SM8580 Nippon_Precision_Circuits America, SM8580 Datasheet
SM8580
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SM8580 Summary of contents
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... OVERVIEW The SM8580AM is a real-time clock IC based on a 32.768kHz crystal oscillator, which features a 4-bit parallel interface for communication with an external microcontroller. It comprises second-counter to year-counter clock and calendar circuits that feature automatic leap-year adjust- ment up to year 2099, alarm and timer interrupt functions, clock counter change detect functions, ±30-second correction function, time error correction function, and built-in temperature sensor ...
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... PACKAGE DIMENSIONS (Unit: mm) 24-pin SSOP 10.05 0.20 10.20 0.30 0.8 0.10 BLOCK DIAGRAM XT XTN AIRQN TIRQN FOUT FCON WRN RDN CE0N CE1 SM8580AM 0.36 0.10 0. Digital Trimming C OSC Divider D Controller Clock and Calendar Counter Alarm Register Interrupt Control Timer Register FOUT FOUT Register Control Control Register ...
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... Read strobe input. Data can be read from SM8580AM when RDN is LOW and WRN is HIGH. An error will occur if both RDN and WRN are simultaneously LOW. Ground Write strobe input. Data can be written to SM8580AM when RDN is HIGH and WRN is LOW. An error will occur if both RDN and WRN are simultaneously LOW. Data bus input/outputs. ...
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... FOUT Output and SM8580AM Access Relationship CE0N CE1 HIGH LOW LOW LOW HIGH HIGH LOW HIGH SPECIFICATIONS Absolute Maximum Ratings Parameter Supply voltage range Input voltage range Output voltage range Storage temperature range Recommended Operating Conditions Parameter ...
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... V V OL3 DD LOW-level output voltage OL4 DD LOW-level output voltage OL5 DD Output leakage current D3, AIRQN, TIRQN, FOUT SM8580AM Condition = 5V CE0N = RDN = WRN = CE1 = FCON = AIRQN = TIRQN = FOUT = VTEMP output OFF (TEMP bit = ° ...
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... Frequency voltage characteristic Frequency accuracy Input capacitance Output capacitance AC Characteristics (1) = −40 to 85°C unless otherwise noted Parameter FOUT duty Oscillator failure detection time SM8580AM Symbol Condition ADD DATA = 30kΩ 10pF) unless otherwise noted I L Symbol ...
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... RD output set time RD output floating Output hold time Write cycle time Chip select time Address valid to end-of-write Address setup time Address hold time Write pulsewidth Input data set time Input data hold time SM8580AM = 0.5V , outputs ACC ACS ARD ...
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... CE1 RDN Data write CE control CE0N* CE1 WRN control CE0N CE1 WRN When writing data, CE0N or WRN should be held HIGH level while the address changes. SM8580AM ACC OH t ACS t t CLZ CHZ t ACS t t ...
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... VTEMP, and b = difference between the measured values at temperatures of −40 and 85°C VTEMP(V) = ∆V ÷ ∆I 3. Output resistance R [Ω SM8580A SM8580AM Condition Ta = 25°C, VSS reference output voltage 2.7 to 5.5V, VTEMP 25°C –40°C ≤ Ta ≤ 85° 2 – ...
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... Parameter Supply voltage falling edge CE setup time Supply voltage fall time Supply voltage rise time Supply voltage rising edge CE hold time 1. Before switching the supply, confirm that the chip enable CE1 is LOW and that SM8580AM is deselected CLK CE1 SM8580AM ...
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... CTEMP CDT_ON FOUT divider set C # FD2 register FOUT frequency set register E Alarm control TEST TEMP Bank Bank F Control register SEL1 SEL0 SM8580AM Bank 2 (digital correction, timer registers) Bit 1 Bit 0 Address Register Digital correction registers – – ...
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... STOP bit I When set to 1, the clock 32Hz frequency divider counter stops and is reset. When set to 0, the clock restarts. SM8580AM Bit 3 Bit 2 TEST TEMP Bank SEL1 Bank SEL0 BUSY/ADJ bit I This bit functions as a BUSY function in read mode, and as an ADJ function in write mode. ...
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... If the FOUT source clock frequency is ≤ 1Hz, the cycle changes. If the FOUT source clock frequency is ≥ 32Hz, the cycle does not change the FOUT source clock frequency is ≤ 1Hz, the timer is stopped. If the FOUT source clock frequency is ≥ 32Hz, the timer operates. SM8580AM Function Clock Timer ...
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... Address Registers are 4 digits forming the western I calendar year. SM8580AM Register Bit 3 8 Second registers FOS 8 Minute registers 8 Hour registers Hour register contents are values expressed in 24- I hour mode. by writing 0 to FOS not affected by the func- tion of other bits ...
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... Day-of-week alarm bits (register 6) The day-of-week register contains values repre- I senting the day of the week as shown in the fol- lowing table. SM8580AM Register Bit 3 Alarm control remains 1 until reset by writing 0 to AF. A logic 1 cannot be written to AF. ...
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... The TIRQN output is high imped- ance when TIE is set to 0. TI/TP bit (level/periodic interrupt mode select bit) I Sets the timer interrupt signal output mode. The SM8580AM supports two timer function modes. Timer source clock set register (register 8) Bank Address ...
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... WRN rising edge that sets the TE bit, shown in the timing diagram below. Also, when WRN pin D3 pin Timer source clock Timer SM8580AM Register Bit 3 8 Timer counter set registers 128 8 128 ...
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... Frequency divider FD2 FD1 FD0 ratio 1/6 SM8580AM Register Bit 3 CE1 control CTEMP Function operation tables I CE1 pin × LOW HIGH LOW HIGH CE1 pin × LOW HIGH LOW HIGH Register Bit 3 FOUT divider set register ...
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... SM8580AM Register Bit 3 DT3 Digital correction registers DT_ON Correction value calculation I • Positive correction (leading time) [DT6:0] = correction ÷ 3.05 (with decimal round-off) Example: for correction of 192.15ppm [DT6:0] = 192.15 ÷ 3. • Negative correction (lagging time) [DT6:0] = 128 + correction ÷ ...
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... When TIE is 1 and a timer interrupt event occurs (TF bit is set to 1), TIRQN goes LOW. When TIE is 0, how- ever, TIRQN high-impedance state. "1" TIE bit TIRQN pin TF bit SM8580AM "1" "1" *No output while AIE bit is "0". "0" "0" ...
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... TD0 and TD1. Source CLK TIRQN pin Auto return time ( TD1 TD0 SM8580AM "1" t RTN Auto-return Setting TF bit to "0" RTN Interrupt cycle Source clock Auto-return time (t 4096Hz 0.122ms 64Hz 7 ...
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... Acquire the current weekday setting from bank 0 register 6, add 1 to the current value (except in Using the Temperature Sensor The SM8580AM temperature sensor can be used to monitor the surrounding temperature. The tempera- ture sensor information can then be used to adjust the clock for any temperature variations in the oscillator frequency which affect the accuracy of the clock ...
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... Customers are requested not to export or re-export, directly or indirectly, the Products to any country or any entity not in compliance with or in violation of the national export administration laws, treaties, orders and regulations. Customers are requested appropriately take steps to obtain required permissions or approvals from appropriate government agencies. SM8580AM NIPPON PRECISION CIRCUITS INC. 4-3, Fukuzumi 2-chome, Koto-ku, ...