general description the max8863t/s/r and max8864t/s/r low-dropout linear regulators operate from a +2.5v to +6.5v input range and deliver up to 120ma. a pmos pass transistor allows the low, 80a supply current to remain independent of load, making these devices ideal for battery-operated portable equipment such as cellular phones, cordless phones, and modems. the devices feature dual mode? operation: their output voltage is preset (at 3.15v for the t versions, 2.84v for the s versions, or 2.80v for the r versions) or can be adjusted with an external resistor divider. other features include low-power shutdown, short-circuit protection, thermal shutdown protection, and reverse battery protection. the max8864 also includes an auto-discharge function, which actively discharges the output voltage to ground when the device is placed in shutdown mode. both devices come in a miniature 5-pin sot23 package. applications cordless telephones pcs telephones cellular telephones pcmcia cards modems hand-held instruments palmtop computers electronic planners beneits and features low cost low, 55mv dropout voltage at 50ma i out low, 68a no-load supply current low, 80a operating supply current (even in dropout) low, 350v rms output noise miniature external components thermal overload protection output current limit reverse battery protection dual mode operation: fixed or adjustable (1.25v to 6.5v) output low-power shutdown 19-0466; rev 6; 5/16 dual mode is a trademark of maxim integrated products, inc. *alternate marking information: cy_ _ = max8863t, cz_ _ = max8863s, da_ _ = max8864t, db_ _ = max8864s +denotes a lead(pb)-free/rohs-compliant package. part temp range pin-package max8863 teuk+t -40c to +85c 5 sot23 max8863tmuk/pr3+t -55c to +125c 5 sot23 max8863seuk+t -40c to +85c 5 sot23 max8863reuk+t -40c to +85c 5 sot23 max8864 teuk+t -40c to +85c 5 sot23 max8864seuk+t -40c to +85c 5 sot23 max8864reuk+t -40c to +85c 5 sot23 max8863max8864 out gnd set in shdn c out 1f c in 1f battery outputvoltage sot23 top view gnd out in 1 + 5 set shdn max8863max8864 23 4 max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators typical operating circuit pin coniguration ordering information downloaded from: http:///
v in to gnd ................................................................. -7v to +7v output short-circuit duration ........................................... infinite set to gnd ............................................................ -0.3v to +7v shdn to gnd ............................................................ -7v to +7v shdn to in .............................................................. -7v to +0.3v out to gnd ............................................... -0.3v to (v in + 0.3v) continuous power dissipation (multilayer board, t a = +70c) sot23 (3.9mw/c above +70c) ............................ 312.6mw operating temperature range ........................... -40c to +85c operating temperature range (max8863tmuk/pr3+) .................... -55c to +125c junction temperature ...................................................... +150c storage temperature range ............................ -65c to +150c lead temperature (soldering, 10s) ................................. +300c soldering temperature (reflow) ....................................... +260c sot23 junction-to-ambient thermal resistance ( ja ) ..... 255.9c/w junction-to-case thermal resistance ( jc ) ............... 81c/w (note 1) (v in = +3.6v, v gnd = 0v, t a = t min to t max , unless otherwise noted. typical values are at t a = +25c.) (note 2) parameter symbol conditions min typ max units input voltage (note 3) v in 2.5 6.5 v output voltage v out 0ma i out 50ma, set = gnd max886_t 3.05 3.15 3.25 v max886_s 2.75 2.84 2.93 max886_r 2.70 2.80 2.88 adjustable output voltage range (note 4) v out v set 6.5 v maximum output current 120 ma current limit (note 5) i lim 280 ma ground pin current i q set = gnd i load = 0ma 68 150 a i load = 50ma 80 dropout voltage (note 6) i out = 1ma 1.1 mv i out = 50ma 55 120 line regulation ?v lnr v in = 2.5v to 6.5v, set tied to out, i out = 1ma -0.15 0 +0.15 %/v load regulation ?v ldr i out = 0ma to 50ma set = gnd 0.011 0.040 %/ma set tied to out 0.006 output voltage noise 10hz to 1mhz c out = 1f 350 v rms c out = 100f 220 shutdown shdn input threshold v ih 2.0 v v il 0.4 max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators www.maximintegrated.com maxim integrated 2 note 1: package thermal resistances were obtained using the method described in jedec specification jesd51- 7, using a four-layer board. for detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial . absolute maximum ratings stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. these are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. package thermal characteristicselectrical characteristics downloaded from: http:///
(v in = +3.6v, v gnd = 0v, t a = t min to t max , unless otherwise noted. typical values are at t a = +25c.) (note 2) note 2: limits are 100% production tested at t a = +25c. limits over the operating temperature range are guaranteed through cor - relation using statistical quality control (sqc) methods. note 3: guaranteed by line regulation test. note 4: adjustable mode only. note 5: not tested. for design purposes, the current limit should be considered 120ma minimum to 420ma maxim um. note 6: the dropout voltage is defined as (v in - v out ) when v out is 100mv below the value of v out for v in = v out +2v. (v in = +3.6v, c in = 1f, c out = 1f, t a = +25c, max886_t, unless otherwise noted.) parameter symbol conditions min typ max units shdn input bias current i shdn v shdn = v in t a = +25c 0 100 na t a = t max 0.05 shutdown supply current i qshdn v out = 0v t a = +25c 0.0001 1 a t a = t max 0.02 shutdown discharge resistance (max8864) 300 ? set input set reference voltage (note 4) v set v in = 2.5v to 6.5v, i out = 1ma t a = +25c 1.225 1.25 1.275 v e temp range 1.215 1.25 1.285 m temp range 1.205 1.25 1.285 set input leakage current (note 4) i set v set = 1.3v t a = +25c 0.015 2.5 na t a = t max 0.5 thermal protection thermal shutdown temperature t shdn 170 c thermal shutdown hysteresis ?t shdn 20 c 100 50 0 20 60 100 supply current vs. load current 60 90 max8863/4-02 load current (ma) supply current (a) 40 80 10 30 70 50 90 8070 9555 8575 65 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0 1 2 4 6 output voltage vs. input voltage max8863/4-03 input voltage (v) output voltage (v) 3 5 no load 3.00 3.05 3.10 3.15 3.20 3.25 3.30 0 20 60 100 output voltage vs. load current max8863/4-01 load current (ma) output voltage (v) 40 80 10 30 70 50 90 max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators www.maximintegrated.com maxim integrated 3 electrical characteristics (continued) typical operating characteristics downloaded from: http:///
(v in = +3.6v, c in = 1f, c out = 1f, t a = +25c, max886_t, unless otherwise noted.) 0 10 20 30 40 50 60 70 80 90 0 1 2 4 6 supply current vs. input voltage max8863/4-04 input voltage (v) 3 5 supply current (a) i load = 0ma i load = 50ma 3.00 3.05 3.10 3.15 3.20 3.25 3.30 0 20 -20 60 100 output voltage vs. temperature max8863/4-05 temperature (c) output voltage (v) 40 -40 80 i load = 50ma 0 10 20 30 40 50 60 70 80 90 100 100 80 60 40 20 0 -20 -40 supply current vs. temperature max8863/4-06 temperature (c) supply current (a) i load = 50ma 0 20 40 60 80 100 120 140 0 20 60 100 dropout voltage vs. load current max8863/4-07 load current (ma) dropout voltage (mv) 40 80 10 30 70 50 90 t a = +85c t a = +25c t a = -40c 1 10 max8863/4-08 frequency (khz) psrr (db) 7060 50 40 30 20 10 0 100 1000 0.1 0.01 v out = 3.15v r l = 100w c out = 10f c out = 1f power-supply rejection ratio vs. frequency 10 0.01 0.1 10 100 1 1000 output spectral noise density vs. frequency 0.10 max8863/64-8a frequency (khz) output spectral noise density (v/hz) 1 r l = 50 ? c out = 1f c out = 100f 1000 0.01 0 50 60 70 80 90 10 20 30 40 100 region of stable c out esr vs. load current 0.1 max8863/64-8b load current (ma) c out esr ( ? ) 1 10 100 internal feedback stable region c out = 1f external feedback i load = 50ma, v out is ac coupled output noise dc to 1mhz v out 1ms/div maxim integrated 4 www.maximintegrated.com max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators typical operating characteristics (continued) downloaded from: http:///
(v in = +3.6v, c in = 1f, c out = 1f, t a = +25c, max886_t, unless otherwise noted.) i load = 50ma, v out is ac coupled line transient 3.16v v out 3.15v 3.14v 4.6v 3.6v v in 50s/div i load = 0ma to 50ma, c in = 10f, v out is ac coupled load transient 3.16v v out 3.15v 3.14v i load 10s/div v in = v out + 0.2v, i load = 0ma to 50ma, c in = 10f, v out is ac coupled load transient i load 3.16v v out 3.15v 3.14v 10s/div v in = v out + 0.1v, i load = 0ma to 50ma, c in = 10f, v out is ac coupled load transient 0ma 50ma 10s/div 3.16v v out 3.15v3.14v i load no load max8864 shutdown (no load) 0v v shdn 4v v out 0v2v 2v 500s/div i load = 50ma max8864 shutdown 0v v shdn v out 4v 2v 0v2v 200s/div maxim integrated 5 www.maximintegrated.com max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators typical operating characteristics (continued) downloaded from: http:///
detailed description the max8863/max8864 are low-dropout, low-quiescent - current linear regulators designed primarily for battery - powered applications. they supply an adjustable 1.25v to 6.5v output or a preselected 2.80v (max886_r), 2.84v (max886_s), or 3.15v (max886_t) output for load currents up to 120ma. as illustrated in figure 1 , these devices consist of a 1.25v reference, error amplifier, mosfet driver, p-channel pass transistor, dual mode? comparator, and internal feedback voltage divider. the 1.25v bandgap reference is connected to the error amplifiers inverting input. the error amplifier compares this reference with the selected feedback voltage and amplifies the difference. the mosfet driver reads the error signal and applies the appropriate drive to the p-channel pass transistor. if the feedback voltage is lower than the reference, the pass-transistor gate is pulled lower, allowing more current to pass and increasing the output voltage. if the feedback voltage is too high, the pass-transistor gate is pulled up, allowing less current to pass to the output. the output voltage is fed back through either an internal resistor voltage divider connected to the out pin, or an external resistor network connected to the set pin. the dual mode comparator examines the set voltage and selects the feedback path. if set is below 60mv, internal feedback is used and the output voltage is regulated to the preset output voltage. additional blocks include a current limiter, reverse battery protection, thermal sensor, and shutdown logic. figure 1. functional diagram pin name function 1 shdn active-low shutdown input. a logic low reduces the supply current to 0.1na. on the max8864, a logic low also causes the output voltage to discharge to gnd. connect to in for normal operation. 2 gnd ground. this pin also functions as a heatsink. solder to large pads or the circuit board ground plan e to maximize thermal dissipation. 3 in regulator input. supply voltage can range from +2.5v to +6.5v. bypass with 1f to gnd (see capacitor selection and regulator stability ). 4 out regulator output. fixed or adjustable from +1.25v to +6.5v. sources up to 120ma. bypass with a 1f, < 0.2 typical esr capacitor to gnd. 5 set feedback input for setting the output voltage. connect to gnd to set the output voltage to the prese t 2.80v (max886_r), 2.84v (max886_s), or 3.15v (max886_t). connect to an external resistor- divider for adjustable-output operation. shutdown logic error amp 1.25v ref p n * out set dual-modecomparator 60mv * auto-discharge, max8864 only gnd in shdn max8863 max8864 mos driver with i limit thermal sensor reverse battery protection max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators www.maximintegrated.com maxim integrated 6 pin description downloaded from: http:///
internal p-channel pass transistor the max8863/max8864 feature a 1.1 typical pmosfet pass transistor. this provides several advantages over similar designs using pnp pass transistors, including longer battery life. the pmosfet requires no base drive current, which reduces quiescent current considerably. pnp-based regulators waste considerable amounts of current in dropout when the pass transistor saturates. they also use high base-drive currents under large loads. the max8863/max8864 do not suffer from these problems, and consume only 80a of quiescent current, whether in dropout, light load, or heavy load applications (see typical operating characteristics ). output voltage selection the max8863/max8864 feature dual mode operation: they operate in either a preset voltage mode or an adjustable mode. in preset voltage mode, internal, trimmed feedback resistors set the max886_r output to 2.80v, the max886_s output to 2.84v, and the max886_t output to 3.15v. select this mode by connecting set to ground. in adjustable mode, select an output between 1.25v and 6.5v using two external resistors connected as a voltage divider to set ( figure 2 ). the output voltage is set by the following equation: v out = v set (1 + r1 / r2) where v set = 1.25v. to simplify resistor selection: out set v r1 r2 1 v ?? = ? ???? choose r2 = 100k to optimize power consumption, accuracy, and high-frequency power-supply rejection. the total current through the external resistive feedback and load resistors should not be less than 10a. since the v set tolerance is typically less than 25mv, the output can be set using fixed resistors instead of trim pots. connect a 10pf to 25pf capacitor across r1 to compensate for layout-induced parasitic capacitances. in preset voltage mode, impedances between set and ground should be less than 100k. otherwise, spurious conditions could cause the voltage at set to exceed the 60mv dual mode threshold. shutdown a low input on the shdn pin shuts down the max8863/ max8864. in shutdown mode, the pass transistor, control circuit, reference, and all biases are turned off, reducing the supply current to typically 0.1na. connect shdn to in for normal operation. the max8864 output voltage is actively discharged to ground when the part is placed in shutdown (see typical operating characteristics ). current limit the max8863/max8864 include a current limiter that monitors and controls the pass transistors gate voltage, estimating the output current and limiting it to about 280ma. for design purposes, the current limit should be considered 120ma (min) to 420ma (max). the output can be shorted to ground for an indefinite time period without damaging the part. thermal overload protection thermal overload protection limits total power dissipation in the max8863/max8864. when the junction temperature exceeds t j = +170c, the thermal sensor sends a signal to the shutdown logic, turning off the pass transistor and allowing the ic to cool. the thermal sensor will turn the pass transistor on again after the ics junction temperature typically cools by 20c, resulting in a pulsed output during continuous thermal overload conditions. thermal overload protection is designed to protect the max8863/max8864 in the event of fault conditions. stressing the device with high load currents and high input-output differential voltages (which result in die temperatures above +125c) may cause a momentary overshoot (2% to 8% for 200ms) when the load is completely removed. this can be remedied by raising the minimum load current from 0a (+125c) to 100a (+150c). for continuous operation, do not exceed the absolute maximum junction temperature rating of t j = +150c. figure 2. adjustable output using external feedback resistors max8863max8864 out set gnd in shdn c out 1f c in 1f battery outputvoltage r1 20pf r2 r l max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators www.maximintegrated.com maxim integrated 7 downloaded from: http:///
operating region and power dissipation maximum power dissipation of the max8863/max8864 depends on the thermal resistance of the case and circuit board, the temperature difference between the die junction and ambient air, and the rate of air flow. the power dissipation across the device is p = i out (v in - v out ). the resulting maximum power dissipation is: p max = (t j - t a ) / ja where (t j - t a ) is the temperature difference between the max8863/max8864 die junction and the surrounding air, and ja is the thermal resistance of the chosen package to the surrounding air. the gnd pin of the max8863/max8864 performs the dual function of providing an electrical connection to ground and channeling heat away. connect the gnd pin to ground using a large pad or ground plane. reverse battery protection the max8863/max8864 have a unique protection scheme that limits the reverse supply current to less than 1ma when either v in or v shdn falls below ground. the circuitry monitors the polarity of these two pins, disconnecting the internal circuitry and parasitic diodes when the battery is reversed. this feature prevents the device from overheating and damaging the battery. v in > 5.5v minimum load current when operating the max8863/max8864 with an input voltage above 5.5v, a minimum load current of 20a is required to maintain regulation in preset voltage mode. when setting the output with external resistors, the minimum current through the external feedback resistors and load must be 30a. applications information capacitor selection and regulator stability normally, use a 1f capacitor on the input and a 1f capacitor on the output of the max8863/max8864. larger input capacitor values and lower esr provide better supply-noise rejection and transient response. a higher-value input capacitor (10f) may be necessary if large, fast transients are anticipated and the device is located several inches from the power source. improve load-transient response, stability, and power-supply rejection by using large output capacitors. for stable operation over the full temperature range, with load currents up to 120ma, a minimum of 1f is recommended. noise the max8863/max8864 exhibit 350v rms noise during normal operation. when using the max8863/max8864 in applications that include analog-to-digital converters of greater than 12 bits, consider the adcs power-supply rejection specifications (see the output noise dc to 1mhz photo in the typical operating characteristics ). power-supply rejection and operation from sources other than batteries the max8863/max8864 are designed to deliver low dropout voltages and low quiescent currents in battery - powered systems. power-supply rejection is 62db at low frequencies and rolls off above 300hz. as the frequency increases above 20khz, the output capacitor is the major contributor to the rejection of power-supply noise (see the power-supply rejection ratio vs. ripple frequency graph in the typical operating characteristics ). when operating from sources other than batteries, improve supply-noise rejection and transient response by increasing the values of the input and output capacitors, and using passive filtering techniques (see the supply and load-transient responses in the typical operating characteristics ). load transient considerations the max8863/max8864 load-transient response graphs (see typical operating characteristics ) show two components of the output response: a dc shift of the output voltage due to the different load currents, and the transient response. typical overshoot for step changes in the load current from 0ma to 50ma is 12mv. increasing the output capacitors value and decreasing its esr attenuates transient spikes. max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators www.maximintegrated.com maxim integrated 8 downloaded from: http:///
input-output (dropout) voltage a regulators minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. in battery-powered systems, this will determine the useful end-of-life battery voltage. because the max8863/ max8864 use a pmosfet pass transistor, their dropout voltage is a function of r ds(on) multiplied by the load current (see electrical characteristics ). package type package code outline no. land pattern no. 5 sot23 u5+1 21-0057 90-0174 max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators www.maximintegrated.com maxim integrated 9 package information for the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages . note that a +, #, or - in the package code indicates rohs status only. package drawings may show a different suffix character, but the drawing pertains to the package regardless of rohs status. downloaded from: http:///
revision number revision date description pages changed 3 5/11 added lead-free designation and updated continuous power dissipation and ja specs 1, 2 4 7/12 corrected units for toc 7 4 5 4/13 updated ordering information and electrical characteristics tables 1, 3 6 5/16 updating ordering information table 1 maxim integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim integrated product. no circuit patent licenses are implied. maxim integrated reserves the right to change the circuitry and speciications without n otice at any time. the parametric values (min and max limits) shown in the electrical characteristics table are guaranteed. other parametric values quoted in this data sheet are provided for guidance. maxim integrated and the maxim integrated logo are trademarks of maxim integrated products, inc. ? 2016 maxim integrated products, inc. 10 max8863t/s/r, max8864t/s/r low-dropout, 120ma linear regulators revision history for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim integrateds website at www.maximintegrated.com. downloaded from: http:///
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