E1217X rev. a2, 12-dec-00 1 (5) 32-khz standard watch cmos ic features 32-khz oscillator 1.3 v to 1.8 v operating-voltage range 180 na typical current consumption voltage regulator integrated capacitors, mask selectable mask options for pad designation, motor period and motor pulse width low resistance outputs for bipolar stepping motor motor fast-test function pad configuration E1217X 2 4 5 6 7 8 1 3 95 9979 figure 1. chip size 1.06 mm x 1.02 mm pad size: 112 m x 112 m pad window: 100 m x 100 m general description the E1217X is an integrated circuit in cmos silicon gate technology for analog watches. it consists of a 32-khz oscillator, frequency dividers down to 1/64 hz, output pulse formers and push-pull motor drivers. for tuning of the crystal, integrated capacitors are provided (selectable mask option). low current consumption and high oscillator stability are enabled by an on-chip voltage regulator. pin symbol function 1, 4 v ss negative supply voltage 5, 6, 8 v dd positive supply voltage 1 to 4 oscin/ oscout oscillator input/output (7/5) or (7/6) mot 1/2 motor drive outputs 1 to 5, 8 reset reset input 1 to 5, 8 test test input/output absolute maximum ratings parameters symbol value unit supply voltage v ss 0.3 to +5 v input voltage range, all inputs v in (v ss 0.3 v ) v in (v dd + 0.3 v) v output short circuit duration indefinite power dissipation (dil package) p tot 125 mw operating ambient temperature range t amb 20 to +70 c storage temperature range t stg 40 to +125 c lead temperature during soldering at 2 mm distance, 10 s t sld 260 c absolute maximum ratings define parameter limits which, if exceeded, may permanently change or damage the device. all inputs and outputs on atmel wireless & microcontrollers' circuits are protected against electrostatic discharges. however, precautions to mini- mize the build-up of electrostatic charges during handling are recommended. the circuit is protected against supply-voltage reversal for typically 5 minutes.
E1217X rev. a2, 12-dec-00 2 (5) functional description voltage regulator an integrated voltage regulator provides the oscillator with a well controlled negative supply voltage v reg . this improves the stability of the oscillator and keeps cur- rent consumption at a minimum. oscillator an oscillator inverter with feedback resistor is provided for generation of the 32768 hz clock frequency. a total capacitance of 24 pf is integrated.this can be selected for c oscout in 2 pf increments via a mask option. frequency divider a 21-bit binary counter is provided, dividing the oscilla- tor frequency down to 1/64 hz. the leading six stages are connected to v dd and v reg , while the remaining 15 stages are connected to v dd and v ss . motor drive output the E1217X contains two push-pull output buffers for driving bipolar stepping motors. during a motor pulse, the n-channel device of one buffer and the p-channel de- vice of the other buffer are activated. the p-channel devices of both buffers are active (figure 3) between two the pulses. cycle time and pulse width can be chosen via a metal- mask option (table1). reset a debounced reset input is provided. connecting the reset input to v dd resets the low order 12 stages of the frequency divider, thus disabling further motor pulses. motor pulses in progress when the reset function is ap- plied are completed. after releasing the reset pad from v dd , the next motor pulse appears with a delay of one half motor cycle on the drive output opposed to the former (figure 4). due to the debounce circuitry on the reset input, v dd must be applied for at least 31.2 ms. during reset the input current is limited to 8 na typically. test a test frequency of 512 hz is output to this pad which can be measured with a high resistance probe (r 10 m c 20 pf). this signal can be used for testing and tuning the oscillator. connecting test to v dd for at least 4 ms changes the motor cycle time from the selected value to the test cycle time (mask options), while the motor pulse width remains unchanged (figure 3). this feature can be used to reduce the amount of time re- quired for testing the mechanical parts of the watch. table 1 motor options cycle time t m = 2, 4, 6, 8, 10, 12, 20, 24, 30, 40, 60, 80, 120 s motor pulse width t m = 0.98 to 14.65 ms in increments of 0.98 ms motor test cycle time t mt = 250, 125, 62.5 ms
E1217X rev. a2, 12-dec-00 3 (5) operating characteristics v dd = 0 v; v ss = 1.55 v; t amb = +25 c; c tr = 15 pf, unless otherwise specified. all voltage levels are measured with reference to v dd . test crystal as specified below. parameters test conditions / pins symbol min. typ. max. unit operating voltage functional test (figure 2) v ss 1.3 1.8 v operating current c oscout = 16 pf, r l = i ss 180 300 na reset input current reset = v dd i r 8 na motor outputs motor output current r l = 2 k , v ss = 1.55 v i m 0.7 ma motor period t m s motor pulse width t m see option list ms motor test period t mt p ms oscillator stability d v ss = 100 mv, c tr = 5 pf, d f/f 0.1 ppm start-up voltage startup within 2 s v st 1.3 v integrated input capacitor c osc in see option list pf integrated output capacitor c oscoutmax = 24 pf c osc out see option list pf note 1: typical parameters represent the statistical mean values test oscin oscout v dd mot2 mot1 reset E1217X v ss c tr r l 1 2 3 4 8 7 6 5 95 9980 figure 2. functional test circuit range of trimmer capacitance: c tr = 5 pf to 30 pf test crystal specification frequency f = 32768 hz series resistance r s = 30 k static capacitance c 0 = 1.5 pf dynamic capacitance c 1 = 3 ff load capacitance c l = 8 pf additional notes 1. it is recommended to connect the quartz case to v dd (by conductive epoxy). 2. capacitive coupling of test to oscin must be minimized by appropriate layout of the pcb to avoid disturbance of the oscillator.
E1217X rev. a2, 12-dec-00 4 (5) t test mot1 mot2 t t m mt m t m t< t tin t > t tin t m /2 95 9981 figure 3. motor drive outputs in normal mode and motor test mot1 mot2 t m t m t m t m (open) reset t< t rin t > t rin t m /2 95 9982 figure 4. motor drive outputs and reset
E1217X rev. a2, 12-dec-00 5 (5) table 2 option list E1217X option motor integrated capacitance *) cycle (t m ) s pulse (t m ) ms test (t mt ) ms c oscin pf c oscout pf pad 1 pad 2 pad 3 pad 4 pad 5 pad 6 pad 7 pad 8 b 2 3.9 125 2 14 v ss test oscin osc- out v dd mot2 mot1 reset e 2 6.8 125 2 14 v ss test oscin osc- out v dd mot2 mot1 reset i 2 7.8 125 2 14 v ss test oscin osc- out v dd mot2 mot1 reset s 2 5.9 125 2 14 v ss test oscin osc- out v dd mot2 mot1 reset va 2 4.9 62.5 4 14 v ss test osc- out oscin v dd mot2 mot1 reset vb 2 4.9 125 4 14 oscin osc- out reset v ss test mot2 mot1 v dd vc 40 5.9 125 2 14 oscin osc- out reset v ss test mot2 mot1 v dd ve 2 5.9 62.5 2 14 osc- out oscin v dd v ss test mot2 mot1 reset vf 2 3.9 62.5 4 14 oscin osc- out reset v ss mot2 vdd mot1 test vh 2 3.9 62.5 4 14 v ss test osc- out oscin v dd mot2 mot1 reset wb 2 4.9 125 4 14 v ss test oscin osc- out v dd mot2 mot1 reset wg 20 5.9 125 2 14 v ss test oscin osc- out v dd mot2 mot1 reset wh 40 6.8 62.5 2 14 v ss test oscin osc- out v dd mot2 mot1 reset *) on-chip stray capacitance included we reserve the right to make changes to improve technical design and may do so without further notice . parameters can vary in different applications. all operating parameters must be validated for each customer application by the customer. should the buyer use atmel wireless & microcontrollers products for any unintended or unauthorized application, the buyer shall indemnify atmel wireless & microcontrollers against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. data sheets can also be retrieved from the internet: http://www.atmelwm.com atmel germany gmbh, p.o.b. 3535, d-74025 heilbronn, germany telephone: 49 (0)7131 67 2594, fax number: 49 (0)7131 67 2423
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