general description the max7376 silicon oscillator with reset, is a replace- ment for ceramic resonators, crystals, crystal oscillator modules, and discrete reset circuits. the max7376 pro- vides the primary clock source and reset function for microcontrollers in 3v, 3.3v, and 5v applications. the max7376 features a factory-programmed high-speed oscillator and a microprocessor (?) power-on-reset (por) supervisor. unlike typical crystal and ceramic resonator oscillator circuits, the max7376 is resistant to vibration and emi. the high-output-drive current and absence of high- impedance nodes make the oscillator less susceptible to dirty or humid operating conditions. with a wide operating temperature range as standard, the max7376 is a good choice for demanding home appliance, industrial, and automotive environments. the max7376 is available in factory-programmed fre- quencies from 32.768khz to 10mhz. see table 2 for standard frequencies and contact the factory for cus- tom frequencies. the max7376 is available in a 5-pin sot23 package. refer to the max7382 data sheet for frequencies 10mhz. the max7376 standard operating tempera- ture range is -40 c to +125 c. see the applications information section for the extended operating temper- ature range. applications white goods automotive consumer products appliances and controls handheld products portable equipment microcontroller (?) systems features ? 2.7v to 5.5v operation ? accurate oscillator: 600khz to 10mhz or 32khz ? reset output holds the ? in reset for 100? after clock startup ? ?0ma clock output drive capability ? 2% initial accuracy ? ?0ppm/? temperature coefficient ? 50% duty cycle ? 5ns output rise and fall time ? low jitter: 160ps p-p ) at 8mhz (no pll) ? 3ma operating current (8mhz) ? 13? operating current (32khz) ? -40? to +125? temperature range max7376 silicon oscillator with reset output ________________________________________________________________ maxim integrated products 1 gnd v cc rst/rst 15 e.c. clock max7376 sot23 top view 2 3 4 pin configuration ordering information 19-3475; rev 0; 10/04 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. standard version is shown in bold. the first letter after the part number designates the reset output option. insert the letter corresponding to the desired reset threshold level from table 1 in the next position. insert the two- letter code from table 2 in the remaining two positions for the desired frequency range. see table 3 for standard part numbers. part temp range pin- package reset output m a x7 3 7 6c _ _ _ - t -40 c to +125 c5 sot23-5 open drain m ax 7376a_ _ _- t -40 c to +125 c5 sot23-5 active high push-pull m ax 7376b_ _ _- t -40 c to +125 c5 sot23-5 active low push-pull typical application circuit appears at end of data sheet.
max7376 silicon oscillator with reset output 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics (v cc = 2.7v to 5.5v, t a = -40? to +125 c, unless otherwise noted. typical values are at v cc = 5v and t a = +25 c.) (note 1) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v cc to gnd .............................................................-0.3v to +6v all other pins to gnd ................................-0.3v to (v cc + 0.3v) clock current ................................................................ 10ma continuous power dissipation (t a = +70 c) 5-pin sot23 (derate 7.1mw/ c above +70 c) ...................571mw (u5 - 2) operating temperature range .........................-40 c to +135 c junction temperature .....................................................+150 c storage temperature range.............................-60 c to +150 c lead temperature (soldering, 10s).................................+300 c parameter symbol conditions min typ max units operating supply voltage v cc 2.7 5.5 v f clock = 8mhz, no load 3 5 ma operating supply current i cc f clock = 32.768khz, no load 13 25 ? clock output minimum operating voltage 1.65 v v cc = 4.5v, i source = 9ma v cc - 0.4 output high voltage v oh v cc = 2.7v, i source = 2.5ma v cc - 0.4 v v cc = 4.5v, i sink = 20ma 0.4 output low voltage v ol v cc = 2.7v, i sink = 10ma 0.4 v v cc = 5v, t a = +25 c (note 2) -2 +2 initial frequency accuracy f clock v cc = 2.7v to 5.5v, t a = +25? -4 +4 % frequency temperature sensitivity (note 3) 50 325 ppm/ o c v cc = 5v, t a = +25 c (note 2) 32.440 32.768 33.096 initial frequency accuracy (32.768khz) f clock v cc = 2.7v to 5.5v, t a = +25? 31.785 33.751 khz frequency temperature sensitivity 32.768khz (note 3) 50 325 ppm/ o c clock output duty cycle 43 50 57 % clock output jitter observation of 8mhz output for 20s using a 500mhz oscilloscope 160 ps p - p clock output rise time t r 10% to 90% 5 ns clock output fall time t f 90% to 10% 5 ns
max7376 silicon oscillator with reset output _______________________________________________________________________________________ 3 note 1: all parameters are tested at t a = +25?. specifications over temperature are guaranteed by design. note 2: the frequency is determined by part number selection. see table 3. note 3: guaranteed by design. not production tested. electrical characteristics (continued) (v cc = 2.7v to 5.5v, t a = -40? to +125 c, unless otherwise noted. typical values are at v cc = 5v and t a = +25 c.) (note 1) parameter symbol conditions min typ max units rst/ rst output t a = +25? v th - 2% v th + 2% reset threshold v th+ v cc rising t a = -40? to +125? v th - 5% v th + 5% v reset hysteresis v thys v hyst = {(v th+ ) - ( v th- )}/(v th- ) x 100% 2.0 % por delay v cc rising from 0v to (v th + 200mv) in 1? 100 ? v cc = 4.5v, i source = 9ma v cc - 0.4 output high voltage v oh v cc = 2.7v, i source = 2.5ma v cc - 0.4 v v cc = 4.5v, i sink = 20ma 0.4 output low voltage v ol v cc = 2.7v, i sink = 10ma 0.4 v leakage current i leak v cc = 5.5v, v rst = 5.5v, open drain 1 a 45 47 46 49 53 54 52 51 48 50 55 -55 -5 20 45 70 -30 95 120 duty cycle vs. temperature max7376 toc01 temperature ( c) duty cycle (%) clock = 4mhz 45 47 46 49 53 54 52 51 48 50 55 4.3 4.6 4.9 5.2 5.5 duty cycle vs. supply voltage max7376 toc02 supply voltage (v) duty cycle (%) clock = 4mhz 0.5 0.7 0.6 0.9 1.3 1.4 1.2 1.1 0.8 1.0 1.5 -55 -5 20 45 70 -30 95 120 supply current vs. temperature max7376 toc03 temperature ( c) supply current (ma) clock = 4mhz t ypical operating characteristics (v cc = 5v, t a = +25 c, unless otherwise noted.)
max7376 silicon oscillator with reset output 4 _______________________________________________________________________________________ 3.90 3.94 3.92 3.98 4.06 4.08 4.04 4.02 3.96 4.00 4.10 4.3 4.6 4.9 5.2 5.5 frequency vs. supply voltage max7376 toc05 supply voltage (v) frequency (mhz) clock = 4mhz 3.90 3.94 3.92 3.98 4.06 4.08 4.04 4.02 3.96 4.00 4.10 -55 -5 20 45 70 -30 95 120 frequency vs. temperature max7376 toc06 temperature ( c) frequency (mhz) clock = 4mhz clock output waveform (c l = 10pf) max7376 toc07 clock 40ns/div f = 4mhz, c l = 10pf clock output waveform (c l = 50pf) max7376 toc08 clock 40ns/div f = 4mhz, c l = 50pf clock output waveform (c l = 100pf) max7376 toc09 clock 40ns/div f = 4mhz, c l = 100pf 1000 10 0 200 400 600 800 1000 maximum transient duration vs. reset threshold max7376 toc10 reset threshold overdrive (mv) maximum transient duration ( s) 100 reset = 4.29v reset occurs above the curve t ypical operating characteristics (continued) (v cc = 5v, t a = +25 c, unless otherwise noted.) 0.5 0.7 0.6 0.9 1.3 1.4 1.2 1.1 0.8 1.0 1.5 4.3 4.6 4.9 5.2 5.5 supply current vs. supply voltage max7376 toc04 supply voltage (v) supply current (ma) clock = 4mhz
max7376 silicon oscillator with reset output _______________________________________________________________________________________ 5 detailed description the max7376 is a clock generator with integrated reset for ?s and uarts in 3v, 3.3v, and 5v applications (figure 1). the max7376 is a replacement for crystal oscillator modules, crystals, or ceramic resonators and a system-reset ic. the clock frequency is factory trimmed to specific values. a variety of popular stan- dard frequencies are available (table 2). no external components are required for setting or adjusting the frequency. supply voltage the max7376 has been designed for use in systems with nominal supply voltages of 3v, 3.3v, or 5v and is specified for operation with supply voltages in the 2.7v to 5.5v range. see the absolute maximum ratings sec- tion for limit values of power-supply and pin voltages. oscillator the clock output is a push-pull configuration and is capable of driving a ground-connected 500 ? or a posi- tive-supply-connected 250 ? load to within 400mv of either supply rail. the clock output remains stable over the full operating voltage range and does not generate short output cycles during either power-on or power-off. a typical startup characteristic is shown in the typical operating characteristics . applications information interfacing to a c clock input the max7376 clock output is a push-pull, cmos, logic output that directly drives any ? or c clock input. there are no impedance-matching issues when using the max7376. the max7376 is not sensitive to its posi- tion on the board and it does not need to be placed right next to the ?. refer to the c data sheet for clock-input compatibility with external clock signals. the max7376 requires no biasing components or load capacitance. when using the max7376 to retrofit a crystal oscillator, remove all biasing components from the oscillator input. rst reset output options the max7376 is available with three reset output stage options: push-pull with active-low output, push-pull with active-high output, and open drain with active-low out- put. the rst output is asserted when the monitored input (v cc ) drops below the internal v th- threshold and remains asserted for 100 s after the monitored input exceeds the internal v th+ threshold. the open-drain rst output requires an external pullup resistor. output jitter the max7376? jitter performance is given in the electrical characteristics table as a peak-to-peak value obtained by observing the output of the max7376 for 20s with a 500mhz oscilloscope. jitter values are approximately proportional to the period of the output frequency of the device. thus, a 4mhz part has approximately twice the jitter value of an 8mhz part. the jitter performance of clock sources degrades in the presence of mechanical and electrical interference. pin description pin name function 1 clock push-pull clock output 2 gnd ground 3 rst reset output. see the rst reset output options section for more details. 4v cc positive supply voltage. bypass v cc to gnd with a 0.1? capacitor. 5 e.c. must be externally connected to v cc logic 600khz to 10mhz por mux rst/rst clock bias_v v cc max7376 figure 1. functional diagram
max7376 silicon oscillator with reset output 6 _______________________________________________________________________________________ max7376 clock osc1 osc2 c rst v cc supply voltage e.c. rst/rst t ypical application circuit the max7376 is relatively immune to vibration, shock, and emi influences, and thus provides a considerably more robust clock source than crystal or ceramic res- onator-based oscillator circuits. initial power-up and operation the clock starts up within 30? (typ) after v cc has risen above the reset threshold. the reset output remains asserted for 100? after the reset threshold is reached. extended temperature operation the max7376 was tested to +135? during product characterization and shown to function normally at this temperature (see the typical operating characteristics ). however, production test and qualifi- cation is only performed from -40? to +125? at this time. contact the factory if operation outside this range is required. power-supply considerations the max7376 operates with a 2.7v and 5.5v power- supply voltage. good power-supply decoupling is needed to maintain the power-supply rejection perfor- mance of the max7376. bypass v cc to gnd with a 0.1? surface-mount ceramic capacitor. mount the bypass capacitor as close to the device as possible. if possible, mount the max7376 close to the ?? decou- pling capacitor so that additional decoupling is not required. a larger value bypass capacitor is recom- mended if the max7376 is to operate with a large capacitive load. use a bypass capacitor value of at least 1000 times that of the output load capacitance. suffix reset threshold (v) r 2.57 m 4.29 suffix standard frequency (mhz) aa 32.768khz mg 1 ok 1.8432 qt 3.39545 qw 3.6864 rd 4 rh 4.1943 tp 8 table 1. standard reset threshold levels table 2. standard frequencies for all other reset threshold options, contact factory. for all other reset threshold options, contact factory.
max7376 silicon oscillator with reset output _______________________________________________________________________________________ 7 chip information transistor count: 2027 process: bicmos part pin-package reset threshold (v) frequency (hz) top mark max7376craa 5 sot23 2.57 32.768k aeuz max7376crmg 5 sot23 2.57 1m aeun max7376crok 5 sot23 2.57 1.8432m aeuj MAX7376CRQT 5 sot23 2.57 3.39545m aett max7376crqw 5 sot23 2.57 3.6864m aetu max7376crrd 5 sot23 2.57 4m aetv max7376crrh 5 sot23 2.57 4.1943m aetw max7376crtp 5 sot23 2.57 8m aesf max7376cmmg 5 sot23 4.29 1m aeum max7376cmok 5 sot23 4.29 1.8432m aeui max7376cmqt 5 sot23 4.29 3.39545m aesh max7376cmqw 5 sot23 4.29 3.6864m aetp max7376cmrd 5 sot23 4.29 4m aesj max7376cmrh 5 sot23 4.29 4.1943m aetr max7376cmtp 5 sot23 4.29 8m aets table 3. standard part numbers
max7376 silicon oscillator with reset output maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2004 maxim integrated products printed usa is a registered trademark of maxim integrated products. maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 2004 maxim integrated products printed usa is a registered trademark of maxim integrated products. package information (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation go to www.maxim-ic.com/packages .) sot-23 5l .eps e 1 1 21-0057 package ? outline, ? sot-23, ? 5l
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