation Packages Drawing Code Package FJ008-A FT008-A PH008-A Tape FJ008-D FT008-E PH008-A Reel FJ008-D FT-008E PH008-A Land − − PH008-A Package Name 8-Pin SOP (JEDEC) 8-Pin TSSOP SNT-8A Seiko Instruments Inc. 1 2-WIRE REAL-TIME CLOCK S-35390A Pin Configuration 8-Pin SOP (JEDEC) Top view INT1 XOUT XIN VSS Rev.2.4_00 1 2 3 4 8 7 6 5 VDD SDA SCL INT2 Figure 1 Pin Configuration (S-35390A-J8T1G) 8-Pin TSSOP Top view INT1 XOUT XIN VSS 1 2 3 4 8 7 6 5 VDD SDA SCL INT2 Figure 2 Pin Configuration (S-35390A-T8T1G) SNT-8A Top view INT1 XOUT XIN VSS Figure 3 1 2 3 4 8 7 6 5 VDD SDA SCL INT2 Pin Configuration (S-35390A-I8T1G) List of Pin Table 1 Pin No. 1 Symbol Description Output pin for interrupt signal 1 Connection pin for crystal oscillator I/O Configuration Nch open-drain output (no protective diode at VDD) INT1 XOUT XIN VSS INT2 Output − − 2 3 4 5 6 7 8 − SCL SDA VDD GND pin Output pin for interrupt signal 2 Input pin for serial clock I/O pin for serial data Pin for positive power supply − Nch open-drain output Output (no protective diode at VDD) CMOS input Input (no protective diode at VDD) Nch open-drain output Bi-directional (no protective diode at VDD) CMOS input − − 2 Seiko Instruments Inc. Rev.2.4_00 Pin Function • SDA (I/O for serial data) pin 2-WIRE REAL-TIME CLOCK S-35390A This pin is to data input/output for I2C-bus interface. This pin inputs/outputs data by synchronizing with a clock pulse from the SCL pin. This pin has CMOS input and Nch open drain output. Generally in use, pull up this pin to the VDD potential via a resistor, and connect it to any other device having open drain or open collector output with wired-OR connection. • SCL (input for serial clock) pin This pin is to input a clock pulse for I2C-bus interface. The SDA pin inputs/outputs data by synchronizing with the clock pulse. • XIN, XOUT (crystal oscillator connect) pin Connect a crystal oscillator between XIN and XOUT. • INT1 (output for interrupt signal 1) pin This pin outputs a signal of interrupt, or a clock pulse. By using the status register 2, users can select either of; alarm 1 interrupt, output of user-set frequency, per-minute edge interrupt, minute-periodical interrupt 1, minute-periodical interrupt 2, or 32.768 kHz output. This pin has Nch open drain output. • INT2 (output for interrupt signal 2) pin This pin outputs a signal of interrupt, or a clock pulse. By using the status register 2, users can select either of; alarm 2 interrupt, output of user-set frequency, per-minute edge interrupt or minute-periodical interrupt 1. This pin has Nch open drain output. • VDD (positive power supply) pin Connect this VDD pin with a positive power supply. Regarding the values of voltage to be applied, refer to “ Recommended Operation Conditions”. • VSS pin Connect this VSS pin to GND. Equivalent Circuits of I/O Pin SDA SCL Figure 4 SDA Pin INT1, INT2 Figure 5 SCL Pin Figure 6 INT1 Pin, INT2 Pin Seiko Instruments Inc. 3 2-WIRE REAL-TIME CLOCK S-35390A Block Diagram Rev.2.4_00 XIN XOUT Oscillator Diviver, timing generator INT1 register INT1 controller INT1 Clock correction register Status register 1 Status register 2 Comparator 1 Real-time data register Day of Second Minute Hour Day Month Year the week Comparator 2 Free register Low power supply voltage detector Power-on detector Constant-voltage circuit VSS INT2 register INT2 controller Serial interface SDA SCL INT2 VDD Shift register Figure 7 4 Seiko Instruments Inc. Rev.2.4_00 Absolute Maximum Ratings Table 2 Parameter Symbol Applicable Pin 2-WIRE REAL-TIME CLOCK S-35390A Rating Unit Power supply voltage VDD − VSS − 0.3 to VSS + 6.5 V Input voltage VIN SCL, SDA VSS − 0.3 to VSS + 6.5 V VSS − 0.3 to VSS + 6.5 Output voltage VOUT V SDA, INT1, INT2 Operating ambient − −40 to +85 °C Topr temperature*1 Storage temperature Tstg − −55 to +125 °C *1. Conditions with no condensation or frost. Condensation and frost cause short circuiting between pins, resulting in a malfunction. Caution The absolute maximum ratings are rated values exceeding which the product could suffer physical damage. These values must therefore not be exceeded under any conditions. Recommended Operation Conditions Table 3 Parameter Symbol Conditions Min. Typ. Max. Power supply voltage *1 VDD Ta = −40 to +85°C 1.3 3.0 5.5 Time keeping power Ta = −40 to +85°C VDET − 0.15 − 5.5 V VDDT supply voltage *2 Crystal oscillator CL value CL − − 6 7 pF *1. The power supply voltage that allows communication under the conditions shown in Table 8 of “ AC Electrical Characteristics”. *2. The power supply voltage that allows time keeping. For the relationship with VDET (low power supply voltage detection voltage), refer to “ Characteristics (Typical Data)”. (VSS = 0 V) Unit V Oscillation Characteristics Table 4 (Ta = 25°C, VDD = 3.0 V, VSS = 0 V, VT-200 crystal oscillator (CL = 6 pF, 32.768 kHz) manufactured by Seiko Instruments Inc.) Parameter Symbol Conditions Min. Typ. Max. Unit Oscillation start voltage VSTA Within 10 seconds 1.1 − 5.5 V Oscillation start time tSTA − − − 1 s IC-to-IC frequency δIC − −10 − +10 ppm deviation*1 Frequency voltage δV VDD = 1.3 to 5.5 V −3 − +3 ppm/V deviation External capacitance Cg Applied to XIN pin − − 9.1 pF Internal oscillation Cd Applied to XOUT pin − 8 − pF capacitance *1. Reference value Seiko Instruments Inc. 5 2-WIRE REAL-TIME CLOCK S-35390A DC Electrical Characteristics Rev.2.4_00 Table 5 DC Characteristics (VDD = 3.0 V) (Ta = −40 to +85°C, VSS = 0 V,VT-200 crystal oscillator (CL = 6 pF, 32.768 kHz, Cg = 9.1 pF) manufactured by Seiko Instruments Inc.) Parameter Symbol Applicable Pin Conditions Min. Typ. Max. Unit Current consumption 1 IDD1 − Out of communication − 0.25 0.93 µA During communication Current consumption 2 IDD2 − − 6 14 µA (SCL = 100 kHz) Input current leakage 1 IIZH SCL, SDA VIN = VDD −0.5 − 0.5 µA Input current leakage 2 IIZL SCL, SDA VIN = VSS −0.5 − 0.5 µA Output current leakage 1 IOZH SDA, INT1 , INT2 VOUT = VDD −0.5 − 0.5 0.5 VSS + 5.5 0.2 × VDD − − µA Output current leakage 2 IOZL Input voltage 1 Input voltage 2 Output current 1 VIH VIL IOL1 SDA, INT 1 , INT2 SCL, SDA SCL, SDA VOUT = VSS − − −0.5 − − − µA 0.8 × VDD VSS−0.3 V V INT1 , INT2 SDA − VOUT = 0.4 V VOUT = 0.4 V − 3 5 0.65 5 10 1 mA mA V Output current 2 Power supply voltage detection voltage IOL2 VDET 1.35 Table 6 DC Characteristics (VDD = 5.0 V) (Ta = −40 to +85°C, VSS = 0 V, VT-200 crystal oscillator (CL = 6 pF, 32.768 kHz, Cg = 9.1 pF) manufactured by Seiko Instruments Inc.) Parameter Symbol Applicable Pin Conditions Min. Typ. Max. Unit Current consumption 1 IDD1 − Out of communication − 0.3 1.1 µA During communication Current consumption 2 IDD2 − − 14 30 µA (SCL = 100 kHz) Input current leakage 1 IIZH SCL, SDA VIN = VDD −0.5 − 0.5 µA Input current leakage 2 IIZL SCL, SDA VIN = VSS −0.5 − 0.5 µA Output current leakage 1 IOZH SDA, INT 1 , INT2 VOUT = VDD −0.5 − 0.5 µA Output current leakage 2 IOZL Input voltage 1 Input voltage 2 Output current 1 VIH VIL IOL1 SDA, INT1 , INT2 SCL, SDA SCL, SDA VOUT = VSS − − −0.5 − − − 0.5 VSS + 5.5 0.2 × VDD − − µA 0.8 × VDD VSS−0.3 V V INT 1 , INT2 SDA − VOUT = 0.4 V VOUT = 0.4 V − 5 6 0.65 8 13 1 mA mA V Output current 2 Power supply voltage detection voltage IOL2 VDET 1.35 6 Seiko Instruments Inc. Rev.2.4_00 AC Electrical Characteristics Table 7 Measurement Conditions 2-WIRE REAL-TIME CLOCK S-35390A VDD Input pulse voltage Input pulse rise/fall time Output determination voltage Output load VIH = 0.9 × VDD, VIL = 0.1 × VDD 20 ns VOH = 0.5 × VDD, VOL = 0.5 × VDD 100 pF + pull-up resistor 1 kΩ R = 1 kΩ SDA C = 100 pF Remark The power supplies of the IC and load have the same electrical potential. Output Load Circuit Figure 8 Table 8 AC Electrical Characteristics Parameter SCL clock frequency SCL clock low time SCL clock high time SDA output delay time*1 Start condition setup time Start condition hold time Data input setup time Data input hold time Stop condition setup time SCL, SDA rise time SCL, SDA fall time Bus release time Noise suppression time Symbol fSCL tLOW tHIGH tPD tSU.STA tHD.STA tSU.DAT tHD.DAT tSU.STO tR tF tBUF tI VDD *2 ≥ 1.3 V Min. Typ. Max. 0 − 100 4.7 − − 4 − − 3.5 − − 4.7 − − 4 − − 250 − − 0 − − 4.7 − − 1 − − 0.3 − − 4.7 − − 100 − − (Ta = −40 to +85°C) VDD *2 ≥ 3.0 V Unit Min. Typ. Max. 0 − 400 kHz µs 1.3 − − µs 0.6 − − 0.9 µs − − 0.6 µs − − 0.6 µs − − 100 − − ns 0 µs − − µs 0.6 − − 0.3 µs − − 0.3 µs − − µs 1.3 − − 50 ns − − *1. Since the output format of the SDA pin is Nch open-drain output, SDA output delay time is determined by the values of the load resistance (RL) and load capacity (CL) outside the IC. Therefore, use this value only as a reference value. *2. Regarding the power supply voltage, refer to “ Recommended Operation Conditions”. tF tHIGH tLOW tR SCL tHD.DAT tSU.DAT tSU.STO tSU.STA tHD.STA SDA (Input from S-35390A) tPD tBUF SDA (Output from S-35390A) Figure 9 Bus Timing Seiko Instruments Inc. 7 2-WIRE REAL-TIME CLOCK S-35390A Configuration of Data Communication 1. Configuration of data communication Rev.2.4_00 For data communication, the master device in the system generates a start condition for the S-35390A. 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. If data I/O has been completed, finish communication by inputting a stop condition to the S-35390A. The master device generates an acknowledgment signal for every 1-byte. Regarding details, refer to “ Serial Interface”. Start condition Device code STA 0 1 1 0 C2 Command C1 C0 Read/Write bit Acknowledgment bit R/W ACK Stop condition 1-byte data B7 B6 B5 B4 B3 B2 B1 B0 ACK STP Figure 10 Data Communication 8 Seiko Instruments Inc. Rev.2.4_00 2. Configuration of command 2-WIRE REAL-TIME CLOCK S-35390A 8 types of command are available for the S-35390A, The S-35390A does Read/Write the various registers by inputting these codes and commands. The S-35390A does not perform any operation with any codes and commands other than those below. Table 9 Device Code C2 C1 C0 Command Description Status register 1 access Status register 2 access List of Command Data B7 B6 B5 B4 SC1*2 32kE Y8 M8 D8 −*6 H8 m8 s8 B3 INT1*3 B2 INT2*3 B1 BLD*4 B0 POC*4 0 0 0 0 0 1 RESET*1 12 / 24 SC0*2 INT1FE INT1ME INT1AE 0 1 0 Real-time data 1 access (year data to) Y1 M1 D1 W1 H1 m1 s1 Y2 M2 D2 W2 H2 m2 s2 Y4 M4 D4 W4 H4 m4 s4 INT2FE INT2ME INT2AE TEST*5 Y40 Y80 Y10 Y20 −*6 −*6 −*6 M10 *6 *6 − − D20 D10 *6 *6 *6 − −*6 − − −*6 H10 H20 AM / PM −*6 m10 m20 m40 *6 − s10 s20 s40 0 1 1 Real-time data 2 access (hour data to) H1 m1 s1 H2 m2 s2 H4 m4 s4 H8 m8 s8 H10 m10 s10 H20 m20 s20 AM / PM m40 s40 −*6 −*6 −*6 INT1 register access −*6 −*6 −*6 −*6 A1WE W1 W2 W4 (alarm time 1: week/hour/minute) 0110 H8 H10 H20 AM / PM A1HE H1 H2 H4 (INT1AE = 1, INT1ME = 0, A1mE m8 m10 m20 m1 m2 m4 m40 1 0 0 INT1FE = 0) INT1 register access *2 SC3 *2 SC4 *2 (output of user-set frequency) 1 Hz 2 Hz 4 Hz 8 Hz 16 Hz SC2 (INT1ME = 0, INT1FE = 1) INT2 register access −*6 −*6 −*6 −*6 A2WE W1 W2 W4 (alarm time 2: week/hour/minute) H8 H10 H20 AM / PM A2HE H1 H2 H4 (INT2AE = 1, INT2ME = 0, A2mE m8 m10 m20 m1 m2 m4 m40 1 0 1 INT2FE = 0) INT2 register access *2 SC6 *2 SC7 *2 1 Hz 2 Hz 4 Hz 8 Hz 16 Hz SC5 (output of user-set frequency) (INT2ME = 0, INT2FE = 1) 1 1 0 Clock correction register access V0 V1 V2 V3 V4 V5 V6 V7 F0 F1 F2 F3 F4 F5 F6 F7 1 1 1 Free register access *1. Write-only flag. The S-35390A initializes by writing “1” in this register. *2. Scratch bit. A R/W-enabled, user-free register. *3. Read-only flag. Valid only when using the alarm function. When the alarm time matches, this flag is set to “1”, and it is cleared to “0” when Read. *4. Read-only flag. “POC” is set to “1” when power is applied. It is cleared to “0” when Read. Regarding “BLD”, refer to “ Low Power Supply Voltage Detection Circuit”. *5. Test bit for SII. Be sure to set “0” in use. *6. No effect by Write. It is “0” when Read. Seiko Instruments Inc. 9 2-WIRE REAL-TIME CLOCK S-35390A Configuration of Register 1. Real-time data register Rev.2.4_00 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. When you skip the procedure to access the data of year, month, day, day of the week, Read/Write real-time data 2 access. In this case, transmit/receive the data of hour in B7, minute, second in B0, in 3-byte. Year data (00 to 99) Start bit of real-time data 1 data access Y1 B7 Month data (01 to 12) M1 B7 Day data (01 to 31) D1 B7 Day of the week data (00 to 06) W1 B7 Hour data (00 to 23 or 00 to 11) Start bit of real-time data 2 data access H1 B7 H2 H4 H8 H10 H20 0 B0 W2 W4 0 0 0 0 0 B0 D2 D4 D8 D10 D20 0 0 B0 M2 M4 M8 M10 0 0 0 B0 Y2 Y4 Y8 Y10 Y20 Y40 Y80 B0 AM / PM Minute data (00 to 59) m1 B7 m2 m4 m8 m10 m20 m40 0 B0 Second data (00 to 59) s1 B7 s2 s4 s8 s10 s20 s40 0 B0 Figure 11 Real-Time Data Register 10 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A 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) = (1, 1, 0, 0, 1, 0, 1, 0) Month data (01 to 12): M1, M2, M4, M8, M10 Example: December (M1, M2, M4, M8, M10, 0, 0, 0) = (0, 1, 0, 0, 1, 0 ,0 ,0) Day data (01 to 31): D1, D2, D4, D8, D10, D20 The count value is automatically changed by the auto calendar function. 1 to 31: Jan., Mar., May, July, Aug., Oct., Dec., 1 to 30: April, June, Sep., Nov. 1 to 29: Feb. (leap year), 1 to 28: Feb. (non-leap year) Example: 29 (D1, D2, D4, D8, D10, D20, 0, 0) = (1, 0, 0, 1, 0, 1, 0, 0) Day of the week data (00 to 06): W1, W2, W4 A septenary up counter. Day of the week is counted in the order of 00, 01, 02, …, 06, and 00. Set up day of the week and the count value. Hour data (00 to 23 or 00 to 11): H1, H2, H4, H8, H10, H20, AM / PM In a 12-hour expression, write 0; AM, 1; PM in the AM / PM bit. In a 24-hour expression, users can Write either 0 or 1. 0 is read when the hour data is from 00 to 11, and 1 is read when from 12 to 23. Example (12-hour expression): 12 p.m. (H1, H2, H4, H8, H10, H20, AM/PM, 0) = (0, 1, 0, 0, 1, 0, 1, 0) Example (24-hour expression): 22 (H1, H2, H4, H8, H10, H20, AM/PM, 0) = (0, 1, 0, 0, 0, 1, 1, 0) Minute data (00 to 59): m1, m2, m4, m8, m10, m20, m40 Example: 32 minutes (m1, m2, m4, m8, m10, m20, m40, 0) = (0, 1, 0, 0, 1, 1, 0, 0) Example: 55 minutes (m1, m2, m4, m8, m10, m20, m40, 0) = (1, 0, 1, 0, 1, 0, 1, 0) Second data (00 to 59): s1, s2, s4, s8, s10, s20, s40 Example: 19 seconds (s1, s2, s4, s8, s10, s20, s40, 0) = (1, 0, 0, 1, 1, 0, 0, 0) Seiko Instruments Inc. 11 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 2. Status register 1 Status register 1 is a 1-byte register that is used to display and set various modes. The bit configuration is shown below. B7 RESET W B6 B5 SC0 R/W B4 SC1 R/W B3 INT1 R R: W: R/W: B2 INT2 R B1 BLD R B0 POC R 12 / 24 R/W Read Write Read/Write Figure 12 B0 : POC Status Register 1 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”. This flag is Read-only. Once it is read, it is automatically set to “0”. When this flag is “1”, be sure to initialize. Regarding the operation after power-on, refer to “ Power-on Detection Circuit and Register Status”. B1 : BLD This flag is set to “1” when the power supply voltage decreases to the level of detection voltage (VDET) or less. Users can detect a drop in the power supply voltage. This flag is set to “1” once, is not set to “0” again even if the power supply increases to the level of detection voltage (VDET) or more. This flag is Read-only. When this flag is “1”, be sure to initialize. Regarding the operation of the power supply voltage detection circuit, refer to “ Low Power Supply Detection Circuit”. B2 : INT2, B3 : INT1 This flag indicates the time set by alarm and when the time has reached it. This flag is set to “1” when the time that users set by using the alarm interrupt function has come. The INT1 flag in “1” at alarm 1 interrupt mode, the INT2 flag in “1” at alarm 2 interrupt mode. This flag is Read-only. This flag is read once, is set to “0” automatically. B4 : SC1, B5 : SC0 These flags are SRAM type registers, they are 2 bits as a whole, can be freely set by users. B6 : 12 / 24 This flag is used to set 12-hour or 24-hour expression. 0 : 12-hour expression 1 : 24-hour expression B7 : RESET The internal IC is initialized by setting this bit to “1”. This bit is Write-only. It is always “0” when Read. When applying the power supply voltage to the IC, be sure to write “1” to this bit to initialize the circuit. Regarding each status of data after initialization, refer to “ Register Status After Initialization”. 12 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A 3. Status register 2 Status register 2 is a 1-byte register that is used to display and set various modes. The bit configuration is shown below. B7 I NT1FE R/W B6 B5 INT1AE R/W B4 32kE R/W B3 INT2FE B2 INT2ME R/W B1 INT2AE B0 TEST INT1ME R/W R/W R/W R/W R/W: Read/Write Figure 13 B0 : TEST Status Register 2 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”. B1 : INT2AE, B2 : INT2ME, B3 : INT2FE These bits are used to select the output mode for the INT2 pin. Table 10 shows how to select the mode. To use an alarm 2 interrupt, set alarm interrupt mode, then access the INT2 register. Table 10 Output Modes for INT2 Pin INT2 Pin Output Mode No interrupt Output of user-set frequency Per-minute edge interrupt Minute-periodical interrupt 1 (50% duty) Alarm 2 interrupt INT2AE INT2ME INT2FE *1. 0 0 0 *1 − 0 1 −*1 1 0 *1 − 1 1 1 0 0 Don’t care (Both of 0 and 1 are acceptable). B4 : 32kE, B5 : INT1AE, B6 : INT1ME, B7 : INT1FE These bits are used to select the output mode for the INT 1 pin. Table 11 shows how to select the mode. To use alarm 1 interrupt, access the INT1 register after setting the alarm interrupt mode. Table 11 Output Modes for INT1 Pin 32kE INT1AE INT1ME INT1FE *1. 0 0 0 −*1 0 0 −*1 0 1 0 0 1 0 1 0 0 1 1 −*1 −*1 1 Don’t care (Both of 0 and 1 are acceptable). 0 1 0 1 0 1 −*1 INT 1 Pin Output Mode No interrupt Output of user-set frequency Per-minute edge interrupt Minute-periodical interrupt 1 (50% duty) Alarm 1 interrupt Minute-periodical interrupt 2 32.768 kHz output Seiko Instruments Inc. 13 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 4. INT1 register and INT2 register The INT1 and INT2 registers are to set up the output of user-set frequency, or to set up alarm interrupt. Users are able to switch the output mode by using the status register 2. If selecting to use the output mode for alarm interrupt by status register 2; these registers work as alarm-time data registers. If selecting the output of user-set frequency by status register 2; these registers work as data registers to set the frequency for clock output. From each INT1 and INT2 pin, a clock pulse and alarm interrupt are output. (1) Alarm interrupt Users can set the alarm time (the data of day of the week, hour, minute) by using the INT1 and INT2 registers which are 3-byte data registers. The configuration of register is as well as the data register of day of the week, hour, minute, in the real-time data register; is expressed by the BCD code. Do not set a nonexistent day. Users are necessary to set up the alarm-time data according to the 12/24 hour expression that they set by using the status register 1. INT1 register W1 B7 W2 W4 0 0 0 0 A1WE B0 H10 H20 AM / A1HE PM B0 INT2 register W1 B7 W2 W4 0 0 0 0 A2WE B0 H10 H20 AM / A2HE PM B0 H1 B7 H2 H4 H8 H1 B7 H2 H4 H8 m1 B7 m2 m4 m8 m10 m20 m40 A1mE B0 m1 B7 m2 m4 m8 m10 m20 m40 A2mE B0 Figure 14 INT1 Register and INT2 Register (Alarm-Time Data) The INT1 register has A1WE, A1HE, A1mE at B0 in each byte. It is possible to make data valid; the data of day of the week, hour, minute which are in the corresponded byte; by setting these bits to “1”. This is as well in A2WE, A2HE, A2mE in the INT2 register. Setting example: alarm time “7:00 pm” in the INT1 register (a) 12-hour expression (status register 1 B6 = 0) set up 7:00 PM Data written to INT1 register −*1 −*1 −*1 −*1 −*1 Day of the week Hour 1 1 1 0 0 Minute 0 0 0 0 0 B7 *1. Don’t care (Both of 0 and 1 are acceptable). (b) 24-hour expression (status register 1 B6 = 1) −*1 0 0 −*1 1 0 0 1 1 B0 set up 19:00 PM Data written to INT1 register *1 *1 *1 *1 *1 *1 − − − − − − Day of the week Hour 1 0 0 1 1 0 Minute 0 0 0 0 0 0 B7 *1. Don’t care (Both of 0 and 1 are acceptable). *2. Set up the AM / PM flag along with the time setting. − 1*2 0 *1 0 1 1 B0 14 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A (2) Output of user-set frequency The INT1 and INT2 registers are 1-byte data registers to set up the output frequency. Setting each bit B7 to B3 in the register to “1”, the frequency which corresponds to the bit is output in the AND-form. SC2 to SC4 in the INT1 register, and SC5 to SC7 in the INT2 register are 3-bit SRAM type registers that can be freely set by users. B7 1 Hz R/W B6 2 Hz R/W B5 4 Hz R/W B4 8 Hz R/W B3 16 Hz R/W B2 SC2 R/W B1 SC3 R/W B0 SC4 R/W R/W: Read/Write Figure 15 B7 1 Hz R/W B6 2 Hz R/W INT1 Register (Data Register for Output Frequency) B5 B4 8 Hz R/W B3 16 Hz R/W B2 SC5 R/W B1 SC6 R/W B0 SC7 R/W 4 Hz R/W R/W: Read/Write Figure 16 Example: B7 to B3 = 50h INT2 Register (Data Register for Output Frequency) 16 Hz 8 Hz 4 Hz 2 Hz 1 Hz INT1 pin or INT2 pin output Status register 2 • Set to INT1FE or INT2FE = 1 Figure 17 Example of Output from INT1 and INT2 Registers (Data Register for Output Frequency) Seiko Instruments Inc. 15 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 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”. B7 V0 R/W B6 V1 R/W B5 V2 R/W B4 V3 R/W B3 V4 R/W B2 V5 R/W B1 V6 R/W B0 V7 R/W R /W: Read/Write Figure 18 Clock-Correction Register 6. Free register This free register is a 1-byte SRAM type register that can be set freely by users. B7 F0 R/W B6 F1 R/W B5 F2 R/W B4 F3 R/W B3 F4 R/W B2 F5 R/W B1 F6 R/W B0 F7 R/W R/W: Read/Write Figure 19 Free Register 16 Seiko Instruments Inc. Rev.2.4_00 Power-on Detector and Register Status 2-WIRE REAL-TIME CLOCK S-35390A The power-on detection circuit operates by power-on the S-35390A, as a result each register is cleared; each register is set as follows. Real-time data register : Status register 1 : Status register 2 : INT1 register : INT2 register : Clock correction register : Free register : 00 (Y), 01 (M), 01 (D), 0 (day of the week), 00 (H), 00 (M), 00 (S) “01h” “01h” “80h” “00h” “00h” “00h” “1” is set in the POC flag (B0 in the status register 1) to indicate that power has been applied. To correct the oscillation frequency, the status register 2 goes in the mode the output of user-set frequency, so that 1 Hz clock pulse is output from the INT1 pin. When “1” is set in the POC flag, be sure to initialize. The POC flag is set to “0” due to initialization so that the output of user-set frequency mode is cleared. (Refer to “ Register Status After Initialization”.) For the regular operation of power-on detection circuit, as seen in Figure 20, the period to power-up the S-35390A is that the voltage reaches 1.3 V within 10 ms after setting the IC’s power supply voltage at 0 V. When the power-on detection circuit is not working normally is; the POC flag (B0 in the status register) is not in “1”, or 1 Hz is not output from the INT1 pin. In this case, power-on the S-35390A once again because the internal data may be in the indefinite status. Do not transmit data immediately after power-on at least 0.5 sec because the power-on detection circuit is operating. Within 10 ms 1.3 V 0V *1 *1. 0 V indicates that there are no potential differences between the VDD pin and VSS pin of the S-35390A. Figure 20 How to Raise the Power Supply Voltage Seiko Instruments Inc. 17 2-WIRE REAL-TIME CLOCK S-35390A Register Status After Initialization The status of each register after initialization is as follows. Real-time data register : Status register 1 : Rev.2.4_00 Status register 2 : INT1 register : INT2 register : Clock correction register : Free register : 00 (Y), 01 (M), 01 (D), 0 (day of the week), 00 (H), 00 (M), 00 (S) “0 B6 B5 B4 0 0 0 0 b” (In B6, B5, B4, the data of B6, B5, B6 in the status register 1 at initialization is set. Refer to Figure 21.) “00h” “00h” “00h” “00h” “00h” Write to status register 1 1 9 18 1 Read from status register 1 9 18 SCL R/W ACK START START STOP ACK R/W NO_ACK ACK STOP 0 0 110000 1 L LH LL L L L 0 SDA 0 11 0 0000 10100000 Device code + command B7 B5 Write “1” to reset flag and SC0. Device code + command B7 B5 : Not reset : Output from S-35390A : Input from master device Figure 21 Data of Status Register 1 at Initialization 18 Seiko Instruments Inc. Rev.2.4_00 Low Power Supply Voltage Detection Circuit 2-WIRE REAL-TIME CLOCK S-35390A The S-35390A 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 “ Characteristics (Typical Data)”). The low power supply voltage detection circuit does the sampling operation only once in one sec for 15.6 ms. If the power supply voltage decreases to the level of detection voltage (VDET) or less, “1” is set to the BLD flag so that sampling operation stops. Once “1” is detected in the BLD flag, no sampling operation is performed even if the power supply voltage increases to the level of release voltage or more, and “1” is held in the BLD flag. After initialization, or once the BLD flag is read, the BLD flag is automatically set to “0” to restart the sampling operation. If the BLD flag is “1” even after the power supply voltage is recovered, the internal circuit may be in the indefinite status. In this case, be sure to initialize the circuit. Without initializing, Read in the next BLD flag is done after sampling, the BLD flag gets reset to “0”. In this case, be sure to initialize although the BLD flag is in “0” because the internal circuit may be in the indefinite status. VDD Detection voltage Hysteresis width 0.15 V approximately Release voltage BLD flag reading 15.6 ms 1s 1s Stop Stop Stop Sampling pulse BLD flag Figure 22 Timing of Low Power Supply Voltage Detection Circuit Circuits Power-on and Low Power Supply Voltage Detection Figure 23 shows the changes of the POC flag and BLD flag due to VDD fluctuation. VDD Low power supply voltage detection voltage Low power supply voltage detection voltage VSS POC flag BLD flag Status register 1 reading Figure 23 POC Flag and BLD Flag Seiko Instruments Inc. 19 2-WIRE REAL-TIME CLOCK S-35390A Correction of Nonexistent Data and End-of-Month Rev.2.4_00 When users write the real-time data, the S-35390A checks it. In case that the data is invalid, the S-35390A does the following procedures. 1. Processing of nonexistent data Table 12 Processing of Nonexistent Data Register Year data Month data Day data Day of the week data 24-hour Hour data *1 12-hour Minute data Second data *2 Normal Data 00 to 99 01 to 12 01 to 31 0 to 6 0 to 23 0 to 11 00 to 59 00 to 59 Nonexistent Data XA to XF, AX to FX 00, 13 to 19, XA to XF 00, 32 to 39, XA to XF 7 24 to 29, 3X, XA to XF 12 to 19, 2X, 3X, XA to XF 60 to 79, XA to XF 60 to 79, XA to XF Result 00 01 01 0 00 00 00 00 *1. In a 12-hour expression, Write the AM / PM flag (B1 in hour data in the real-time data register). In 24-hour expression, the AM / PM flag in the real-time data register is omitted. However in the flag in Read, users are able to read 0; 0 to 11, 1; 12 to 23. *2. Processing of nonexistent data, regarding second data, is done by a carry pulse which is generated one sec after, after Write. At this point the carry pulse is sent to the minute-counter. 2. Correction of end-of-month A nonexistent day, such as February 30 and April 31, is set to the first day of the next month. 20 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A INT1 Pin and INT2 Pin Output Mode These are selectable for the output mode for INT1 and INT2 pins; Alarm interrupt, the output of user-set frequency, per-minute edge interrupt output, minute-periodical interrupt output 1. In the INT1 pin output mode, in addition to the above modes, minute-periodical interrupt output 2 and 32.768 kHz output are also selectable. To switch the output mode, use the status register 2. Refer to “3. Status register 2” in “ Configuration of Register”. When switching the output mode, be careful of the output status of the pin. Especially, when using alarm interrupt/output of frequency, switch the output mode after setting “00h” in the INT1/INT2 register. In 32.768 kHz output/per-minute edge interrupt output/minute-periodical interrupt output, it is unnecessary to set data in the INT1/INT2 register for users. Refer to the followings regarding each operation of output modes. 1. Alarm interrupt output Alarm interrupt output is the function to output “L” from the INT1 / INT2 pin, at the alarm time which is set by user has come. If setting the pin output to “H”, turn off the alarm function by setting “0” in INT1AE/INT2AE in the status register 2. To set the alarm time, set the data of day of the week, hour and minute in the INT1/INT2 register. Refer to “4. INT1 register and INT2 register” in “ Configuration of Register”. Alarm setting of W (day of the week), H (hour), m (minute)” Status register 2 setting • INT1 pin output mode 32kE = 0, INT1ME = INT1FE = 0 • INT2 pin output mode INT2ME = INT2FE = 0 INT1 register INT2 register mx Hx Wx INTx register alarm enable flag • AxHE = AxmE = AxWE = "1" Comparator Alarm interrupt Second Minute Hour Real-time data W (day of the week) Real-time data H h (m − 1) m 59 s Change by program INT1AE/INT2AE Day of Day the week Month Year H h 00 m 00 s 01 s 59 s H h (m + 1) m 00 s Change by program Change by program *1 Alarm time matches INT1 pin/INT2 pin OFF Period when alarm time matches *1. If users clear INT1AE/INT2AE once; “L” is not output from the INT1 / INT 2 pin by setting INT1AE/INT2AE enable again, within a period when the alarm time matches real-time data. Figure 24 Alarm Interrupt Output Timing (1/2) Seiko Instruments Inc. 21 2-WIRE REAL-TIME CLOCK S-35390A Alarm setting of “H (hour)” Status register 2 setting • INT1 pin output mode 32kE = 0, INT1ME = INT1FE = 0 • INT2 pin output mode INT2ME = INT2FE = 0 INT1 register INT2 register INTx register alarm enable flag • AxHE = AxmE = AxWE = "1" Rev.2.4_00 mx Hx Wx Dx Mx Yx Comparator Alarm interrupt Second Minute Hour Real-time data Day of Day the week Month Year Real-time data (H − 1) h 59 m 59 s Change by program H h 00 m 00 s 01 s 59 s H h 01 m 00 s H h 59 m 59 s Change by program (H + 1) h 00 m 00 s Change by program Change by program INT1AE/INT2AE *1 *1 Alarm time matches INT1 pin/INT2 pin OFF Alarm time matches*2 OFF Period when alarm time matches *1. If users clear INT1AE/INT2AE once; “L” is not output from the INT1 / INT 2 pin by setting INT1AE/INT2AE enable again, within a period when the alarm time matches real-time data. *2. If turning the alarm output on by changing the program, within the period when the alarm time matches real-time data, “L” is output again from the INT1 / INT2 pin when the minute is counted up. Figure 25 Alarm Interrupt Output Timing (2/2) 2. Output of user-set frequency The output of user-set frequency is the function to output the frequency which is selected by using data, from the INT1 / INT 2 pin, in the AND-form. Set up the data of frequency in the INT1/INT2 register. Refer to “4. INT1 register and INT2 register” in “ Configuration of Register”. Status register 2 setting • INT1 pin output mode 32kE = 0, INT1AE = Don’t care (0 or 1), INT1ME = 0 • INT2 pin output mode INT2AE = Don’t care (0 or 1), INT2ME = 0 Change by program INT1FE/INT2FE Free-run output starts INT1 pin/INT2 pin OFF Figure 26 Output Timing of User-set Frequency 22 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A 3. Per-minute edge interrupt output Per-minute edge interrupt output is the function to output “L” from the INT 1 / INT2 pin, when the first minute-carry processing is done, after selecting the output mode. To set the pin output to “H”, turn off the output mode of per-minute edge interrupt. In the INT 1 pin output mode, input “0” in INT1ME in the status register 2. In the INT2 pin output mode, input “0” in INT2ME. Status register 2 setting • INT1 pin output mode 32kE = 0, INT1AE = Don’t care (0 or 1), INT1FE = 0 • INT2 pin output mode INT2AE = Don’t care (0 or 1), INT2FE = 0 Change by program INT1ME/INT2ME Minute-carry processing OFF Minute-carry processing INT1 pin/INT2 pin "L" is output again if this period is within 7.9 ms*1. *1. Pin output is set to “H” by disabling the output mode within 7.9 ms, because the signal of this procedure is maintained for 7.9 ms. Note that pin output is set to “L” by setting enable the output mode again. Figure 27 Timing of Per-Minute Edge Interrupt Output 4. Minute-periodical interrupt output 1 The minute-periodical interrupt 1 is the function to output the one-minute clock pulse (Duty 50%) from the INT 1 / INT2 pin, when the first minute-carry processing is done, after selecting the output mode. Status register 2 setting • INT1 pin output mode 32kE = 0, INT1AE = 0 • INT2 pin output mode INT2AE = 0 INT1ME, INT1FE INT2ME, INT2FE Minute-carry processing INT1 pin/INT2 pin Minute-carry processing Minute-carry processing Minute-carry processing Minute-carry processing Change by program (OFF) 30 s 30 s 30 s 30 s 30 s 30 s 30 s 30 s 30 s "L" is output again if this period is within 7.9 ms*1. "H" is output again if this period is within 7.9 ms "L" is output at the next minute-carry processing *1. Setting the output mode disable makes the pin output “H”, while the output from the INT 1 / INT2 pin is in “L”. Note that pin output is set to “L” by setting enable the output mode again. Figure 28 Timing of Per-Minute Steady Interrupt Output 1 Seiko Instruments Inc. 23 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 5. Minute-periodical interrupt output 2 (only in the INT1 pin output mode) The output of minute-periodical interrupt 2 is the function to output “L”, for 7.9 ms, from the INT 1 pin, synchronizing with the first minute-carry processing after selecting the output mode. However, in Read in the real-time data register, the procedure delays at max. 0.5 sec thus output “L” from the INT 1 pin also delays at max. 0.5 sec. In Write in the real-time data register, some delay is made in the output period due to Write timing and the second-data during Write. (a) During normal operation Minute-carry processing Minute-carry processing Minute-carry processing INT1 pin 7.9 ms 60 s 7.9 ms 60 s 7.9 ms (b) During Read in the real-time data register (Normal minutecarry processing) Minute-carry processing Minute-carry processing Minute-carry processing INT1 pin 7.9 ms 0.5 s Max. 60 s 7.9 ms 60 s 7.9 ms Serial communication Real-time data read command Real-time Real-time data Real-time data reading read command data reading (c) During Write in the real-time data register Minute-carry processing Minute-carry processing Minute-carry processing INT1 pin 7.9 ms 55 s 45 s Real-time data write timing Second data of writing: "50" s The output period is shorter. Second data of writing: "10" s The output period is longer. 10 s 7.9 ms 80 s 30 s 50 s 7.9 ms Figure 29 Timing of Minute-periodical Interrupt Output 2 24 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A 6. Operation of power-on detection circuit (only in the INT1 pin output mode) When power is applied to the S-35390A, the power-on detection operates to set “1” in the POC flag (B0 in the status register 1). A 1 Hz clock pulse is output from the INT 1 pin. Status register 2 setting • 32kE = 0, INT1AE = INT1ME = 0 INT1FE OFF INT1 pin Change by reset command 0.5 s 0.5 s Figure 30 Output Timing of INT 1 Pin during Operation of Power-on Detection Circuit Function to Clock-Correction The function to clock-correction is to correct advance/delay of the clock due to the deviation of oscillation frequency, in order to make a high precise clock. For correction, the S-35390A adjusts the clock pulse by using a certain part of the dividing circuit, not adjusting the frequency of the crystal oscillator. Correction is performed once every 20 seconds (or 60 seconds). The minimum resolution is approx. 3 ppm (or approx. 1 ppm) and the S-35390A corrects in the range of −195.3 to +192.2 ppm (or of −65.1 to +64.1 ppm). (Refer to Table 13.) Users can set up this function by using the clock-correction register. Regarding how to calculate the setting data, refer to “1. How to calculate”. When not using this function, be sure to set “00h”. Table 13 Function to Clock-Correction Correction Minimum resolution Correction range B0 = 0 Every 20 seconds 3.052 ppm −195.3 to +192.2 ppm B0 = 1 Every 60 seconds 1.017 ppm −65.1 to +64.1 ppm Seiko Instruments Inc. 25 2-WIRE REAL-TIME CLOCK S-35390A 1. How to calculate (1) If current oscillation frequency > target frequency (in case the clock is fast) Rev.2.4_00 Correction value = 128 − Integral value *1 (Current oscillation frequency *3 *2 actual measurement value ) − (Target oscillation frequency ) (Current oscillation frequency *2 actual measurement value ) × (Minimum resolution ) *4 Caution The figure range which can be corrected is that the calculated value is from 0 to 64. *1. Convert this value to be set in the clock correction register. example 1”. For how to convert, refer to “(a) Calculation *2. Measurement value when 1 Hz clock pulse is output from the INT 1 pin (or INT2 pin). *3. Target value of average frequency when the clock correction function is used. *4. Refer to Table 13. (a) Calculation example 1 In case of current oscillation frequency actual measurement value = 1.000070 [Hz], target oscillation frequency = 1.000000 [Hz], B7 = 0 (Minimum resolution = 3.052 ppm) (1.000070) − (1.000000)  Correction value = 128 − Integral value   (1.000070) × (3.052 × 10−6)  = 128 − Integral value (22.93)= 128 − 22 = 106 Convert the correction value “106” to 7-bit binary and obtain “1101010b”. Reverse the correction value “1101010b” and set it to B6 to B0 of the clock correction register. Thus, set the clock correction register: (B7, B6, B5, B4, B3, B2, B1, B0) = (0, 1, 0, 1, 0, 1, 1, 0) (2) If current oscillation frequency < target frequency (in case the clock is slow) (Target oscillation frequency) − Correction value = Integral value (Current oscillation frequency actual measurement value) (Minimum resolution) (Current oscillation frequency × actual measurement value) +1 Caution The figure range which can be corrected is that the calculated value is from 0 to 62. (a) Calculation example 2 In case of current oscillation frequency actual measurement value = 0.999920 [Hz], target oscillation frequency = 1.000000 [Hz]. B7 = 0 (Minimum resolution = 3.052 ppm) (1.000000) − (0.999920)  +1 Correction value = Integral value   (0.999920) × (3.052 × 10-6)  = Integral value (26.21) + 1 = 26 + 1 = 27 Thus, set the clock correction register: (B7, B6, B5, B4, B3, B2, B1, B0) = (1, 1, 0, 1, 1, 0, 0, 0) (b) Calculation example 3 In case of current oscillation frequency actual measurement value = 0.999920 [Hz], target oscillation frequency = 1.000000 [Hz], B7 = 1 (Minimum resolution = 1.017 ppm) (1.000000) − (0.999920)  +1 Correction value = Integral value  0.999920) × (1.017 × 10-6)  ( = Integral value (78.66) + 1 Thus, this calculated value exceeds the correctable range 0 to 62, B7 = “1” (minimum resolution = 1.017 ppm) indicates the correction is impossible. 26 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A 2. Setting value for register and correction value Table 14 Setting Value for Register and Correction Value (Minimum Resolution: 3.052 ppm (B0 = 0)) B7 1 0 1 B6 1 1 0 B5 1 1 1 B4 1 1 1 B3 1 1 1 • • • 0 0 0 1 1 1 • • • 0 0 0 B2 1 1 1 B1 0 0 0 B0 0 0 0 0 1 0 1 0 1 1 0 0 1 1 0 0 0 0 1 1 1 0 0 0 1 1 1 0 0 0 1 1 1 0 0 0 1 1 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 Correction Value [ppm] 192.3 189.2 186.2 • • • 6.1 3.1 0 −3.1 −6.1 −9.2 • • • −189.2 −192.3 −195.3 Rate [s/day] 16.61 16.35 16.09 • • • 0.53 0.26 0 −0.26 −0.53 −0.79 • • • −16.35 −16.61 −16.88 Table 15 Setting Value for Register and Correction Value (Minimum Resolution: 1.017 ppm (B0 = 1)) B7 1 0 1 B6 1 1 0 B5 1 1 1 B4 1 1 1 B3 1 1 1 • • • 0 0 0 1 1 1 • • • 0 0 0 B2 1 1 1 B1 0 0 0 B0 1 1 1 0 1 0 1 0 1 1 0 0 1 1 0 0 0 0 1 1 1 0 0 0 1 1 1 0 0 0 1 1 1 0 0 0 1 1 1 1 1 1 1 1 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 Correction Value [ppm] 64.1 63.1 62.0 • • • 2.0 1.0 0 −1.0 −2.0 −3.0 • • • −63.1 −64.1 −65.1 Rate [s/day] 5.54 5.45 5.36 • • • 0.18 0.09 0 −0.09 −0.18 −0.26 • • • −5.45 −5.54 −5.62 Seiko Instruments Inc. 27 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 3. How to confirm setting value for register and result of correction The S-35390A does not adjust the frequency of the crystal oscillation by using the clock-correction function. Therefore users cannot confirm if it is corrected or not by measuring output 32.768 kHz. When the function to clock-correction is being used, the cycle of 1 Hz clock pulse output from the INT 1 pin changes once in 20 times or 60 times, as shown in Figure 31. INT1 pin (1 Hz output) a a 19 times or 59 times a b Once a B0 = 0, a : 19 times, b : Once B0 = 1, a : 59 times, b : Once Figure 31 Confirmation of Correction Result Measure a and b by using the frequency counter*1. Calculate the average frequency (Tave) based on the measurement results. B0 = 0, Tave = (a × 19 + b) ÷ 20 B0 = 1, Tave = (a × 59 + b) ÷ 60 Calculate the error of the clock based on the average frequency (Tave). The following shows an example for confirmation. Confirmation example: When B0 =0, 66h is set Measurement results: a = 1.000080 Hz, b = 0.998493 Hz Clock Correction Register Setting Value Average Frequency [Hz] Before correction 00 h (Tave = a) 1.000080 After correction 66 h (Tave = (a × 19 + b) ÷ 20) 1.00000065 Calculating the average frequency allows to confirm the result of correction. Per Day [s] 86393 86399.9 *1. Use a frequency counter with 7-digit or greater precision. Caution Measure the oscillation frequency under the usage conditions. 28 Seiko Instruments Inc. Rev.2.4_00 Serial Interface 2-WIRE REAL-TIME CLOCK S-35390A The S-35390A receives various commands via I2C-bus serial interface to Read/Write data. Regarding transmission is as follows. 1. Start condition A start condition is when the SDA line changes “H” to “L” when the SCL line is in “H”, so that the access starts. 2. Stop condition A stop condition is when the SDA line changes “L” to “H” when the SCL line is in “H”, and the access stops, so that the S-35390A gets standby. tSU.STA tHD.STA tSU.STO SCL SDA Start condition Figure 32 Start/Stop Conditions Stop condition 3. Data transfer and acknowledgment signal Data transmission is performed for every 1-byte, after detecting a start condition. Transmit data while the SCL line is in “L”, and be careful of spec of tSU.DAT and tHD. DAT when changing the SDA line. If the SDA line changes while the SCL line is in “H”, the data will be recognized as start/stop condition in spite of data transmission. Note that by this case, the access will be interrupted. During data transmission, every moment receiving 1-byte data, the devices which work for receiving data send an acknowledgment signal back. For example, as seen in Figure 33, in case that the S-35390A is the device working for receiving data and the master device is the one working for sending data; when the 8th clock pulse falls, the master device releases the SDA line. After that, the S-35390A sends an acknowledgment signal back, and set the SDA line to “L” at the 9th clock pulse. The S-35390A does not output an acknowledgment signal is that the access is not being done regularly. SCL (Input from S-35390A) tSU.DAT SDA (Output from master device) SDA (Input from S-35390A) 1 tHD.DAT 8 9 SDA is released High-Z Output acknowledgment (“L” active) Start condition High-Z tPD Figure 33 Output Timing of Acknowledgment Signal Seiko Instruments Inc. 29 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 The followings are Read/Write in the S-35390A. (1) Data Read in S-35390A After detecting a start condition, the S-35390A receives device code and command. The S-35390A enters the 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-35390A 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. Next, input a stop condition to the S-35390A to finish access. 1-byte data 1 9 18 SCL R/W NO_ACK START STOP ACK SDA 0 110 000 1 B7 B0 Device code + command : Output from S-35390A : Input from master device Input NO_ACK after the 1st byte of data has been output. Figure 34 Example of Data Read 1 (1-Byte Data Register) 3-byte data 1 9 18 27 36 SCL R/W START STOP NO_ACK ACK ACK SDA 0 11 00 1 11 ACK Device code + command B7 B0 B7 B0 B7 B0 : Output from S-35390A : Input from master device Figure 35 Input NO_ACK after the 3rd byte of data has been output. Example of Data Read 2 (3-Byte Data Register) 30 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A (2) Data Write in S-35390A After detecting a start condition, S-35390A receives device code and command. The S-35390A enters the Write-data mode by the Read/Write bit “0”. Input data from B7 to B0 in 1-byte. The S-35390A 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-35390A to finish access. 1-byte data 1 9 18 SCL R/W START STOP ACK ACK SDA 0 110000 0 B7 B0 Device code + command : Output from S-35390A : Input from master device Figure 36 Example of Data Write 1 (1-Byte Data Register) 3-byte data 1 9 18 27 36 SCL R/W STOP ACK START ACK ACK ACK SDA 0 110011 0 B7 B0 B7 B0 B7 B0 Device code + command : Output from S-35390A : Input from master device Figure 37 Example of Data Read 2 (3-Byte Data Register) Seiko Instruments Inc. 31 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 4. Data access (1) Real-time data 1 access 1 9 18 63 72 SCL R/W STOP START ACK ACK ACK SDA 0 11 00 1 0 ACK*1 *2 *2 Device code + command I/O mode switching B7 B0 Year data B7 B0 Second data I/O mode switching *1. Set NO_ACK = 1 in Read. *2. Transmit ACK = 0 from the master device to the S-35390A in Read. Figure 38 (2) Real-time data 2 access 1 9 18 27 36 Real-Time Data 1 Access SCL R/W START STOP ACK*2 ACK ACK*2 SDA 0 1100 11 ACK*1 Device code + command I/O mode switching B7 Hour data B0 B7 B0 B7 B0 Minute data Second data I/O mode switching *1. *2. Set NO_ACK = 1 in Read. Transmit ACK = 0 from the master device to the S-35390A in Read. Figure 39 Real-Time Data 2 Access (3) Status register 1 access and status register 2 access 1 9 18 SCL *1 START R/W STOP ACK ACK*2 SDA 0 11000 Device code + command I/O mode switching B7 B0 Status data I/O mode switching *1. *2. 0 : Status register 1 selected, 1 : Status register 2 selected Set NO_ACK = 1 for reading. Figure 40 Status Register 1 Access and Status Register 2 Access 32 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A (4) INT1 register access and INT2 register access In Read/Write the INT1 and INT2 registers, data varies depending on the setting of the status register 2. Be sure to Read/Write 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. When outputting the user-set frequency, they are the data registers to set up the frequency. Regarding details of each data, refer to “4. INT1 register and INT2 register” in “ Caution Configuration of Register”. Users cannot use both functions of alarm 1 interrupt and output of user-set frequency for the INT1 pin and INT2 pin simultaneously. 1 9 18 27 36 SCL *1 START R/W STOP ACK*3 ACK*2 ACK ACK*3 SDA 0 11010 Device code + command I/O mode switching B7 B0 B7 Hour data B0 B7 B0 Day of the week data Minute data I/O mode switching *1. *2. *3. 0 : INT1 register selected, 1 : INT2 register selected Set NO_ACK = 1 in Read. Transmit ACK = 0 from the master device to the S-35390A in Read. Figure 41 INT1 Register Access and INT2 Register Access 1 9 18 SCL *1 START R/W STOP ACK*2 ACK SDA 0 11010 Device code + command I/O mode switching B7 B0 Frequency setting data I/O mode switching *1. *2. 0 : INT1 register selected, 1 : INT2 register selected Set NO_ACK = 1 in Read. Figure 42 INT1 Register and INT2 Register (Data Register for Output Frequency) Access Seiko Instruments Inc. 33 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 (5) Clock correction register access 1 9 18 SCL R/W START STOP ACK*1 ACK SDA 0 110110 Device code + command I/O mode switching B7 B0 Clock correction data I/O mode switching *1. Set NO_ACK = 1 in Read. Figure 43 Clock Correction Register Access (6) Free register access 1 9 18 SCL R/W S TART S TOP A CK *1 A CK SDA 0 110111 Device code + command I/O mode switching *1. B7 B0 Free register data I/O mode switching Set NO_ACK = 1 in Read. Figure 44 Free Register Access 34 Seiko Instruments Inc. Rev.2.4_00 Reset After Communication Interruption 2-WIRE REAL-TIME CLOCK S-35390A In case of communication interruption in the S-35390A, for example, during communication the power supply voltage drops so that only the master device is reset; the S-35390A does not operate the next procedure because the internal circuit keeps the state prior to interruption. The S-35390A 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-35390A does not accept a stop condition from the master device. In this case, users are necessary to finish acknowledgment output or Read the SDA line. Figure 45 shows how to reset. First, input a start condition from the master device (The S-35390A cannot detect a start condition because the SDA line in the S-35390A is outputting “L”). Next, input a clock pulse equivalent to 7-byte data access (63-clock) from the SCL line. During this, release the SDA line for the master device. By this procedure, SDA I/O before interruption is finished, so that the SDA line in the S-35390A is released. After that, inputting a stop condition resets the internal circuit so that restore the regular communication. This reset procedure is recommended to perform at initialization of the system after rising the master device’s power supply voltage. Start condition 1 Stop condition 63 Clocks equivalent to 7-byte data access 2 8 9 62 SCL SDA (Output from master device) SDA (Output from S-35390A) SDA “L” “L” or High-Z High-Z “L” “L” or High-Z Figure 45 How to Reset Seiko Instruments Inc. 35 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 Flowchart of Initialization at Power-on and Example of Real-time Data Set-up Figure 46 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”. It is unnecessary for users to comply with this flowchart of real-time data strictly. And if using the default data at initializing, it is also unnecessary to set up again. START Power-on Wait for 0.5 s Read status register 1 NO POC = 1 YES Initialize (status register 1 B7 = 1) Initialization after power-on Read status register 1 NO POC = 0 YES BLD = 0 YES NO Set 24-hour/12-hour display to status register 1 Read status register 1 NG Confirm data in status register 1 OK Set real-time data 1 Example of real-time data setting Read real-time data 1 Read status register 2 NO TEST = 0 YES END Figure 46 Example of Initialization Flowchart 36 Seiko Instruments Inc. Rev.2.4_00 Examples of Application Circuits 10 kΩ INT1 VDD S-35390A VSS INT2 1 kΩ 1 kΩ 2-WIRE REAL-TIME CLOCK S-35390A VCC System power supply VCC 10 kΩ CPU SDA SCL XIN XOUT VSS Cg Caution 1. 2. Because the I/O pin has no protective diode on the VDD side, the relation of VCC ≥ VDD is possible, but pay careful attention to the specifications. Start communication under stable condition after power-on the power supply in the system. Figure 47 Application Circuit 1 System power supply VCC 10 kΩ INT1 VDD S-35390A VSS XIN XOUT INT2 1 kΩ 1 kΩ CPU 10 kΩ SDA SCL VSS Cg Caution Start communication under stable condition after power-on the power supply in the system. Figure 48 Caution Application Circuit 2 Set the constants after performing The above connection diagrams do not guarantee operation. sufficient evaluation using the actual application. Seiko Instruments Inc. 37 2-WIRE REAL-TIME CLOCK S-35390A Adjustment of Oscillation Frequency 1. Configuration of oscillator Rev.2.4_00 Since crystal oscillation is sensitive to external noise (the clock accuracy is affected), the following measures are essential for optimizing the oscillation configuration. (1) (2) (3) (4) (5) Place the S-35390A, crystal oscillator, and external capacitor (Cg) as close to each other as possible. Increase the insulation resistance between pins and the substrate wiring patterns of XIN and XOUT. Do not place any signal or power lines close to the oscillator. Locating the GND layer immediately below the oscillator is recommended. Locate the bypass capacitor adjacent to the power supply pin of the S-35390A. Parasitic capacitance*3 XIN Rf Crystal oscillator: 32.768 kHz CL = 6 pF*1 Cg = None*2 to 9.1 pF Cg XOUT Cd Rd Oscillator internal constant standard values: Rf = 100 MΩ Rd = 100 kΩ Cd = 8 pF Parasitic capacitance*3 S-35390A *1. When setting the value for the crystal oscillator’s CL as 7 pF, connect Cd externally if necessary. *2. Design the board so that the parasitic capacitance is 5 pF. *3. The oscillator operates unless Cg is not connected. Note that the oscillation frequency is in the direction that it advances. Figure 49 Connection Diagram 1 1 Crystal oscillator 2 XOUT 3 XIN 4 VSS Cg S-35390A 8 7 6 5 Locate the GND layer in the layer immediately below Figure 50 Caution Connection Diagram 2 1. When using the crystal oscillator with a CL exceeding the rated value (7 pF) (e.g : CL = 12.5 pF), oscillation operation may become unstable. Use a crystal oscillator with a CL value of 6 pF or 7 pF. 2. Oscillation characteristics is subject to the variation of each component such as substrate parasitic capacitance, parasitic resistance, crystal oscillator, and Cg. When configuring an oscillator, pay sufficient attention for them. 38 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A 2. Measurement of oscillation frequency When the S-35390A is turned on, the internal power-on detector operates and a signal of 1 Hz is output from the INT 1 pin to select the crystal oscillator and optimize the Cg value. Turn the power on and measure the signal with a frequency counter following the circuit configuration shown in Figure 51. If 1 Hz 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 “ Power-on Detector and Register Status”. Remark If the error range is ±1 ppm in relation to 1 Hz, the time is shifted by approximately 2.6 seconds per month (calculated using the following expression). 10–6 (1 ppm) × 60 seconds × 60 minutes × 24 hours × 30 days = 2.592 seconds VDD 1 kΩ 1 kΩ SDA SCL S-35390A XOUT INT1 Open or pull-up INT2 VSS Frequency counter XIN Cg 10 kΩ Figure 51 Configuration of Oscillation Frequency Measurement Circuit Caution 1. Use a high-accuracy frequency counter of 7 digits or more. 2. Measure the oscillation frequency under the usage conditions. 3. Since the 1 Hz signal continues to be output, initialization must be executed during normal operation. Seiko Instruments Inc. 39 2-WIRE REAL-TIME CLOCK S-35390A Rev.2.4_00 3. (1) Adjustment of oscillation frequency Adjustment by setting Cg 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 Cg value in accordance with the flowchart below. START Select a crystal oscillator*1 Variable capacitance Fixed capacitor YES Trimmer capacitor Set to center of variable capacitance*3 NO Set Cg NO Cg in specification Frequency Change Cg NO YES Optimal value*2 YES Make fine adjustment of frequency using variable capacitance NO YES END *1. Request a crystal manufacturer for matching evaluation between the IC and a crystal. The recommended crystal characteristic values are, CL value (load capacitance) = 6 pF, R1 value (equivalent serial resistance) = 50 kΩ max. *2. The Cg value must be selected on the actual PCB since it is affected by stray capacitance. Select the external Cg value in a range of 0 pF to 9.1 pF. *3. Adjust the rotation angle of the variable capacitance so that the capacitance value is slightly smaller than the center, and confirm the oscillation frequency and the center value of the variable capacitance. This is done in order to make the capacitance of the center value smaller than one half of the actual capacitance value because a smaller capacitance value increases the frequency variation. Figure 52 Crystal Oscillator Setting Flow Caution 1. The oscillation frequency varies depending on the ambient temperature and power supply voltage. Refer to “ Characteristics (Typical Data)”. 2. The 32.768 kHz crystal oscillator operates more slowly at an operating temperature than higher or lower 20 to 25°C. Therefore, it is recommended to set the oscillator to operate slightly faster at normal temperature. 40 Seiko Instruments Inc. Rev.2.4_00 Product Name Structure S-35390A xxxx G 2-WIRE REAL-TIME CLOCK S-35390A Package name (abbreviation) and IC packing specification J8T1 : 8-Pin SOP (JEDEC), Tape T8T1 : 8-Pin TSSOP, Tape I8T1 : SNT-8A, Tape Product name 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. assume any responsibility for any infringement of patents or copyrights by products that include this IC either in Japan or in other countries. Seiko Instruments Inc. 41 2-WIRE REAL-TIME CLOCK S-35390A Characteristics (Typical Data) (1) Standby current vs. VDD characteristics Rev.2.4_00 Ta = 25°C, CL = 6 pF (2) Current consumption when 32 kHz is output vs. VDD characteristics Ta = 25°C, CL = 6 pF 1.0 0.8 0.6 0.4 0.2 0 1.0 0.8 0.6 0.4 0.2 0 IDD1 [µA] IDD3 [µA] 0 1 2 3 4 VDD [V] 5 6 0 1 2 3 4 VDD [V] 5 6 (3) Current consumption during operation vs. Input clock characteristics Ta = 25°C, CL = 6 pF (4) Standby current vs. Temperature characteristics CL = 6 pF 50 45 40 35 30 IDD2 25 [µA] 20 15 10 5 0 VDD = 5.0 V 1.0 0.9 0.8 0.7 0.6 IDD1 0.5 [µA] 0.4 0.3 0.2 0.1 0 –40 –25 VDD = 3.0 V VDD = 5.0 V VDD = 3.0 V 0 100 200 300 400 SCLfrequency [kHz] 500 0 25 Ta [°C] 50 75 85 (5) Standby current vs. Cg characteristics Ta = 25°C, CL = 6 pF (6) Oscillation frequency vs. Cg characteristics Ta = 25°C, CL = 6 pF 1.0 0.9 0.8 0.7 0.6 IDD1 0.5 [µA] 0.4 0.3 0.2 0.1 0 ∆f/f [ppm] VDD = 5.0 V VDD = 3.0 V 0 2 4 6 Cg [pF] 8 10 100 80 60 40 20 0 –20 –40 –60 –80 –100 VDD = 5.0 V VDD = 3.0 V 0 2 4 6 Cg [pF] 8 10 42 Seiko Instruments Inc. Rev.2.4_00 2-WIRE REAL-TIME CLOCK S-35390A (7) Oscillation frequency vs. VDD characteristics Ta = 25°C, Cg = 7.5 pF (8) Oscillation frequency vs. Temperature characteristics Cg = 7.5 pF 50 40 30 20 ∆f/f [ppm] 10 0 –10 –20 –30 –40 –50 20 0 –20 –40 ∆f/f –60 [ppm] –80 –100 –120 0 1 2 3 4 VDD [V] 5 6 –140 –40 –25 0 25 Ta [°C] 50 75 85 VDD = 3.0 V VDD = 5.0 V (9) Oscillation start time vs. Cg characteristics Ta = 25°C (10) Output current characteristics 1 (VOUT vs. IOL1) INT1 pin, INT2 pin, Ta = 25°C 500 450 400 350 tSTA 250 [ms] 200 150 100 50 0 300 VDD = 5.0 V VDD = 3.0 V IOL1 [mA] 50 40 VDD = 5.0 V 30 20 10 0 VDD = 3.0 V 0 2 4 6 Cg [pF] 8 10 0 1 2 VOUT [V] 3 4 (11) Output current characteristics 2 (VOUT vs. IOL2) SDA pin, Ta = 25°C (12) BLD detection, release voltage, VDDT (Min) vs. Temperature characteristics CL = 6 pF 50 40 30 20 10 0 VDD = 5.0 V 1.4 1.2 1.0 BLD 0.8 [V] 0.6 0.4 0.2 0 0.5 1 1.5 VOUT [V] 2 2.5 Release voltage IOL2 [mA] Detection voltage VDDT (Min) VDD = 3.0 V 0 –40 –25 0 25 Ta [°C] 50 75 85 Seiko Instruments Inc. 43 5.02±0.2 8 5 1 4 0.20±0.05 1.27 0.4±0.05 No. FJ008-A-P-SD-2.1 TITLE No. SCALE UNIT SOP8J-D-PKG Dimensions FJ008-A-P-SD-2.1 mm Seiko Instruments Inc. 2.0±0.05 ø1.55±0.05 4.0±0.1(10 pitches:40.0±0.2) 0.3±0.05 ø2.0±0.05 5°max. 8.0±0.1 2.1±0.1 6.7±0.1 1 8 4 5 Feed direction No. FJ008-D-C-SD-1.1 TITLE No. SCALE UNIT SOP8J-D-Carrier Tape FJ008-D-C-SD-1.1 mm Seiko Instruments Inc. 60° 2±0.5 Enlarged drawing in the central part ø21±0.8 2±0.5 ø13±0.2 13.5±0.5 No. FJ008-D-R-SD-1.1 TITLE No. SCALE UNIT SOP8J-D-Reel FJ008-D-R-SD-1.1 QTY. mm 2,000 Seiko Instruments Inc. 3.00 -0.2 8 5 +0.3 1 4 0.17±0.05 0.2±0.1 0.65 No. FT008-A-P-SD-1.1 TITLE No. SCALE UNIT TSSOP8-E-PKG Dimensions FT008-A-P-SD-1.1 mm Seiko Instruments Inc. 4.0±0.1 2.0±0.05 ø1.55±0.05 0.3±0.05 8.0±0.1 ø1.55 -0.05 +0.1 (4.4) 6.6 -0.2 +0.4 1 4 8 5 Feed direction No. FT008-E-C-SD-1.0 TITLE No. SCALE UNIT TSSOP8-E-Carrier Tape FT008-E-C-SD-1.0 mm Seiko Instruments Inc. 13.4±1.0 Enlarged drawing in the central part ø21±0.8 2±0.5 ø13±0.5 17.5±1.0 No. FT008-E-R-SD-1.0 TITLE No. SCALE UNIT mm TSSOP8-E-Reel FT008-E-R-SD-1.0 QTY. 3,000 Seiko Instruments Inc. 1 .97±0.03 8 7 6 5 1 0.5 2 3 4 0.08 -0.02 +0.05 0.48±0.02 0.2±0.05 No. PH008-A-P-SD-2.0 TITLE No. SCALE UNIT SNT-8A-A-PKG Dimensions PH008-A-P-SD-2.0 mm Seiko Instruments Inc. ø1.5 -0 +0.1 2.0±0.05 4.0±0.1 0.25±0.05 5° 2.25±0.05 ø0.5±0.1 4.0±0.1 0.65±0.05 4 321 5 6 78 Feed direction No. PH008-A-C-SD-1.0 TITLE No. SCALE UNIT SNT-8A-A-Carrier Tape PH008-A-C-SD-1.0 mm Seiko Instruments Inc. 12.5max. Enlarged drawing in the central part ø13±0.2 9.0±0.3 (60°) (60°) No. PH008-A-R-SD-1.0 TITLE No. SCALE UNIT mm SNT-8A-A-Reel PH008-A-R-SD-1.0 QTY. 5,000 Seiko Instruments Inc. 0.52 2.01 0.52 0.3 0.2 0.3 0.2 0.3 0.2 0.3 Caution Making the wire pattern under the package is possible. However, note that the package may be upraised due to the thickness made by the silk screen printing and of a solder resist on the pattern because this package does not have the standoff. No. PH008-A-L-SD-3.0 TITLE No. SCALE UNIT SNT-8A-A-Land Recommendation PH008-A-L-SD-3.0 mm Seiko Instruments Inc. • • • • • • The information described herein is subject to change without notice. Seiko Instruments Inc. is not responsible for any problems caused by circuits or diagrams described herein whose related industrial properties, patents, or other rights belong to third parties. The application circuit examples explain typical applications of the products, and do not guarantee the success of any specific mass-production design. When the products described herein are regulated products subject to the Wassenaar Arrangement or other agreements, they may not be exported without authorization from the appropriate governmental authority. 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. Although Seiko Instruments Inc. exerts the greatest possible effort to ensure high quality and reliability, the failure or malfunction of semiconductor products may occur. The user of these products should therefore give thorough consideration to safety design, including redundancy, fire-prevention measures, and malfunction prevention, to prevent any accidents, fires, or community damage that may ensue.