View MIC2601_3100233.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

MIC2601/2 1.2a, 1.2mhz/2mhz wide input range integrated switch boost regulator general description the MIC2601/2 is a 1.2mhz/2mhz, pwm dc/dc boost switching regulator available in a 2mm x 2mm mlf ? package. high power density is achieved with the MIC2601/2?s internal 40v/1.2a switch, allowing it to power large loads in a tiny footprint. the MIC2601/2 implements constant frequency 1.2mhz/2mhz pwm current mode control. the MIC2601/2 offers internal compensation that provides excellent transient response and output regulation performance. the high frequency operation saves board space by allowing small, low-profile exter nal components. the fixed frequency pwm scheme also reduces spurious switching noise and ripple to the input power source. soft start reduces in rush current and is programmable via external capacitor. the MIC2601/2 is available in a 2mm x 2mm 8-pin mlf ? leadless package. both devices have an output over- voltage protection feature. the MIC2601/2 has an operating junction temperature range of ?40 c to +125 c. data sheets and support documentation can be found on micrel?s web site at: www.micrel.com. features ? wide input voltage range: 4.5v to 20v ? output voltage adjustable to 40v ? 1.2a switch current ? MIC2601 operates at 1.2mhz ? mic2602 operates at 2mhz ? stable with small size ceramic capacitors ? high efficiency ? programmable soft start ? <10a shutdown current ? uvlo ? output over-voltage protection ? over temperature shutdown ? 8-pin 2mm x 2mm mlf ? package ? ?40 c to +125 c junction temperature range applications ? multimedia stb/antenna ? broadband communications ? tft-lcd bias supplies ? bias supply ? positive output regulators ? sepic converters ? dsl applications ? local boost regulators ___________________________________________________________________________________________________________ typical application 10h 6.65k MIC2601/2 vin v in = 12v v out 18v, 500ma en sw fb pgnd 2.2f 10f ss 0.1f vdd agnd 0.1f 0 10 20 30 40 50 60 70 80 90 100 0 load current (ma) 18 v out efficienc y 0 100 200 300 400 500 600 700 800 12v in 8v in mlf and micro leadframe are registered trademarks of amkor technology, inc. micrel inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel +1 ( 408 ) 944-0800 ? fax + 1 (408) 474-1000 ? http://www.micrel.com september 2009 m9999-090909-a
micrel, inc. MIC2601/2 september 2009 2 m9999-090909-a ordering information part number marking code (1) frequency output over voltage protection temperature range package (2) lead finish MIC2601yml rd1 1.2mhz 40v ?40 to +125c 8-pin 2mm x 2mm mlf ? pb-free mic2602yml re1 2mhz 40v ?40 to +125c 8-pin 2mm x 2mm mlf ? pb-free notes 1. overbar ( ) symbol my not be to scale. 2. mlf ? is a green rohs compliant package. lead fini sh is nipdau. mold compound is halogen free. pin configuration vin vdd en agnd pgnd sw fb ss 1 2 3 4 8 7 6 5 8-pin 2mm x 2mm mlf ? (ml) pin description pin number pin name pin function 1 vin supply (input): 4. 5v to 20v input voltage. 2 vdd internal regulator. vdd should be connected to vin when vin 7v. 3 en enable (input): logic high enables regulator. logic low shuts down regulator. 4 agnd analog ground 5 ss soft start 6 fb feedback (input): 1.25v output voltage sense node. v out = 1.25v ( 1 + r1/r2) 7 sw switch node (input): inte rnal power bipolar collector. 8 pgnd power ground ep gnd ground (return): exposed backside pad. internally fused to agnd and pgnd pins.
micrel, inc. MIC2601/2 september 2009 3 m9999-090909-a absolute maximum ratings (1) supply voltage (v in ) .......................................................22v switch voltage (v sw )....................................... ?0.3v to 40v enable voltage (v en )......................................... ?0.3v to v in fb voltage (v fb )...............................................................6v ambient storage temperature (t s ) ...........?65c to +150c lead temperature (sol dering 10se c) ......................... 260c esd rati ng..................................................................... 2kv operating ratings (2) supply voltage (v in ).......................................... 4.5v to 20v enable voltage (v en )............................................ 0v to 20v junction temperature (t j ) ........................ ?40c to +125c junction thermal resistance 2mm x 2mm mlf-8 ( ja ) ...................................90c/w 2mm x 2mm mlf-8 ( jc ) ...................................45c/w electrical characteristics (3) t a = 25c, v in = v en = 12v; unless otherwise noted. bold values indicate ?40c ? t j ? +125c. symbol parameter condition min typ max units v in input voltage range 4.5 20 v v dd internal regulated voltage note 4 6.0 v v ulvo under-voltage lockout for v dd 1.8 2.1 2.4 v i q quiescent current v fb = 2v (not switching) 4.2 6 ma i sd shutdown current v en = 0v, note 5 0.08 2 a (2%) 1.235 1.26 1.285 v v fb feedback voltage (3%) (over temperature) 1.222 1.298 v i fb feedback input current v fb = 1.25v ?550 na line regulation 8v ? v in ? 14v, v out = 18v 0.04 1 % load regulation 5ma ? i out ? 400ma, v out = 18v, note 6 0.1 % ss r internal soft start resistor 15 k d max maximum duty cycle MIC2601 mic2602 85 80 % % i sw switch current limit note 6 1.2 1.7 a v sw switch saturation voltage i sw = 1.2a 500 mv i sw switch leakage current v en = 0v, v sw = 18v 0.01 5 a v en enable threshold turn on turn off 1.5 0.3 v v i en enable pin current v en = 12v 18.5 40 a oscillator frequency (MIC2601) 1.02 1.12 1.38 mhz f sw oscillator frequency (mic2602) 1.7 1.92 2.3 mhz v ovp output over-voltage protection 15% over programmed v out (rising) 10 15 20 % 150 c t j over-temperature threshold shutdown hysteresis 10 c notes: 1. absolute maximum ratings indicate limits beyond which damage to the component may occur. electrical specifications do not apply when operating the device outside of its operating ratings. the maximum a llowable power dissipation is a function of the maximum junctio n temperature, t j(max) , the junction-to-ambient thermal resistance, ja , and the ambient temperature, t a . the maximum allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. 2. the device is not guaranteed to function outside its operating rating. 3. specification for packaged product only. 4. connect v dd pin to v in pin when v in ? 7v. 5. i sd = i vin . 6. guaranteed by design.
micrel, inc. MIC2601/2 september 2009 4 m9999-090909-a typical characteristics 0 1 2 3 4 5 6 7 0 246 81 01 21 41 61 8 input voltage (v) quiescent current vs. input voltage no switching fb pin @ 2v 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2 4.3 4.4 4.5 quiescent current vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) no switching fb pin @ 2v 85 86 87 88 89 90 91 46 81 01 21 41 61 82 0 input voltage (v) max duty cycle vs. input voltage en = v in 80 82 84 86 88 90 92 94 96 98 100 max duty cycle vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) en = 20v v in = 20v 0 270 540 810 1080 1350 1620 1890 2160 2430 2700 46 81 01 21 41 61 82 0 input voltage (v) switch saturation voltage vs. input voltage ?0.1a ?0.2a 0 270 540 810 1080 1350 1620 1890 2160 2430 2700 switch current (a) ?4v ?5v ?0.3a ?0.4a ?0.5a ?0.6a ?0.7a ?0.8a ?0.9a ?1.0a ?1.1a ?1.2a ?1.3a ?1.4a ?1.5a ?1.6a ?1.7a ?6v ?7v ?8v ?9v ?10v ?12v ?15v ?20v switch saturation voltage vs. switch current 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 46 81 01 21 41 61 82 0 input voltage (v) switch current limit vs. input voltage en = v in 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 switch current limit vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) v in = 12v 0 0.5 1.0 1.5 2.0 v sat vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) i sw = current limit i sw = 850ma i sw = 500ma i sw = 1200ma 1.240 1.245 1.250 1.255 1.260 1.265 1.270 feedback voltage vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) v in = 12v load = 100ma 1.250 1.255 1.260 1.265 1.270 1.275 1.280 1.285 1.290 enable threshold on vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) v in = 12v 15 16 17 18 19 20 21 22 23 24 25 enable current vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) en = 0v v in = 12v
micrel, inc. MIC2601/2 september 2009 5 m9999-090909-a typical characteristics 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 46 81 01 21 41 61 82 0 input voltage (v) frequency vs. input voltage mic2602 MIC2601 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 frequency vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) mic2602 MIC2601 0 10 20 30 40 50 60 70 80 90 100 0 load current (ma) 18v out efficiency 0 100 200 300 400 500 600 700 800 12v in 8v in 40 50 60 70 80 90 100 load current (ma) 18v out efficiency 20 30 40 50 60 70 80 12v in 90 100 010 8v in 4.5v in 0.070 0.073 0.076 0.079 0.082 0.085 0.088 0.091 0.094 0.097 0.100 shutdown current vs. temperature -40 -20 0 20 40 60 80 100 120 temperature (c) en = 0v v in = 12v 0 100 200 300 400 500 600 700 800 900 thermal derating -40 -20 0 20 40 60 80 100 120 temperature (c) v in = 12v v out = 18v
micrel, inc. MIC2601/2 september 2009 6 m9999-090909-a functional characteristics
micrel, inc. MIC2601/2 september 2009 7 m9999-090909-a functional diagram pgnd ca ovp cl thermal uvlo bandgap ramp generator 1.2 / 2mhz oscillator sw en vdd vin 1.25v pwm cmp ovp cmp fb regulator bandgap ss osc + + s r osc ea agnd figure 1. MIC2601/2 block diagram
micrel, inc. MIC2601/2 september 2009 8 m9999-090909-a functional description the MIC2601/2 is a constant frequency, pwm current mode boost regulator. the block diagram is shown in figure 1. the MIC2601/2 is composed of an oscillator, slope compensation ramp generator, current amplifier, g m error amplifier, pwm generator, and a 1.2a bipolar output transistor. the oscillator generates a 1.2mhz/2mhz clock. the cloc k?s two functions are to trigger the pwm generator that turns on the output transistor and to reset the slope compensation ramp generator. the current amplifier is used to measure the switch current by amplifying the voltage signal from the internal sense resistor. the output of the current amplifier is summed with the output of the slope compensation ramp generator. this summed current-loop signal is fed to one of the inputs of the pwm generator. the g m error amplifier measures the feedback voltage through the external feedback resistors and amplifies the error between the detected signal and the 1.25v reference voltage. the output of the gm error amplifier provides the voltage-loop signal that is fed to the other input of the pwm generator. when the current-loop signal exceeds the voltage-loop signal, the pwm generator turns off the bipolar output transistor. the next clock period initiates the next switching cycle, maintaining the constant frequency current-mode pwm control. pin description vin vin provides power to the mosfets for the switch mode regulator section. due to the high switching speeds, a 2.2f capacitor is recommended close to vin and the power ground (pgnd) pin for bypassing. please refer to layout recommendations. vdd the vdd pin supplies the power to the internal power to the control and reference circuitry. the vdd is powered from vin. a small 0.1f capacitor is recommended for bypassing. en the enable pin provides a logic level control of the output. in the off state, suppl y current of the device is greatly reduced (typically <0.1 a). also, in the off state, the output drive is placed in a "tri-stated" condition, where bipolar output transistor is in an ?off? or non- conducting state. do not drive the enable pin above the supply voltage. ss the ss pin is the soft start pin which allows the monotonic buildup of output when the MIC2601/2 comes up during turn on. the ss pin gives the designer the flexibility to have a desired soft start by placing a capacitor ss to ground. a 0.1f capacitor is used for in the circuit. fb the feedback pin (fb) provides the control path to control the output. for fixed output controller output is directly connected to feedback (fb) pin. sw the switch (sw) pin connects directly to the inductor and provides the switching current necessary to operate in pwm mode. due to the high speed switching and high voltage associated with this pin, the switch node should be routed away from sensitive nodes. pgnd power ground (pgnd) is the ground path for the high current pwm mode. the current loop for the power ground should be as small as possible and separate from the analog ground (agnd) loop. refer to the layout considerations for more details. agnd analog ground (agnd) is the ground path for the biasing and control circuitry. the current loop for the signal ground should be separate from the power ground (pgnd) loop. refer to the lay out considerations for more details.
micrel, inc. MIC2601/2 september 2009 9 m9999-090909-a application information dc-to-dc pwm boost conversion the MIC2601/2 is a constant frequency boost converter. it operates by taking a dc input voltage and regulating a higher dc output voltage. figure 2 shows a typical circuit. boost regulation is achieved by turning on an internal switch, which draws current through the inductor (l1). when the switch turns off, the inductor?s magnetic field collapses, causing the current to be discharged into the output capacitor through an external schottky diode (d1). voltage regulation is achieved through pulse-width modulation (pwm). 10h 6.65k MIC2601/2 vin v in v out en sw fb pgnd 2.2f 10f ss 0.1f vdd agnd 0.1f gnd gnd figure 2. typical application circuit duty cycle considerations duty cycle refers to the switch on-to-off time ratio and can be calculated as follows for a boost regulator: out in v v d ?= 1 the duty cycle required for voltage conversion should be less than the maximum duty cycle of 85%. also, in light load conditions, where the i nput voltage is close to the output voltage, the minimum duty cycle can cause pulse skipping. this is due to the energy stored in the inductor causing the output to over shoot slightly over the regulated output voltage. during the next cycle, the error amplifier detects the output as being high and skips the following pulse. this effect can be reduced by increasing the minimum load or by increasing the inductor value. increasing the inductor value reduces peak current, which in turn reduces energy transfer in each cycle. overvoltage protection for the MIC2601/2 there is an over voltage protection function. if the output voltage overshoots the set voltage by 15% when feedback is high during input higher than output, turn on, load transients, line transients, load disconnection etc. the MIC2601/2 ovp ckt will shut the switch off saving itself and other sensitive circuitry downstream. component selection inductor inductor selection is a balance between efficiency, stability, cost, size, and rated current. for most applications, a 10h is the recommended inductor value; it is usually a good balance between these considerations. large inductance values reduce the peak-to-peak ripple current, affecting efficiency. this has an effect of reducing both the dc losses and the transition losses. there is also a secondary effect of an inductor?s dc resistance (dcr ). the dcr of an inductor will be higher for more induct ance in the same package size. this is due to the longer windings required for an increase in inductance. since the majority of input current (minus the MIC2601 operating current) is passed through the inductor, higher dcr inductors will reduce efficiency. to maintain stabilit y, increasing inductor size will have to be met with an increase in output capacitance. this is due to the unavoidable ?right half plane zero? effect for the continuous current boost converter topology. the frequency at which the right half plane zero occurs can be calculated as follows: ( ) o o il vd frhpz ??? ? = 2 2 the right half plane zero has the undesirable effect of increasing gain, while decreasing phase. this requires that the loop gain is rolled off before this has significant effect on the total loop response. this can be accomplished by either r educing inductance (increasing rhpz frequency) or increasing the output capacitor value (decreasing loop gain). output capacitor output capacitor selection is also a trade-off between performance, size, and cost. increasing output capacitance will lead to an improved transient response, but also an increase in size and cost. x5r or x7r dielectric ceramic capacitors are recommended for designs with the MIC2601/2. y5v values may be used, but to offset their tolerance over temperature, more capacitance is required. diode selection the MIC2601/2 requires an external diode for operation. a schottky diode is recommended for most applications due to their lower forward voltage drop and reverse recovery time. ensure the diode selected can deliver the peak inductor current and the maximum reverse voltage is rated greater than the output voltage. input capacitor a minimum 2.2 f ceramic capacitor is recommended for designing with the MIC2601/2. increasing input capacitance will improve performance and greater noise
micrel, inc. MIC2601/2 september 2009 10 m9999-090909-a immunity on the source. the input capacitor should be as close as possible to the inductor and the MIC2601, with short traces for good noise performance. feedback resistors the MIC2601/2 utilizes a feedback pin to compare the output to an internal reference. the output voltage is adjusted by selecting the appr opriate feedback resistor network values. the r2 resistor value must be less than or equal to 1k ? (r2 1k ? ). the desired output voltage can be calculated as follows: ? 1 ? ? 1 2 1 r r vv ref out where v ref is equal to 1.25v.
micrel, inc. MIC2601/2 september 2009 11 m9999-090909-a c1 2.2f/16v 1 2 21 d1 b360a ss 5 agnd 4 vdd 2 en 3 vin 1 fb 6 sw 7 8 u1 MIC2601/2 pgnd j1 vin 12v j2 gnd j3 en r3 10k c2 0.1f/50v c3 0.1f/50v l1 10h r1 6.65k r2 c4 4.7f/50v c5 4.7f/50v j4 vo 18v j5 gnd bill of materials item part number manufacturer description qty. grm21br71c225ka12l murata (1) c1 0805yc225mat avx (2) capacitor, 2.2f, 16v, x7r, size 0805 1 vj0603y104kxaat vishay (3) 06035c104mat avx (2) capacitor, 0.1f, 50v, x7r, size 0603 c2, c3 grm188r71c104ka01d murata (1) capacitor, 0.1f, 16v, x7r, size 0603 2 c4, c5 grm31cr71h475ka12l murata (1) capacitor, 4.71f, 50v, x7r, size 1206 2 ss3p6-e3 vishay (3) d1 b360a diodes (4) 3a, 60v schottky diode 1 l1 lqh55dn100m03 murata (1) 10h, 1700ma 1 r1 crcw06036k65fkea vishay dale (3) resistor, 6.65k, 1%, 1/10w, size 0603 1 r2 crcw06034990fkea vishay dale (3) resistor, 499 ? , 1%, 1/10w, size 0603 1 r3 crcw060310k0fkea vishay dale (3) resistor, 10k, 1%, 1/10w, size 0603 1 MIC2601yml 1.2a, 1.2mhz wide range integrated switch boost regulator u1 mic2602yml micrel, inc. (5) 1.2a, 2mhz wide range integrated switch boost regulator 1 notes: 1. murata: www.murata.com 2. avx: www.avx.com 3. vishay: www.vishay.com 4. murata: www.diodes.com 5. micrel, inc.: www.micrel.com
micrel, inc. MIC2601/2 september 2009 12 m9999-090909-a pcb layout recommendations top layer bottom layer
micrel, inc. MIC2601/2 september 2009 13 m9999-090909-a package information 8-pin 2mm x 2mm mlf ? (ml) micrel, inc. 2180 fortune drive san jose, ca 95131 usa tel +1 (408) 944-0800 fax +1 (408) 474-1000 web http://www.micrel.com the information furnished by micrel in this data sheet is belie ved to be accurate and reliable. however, no responsibility is a ssumed by micrel for its use. micrel reserves the right to change circuitry and specific ations at any time without notification to the customer. micrel products are not designed or authorized for use as components in life suppor t appliances, devices or systems where malfu nction of a product reasonably be expected to result in pers onal injury. life support devices or system s are devices or systems that (a) are in tended for surgical impla into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significan t injury to the user. a purchaser?s use or sale of micrel produc ts for use in life support app liances, devices or systems is a purchaser?s own risk and purchaser agrees to fully indemnify micrel for any damages resulting from such use or sale. can nt ? 2008 micrel, incorporated.

▲Up To Search▲

Price & Availability of MIC2601

	To Download MIC2601 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .