low power single op amp LM321MF d e s c r i p t i o n the lm 321 brings performance and economy to low power sot-23-5l sy stem s. with a high unity gain frequency and a guaranteed 0.4v/s slew rate, the quiescent current is only 430a/am plifier (5v). the input com m on m ode range includes ground and therefore the device is able to operate in single supply applications as well as in dual supply applications. it is also capable of com f ortably driving large capacitive loads. the LM321MF is available in the sot-23-5l pack age. overall the LM321MF is a low power, wide supply range perform ance op am p that can be designed into a wide range of applications at an econom ical price without sacrificing valuable board space. features gain-bandwidth product: 1mhz low supply current: 430a low input bias current: 45na wide supply voltage range: +3v to +32v single version of lm358 applica t ions chargers power supplies industrial: controls, instrum e nts desktops com m unications infrastructure tiger electronic co.,ltd
LM321MF block diagram marking informa t ion y ear code data code print model d321: e absolute maximum ra tings (note 1) characteristic va l u e unit supply v o ltage,(v + - v - ) 3 2 v input v o ltage -0.3~+32 v output short circuit to gnd v + 15v anf t a =25 note2 continuous junction t e m p erature (note3) 150 therm a l resistance to am bient ( ja ) 265 operating t e m p erature range -40~+85 s t orage t e m p erature range -65~+150 electrical characteristics (unless otherwise specified: v + =5.0v) param e ter t e st conditions min. ty p . max. unit input of fset v o ltage ta = 2 5 note 4 2 5 m v input bias current ta = 2 5 , i in (+ ) or i in - , v cm =0v note 5 4 5 150 n a input of fset current ta = 2 5 i in (+ ) - i in - v cm =0v 3 3 0 n a input co mm on-mode v o ltage range ta = 2 5 v + =30v note 6 0 v + -1.5 v v + =30v 0 . 6 6 2 supply current over full t e m p erature range , r l = on al l op am ps v + =5v 0 . 4 3 1 . 2 ma lar g e signal v o lt age gain v + =15v ta = 2 5 r l 2k ? for v o =1~1 1v 5 0 1 0 0 v/m v co m m on-m ode rejection ratio dc ta = 2 5 v cm =0~v + -1.5v 7 0 9 0 d b power supply rejection ratio dc ta = 2 5 v + =5~30v 7 5 1 0 0 d b am plifier - to-am p lifier coupling ta = 2 5 f=1~20khz input referred note 7 - 1 2 0 d b
LM321MF source v in(+) =1v,v in(-) =0v,v + =15v,vo=2v, ta=25 20 40 ma v in(-) =1v,v in(+) =0v,v + =15v,vo=2v, ta=25 10 20 ma output current sink v in(-) =1v,v in(+) =0v,v + =15v, vo=200mv,ta=25 12 50 a short circuit to ground v + =15v ta=25 note 2 40 85 ma r l =2k? 26 v v oh v + =30v r l =10k? 27 28 v output voltage swing v ol v + =5v r l =10k? 5 20 mv note 1 absolute maximum ratings indicate limits beyond which damage to the device may occur. operating ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. for guaranteed specifications and the test conditions, see the electrical characteristics. note 2: short circuits from the output to v + can cause excessive heating and eventual destruction. when considering short circuits to ground, the maximum output current is approximately 40ma independent of the magnitude of v + . at values of supply voltage in excess of +15v, continuous short-circuits can exceed the power dissipation ratings and cause eventual destruction. destructive dissipation can result from simultaneous shorts on all amplifiers. note 3: the maximum power dissipation is a function of t j(max) , ja , and ta. the maximum allowable power dissipation at any ambient temperature is p d = (t j(max) - ta)/ ja . all numbers apply for packages soldered directly onto a pc board. note 4: vo=1.4v, rs = 0 ? with v + from 5v to 30v; and over the full input common-mode range (0v to v + -1.5v) at 25c note 5: the direction of the input current is out of the ic due to the pnp input stage. this current is essentially constant, independent of the state of the output so no loading change exists on the input lines. note 6: the input common-mode voltage of either input signal voltage should not be allowed to go negative by more than 0.3v (at 25c). the upper end of them common-mode voltage range is v + -1.5v (at 25c), but either or both inputs can go to +32v without damage, independent of the magnitude of v + . note 7: due to proximity of external components, insure that coupling is not originating via stray capacitance between these external parts. this typically can be detect ed as this type of capacitance increases at higher frequencies.
LM321MF simplified schematic applica t ion circuit
LM321MF typical applica t ions
LM321MF application summary the LM321MF op amp can operate with a single or dual power supply voltage, has true-differential inputs, and remain in the linear mode with an input common-mode voltage of 0 v dc . this amplifier operates over a wide range of power supply voltages, with little change in performance characteristics. at 25 c amplifier operation is possible down to a minimum supply voltage of 3v. large differential input voltages can be easily accommodated and, as input differential voltage protection diodes are not needed, no large input currents result from large differential input voltages. the differential input voltage may be larger than v + without damaging the device. protection should be provided to prevent the input voltages from going negative more than ? 0.3 v dc (at 25c). an input clamp diode with a resistor to the ic input terminal can be used. to reduce the power supply drain, the amplifier has a class a output stage for small signal levels which converts to class b in a large signal mode. this allows the amplifiers to both source and sink large output currents. theref ore both npn and pnp external current boost transistors can be used to extend the power capability of the basic amplifiers. the output voltage needs to raise approximately 1 diode drop above ground to bias the on-chip vertical pnp transistor for output current sinking applications. for ac applications, where the load is capacitively coupled to the output of the amplifier, a resistor should be used, from the output of th e amplifier to ground to increase the class a bias current and to reduce distortion. capacitive loads which are applied directly to the output of the amplifier reduce the loop stability margin. values of 50pf can be acco mmodated using the worst-case non-inverting unity gain connection. large closed loop gains or resistive isolation should be used if large load capacitance must be driven by the amplifier. the bias network of the LM321MF establishes a supply current which is independent of the magnitude of the power supply voltage over the range of from 3 v dc to 30 v dc . output short circuits either to ground or to the positive power supply should be of short time duration. units can be destroyed, not as a result of the short circuit current causing
LM321MF m e tal fusing, but rather due to the large increase in ic chip dissipation which will cause eventual failure due to excessive junction te m p eratures. the larger value of output source current which is available at 25c provides a larger output current capability at elevated tem p eratures than a standard ic op am p. the circuits presented in the section on ty pical applications em phasize operation on only a single power supply voltage. if com p lem e ntary power supplies are available, all of the standard op am p circuits can be used. in general, introducing a pseudo-ground (a bias voltage reference of v + /2) will allow operation above and below this value in single power supply sy stem s. many application circuits are shown which take advantage of the wide input com m on-m ode voltage range which includes ground. in m o st cases, input biasing is not required and input voltages which range to ground can easily be accom m odated. characturistic cur ves (unless otherwise specified: vs=+5v , single supply , t a =25 )
LM321MF
LM321MF outline drawing s o t - 2 3 - 5 l unit:m m
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