unisonic technologies co., ltd ud36061 preliminary cmos ic www.unisonic.com.tw 1 of 6 copyright ? 2016 unisonic technologies co., ltd qw-r103-120.a 0.6a, 36v, 2mhz step-down converter ? description the utc ud36061 is a high frequency (2mhz) step-down switching regulator with integrated internal high-side high voltage power mosfet. it regulates input voltages from 3.3v to 36v down to an output voltage as low as 0.8v, and supplies 0.6a highly efficient output with current mode control for fast loop response. in shutdown mode the supply current drops to 3 a, it allows use in battery-powered applications. high power conversion efficiency over a wide load range is achieved by scaling down the switching frequency at light load condition to reduce the switching and gate driving losses. the converter uses internal n-channel mosfet switches to step-down the input vo ltage to the regulated output voltage. since the high side mosfet requires a gate voltage greater than the input voltage, a boost capacitor connected between sw and bst is needed to drive the high side gate. the boost capacitor is charged from the internal 5v rail when sw is low. frequency fold-back helps prevent inductor current runaway during start-up. thermal shutdown pr ovides reliable, fault-tolerant operation. ? applications * high voltage power conversion * automotive systems * industrial power systems * distributed power systems * battery powered systems ? features sot-26 1 2 3 4 5 6 * wide 3.3v ~ 36v o perating input range * 500m ? internal power mosfets * 230 a operating quiescent current * > 90% efficiency * 2mhz fixed switching frequency * internally compensated * internal soft-start * adjustable output voltage from 0.8v to 0.8v in * precision current limit wit hout current sensing resistor * stable with ceramic output capacitors * 3 a low shutdown supply current
ud36061 preliminary cmos ic unisonic technologies co., ltd 2 of 6 www.unisonic.com.tw qw-r103-120.a ? ordering information ordering number package packing UD36061G-AG6-R sot-26 tape reel ? marking
ud36061 preliminary cmos ic unisonic technologies co., ltd 3 of 6 www.unisonic.com.tw qw-r103-120.a ? pin configuration ? pin description pin no. pin name description 1 bst high-side gate drive boost input. bst supplies the drive for the high-side n-channel mosfet switch. connect a 0.1 f or greater capacitor from sw to bst to power the high side switch. 2 gnd ground. 3 fb feedback input. fb senses the output volt age to regulate that voltage. drive fb with a resistive voltage divider from the output voltage. the feedback threshold is 0.8v. 4 en enable input. pulling this pin below the specified threshold shuts the chip down. pulling it above the specified threshold enab les the chip. floating this pin shuts the chip down. 5 v in power input. in supplies the power to the ic, as well as the step-down converter switches. drive in with a 3.3v to 36v power source. bypass in to gnd with a suitably large capacitor to eliminat e noise on the input to the ic. 6 sw power switching output. sw is the switching node that supplies power to the output. connect the output lc filter from sw to the output load. a low v f schottky diode to ground is required closed to this pin to reduce switching spikes. ? block diagram 5 refference uvlo logic oscilator 2mhz internal regulator isw isw ss 0.8v 0.5ms ss ss fb v in bst sw gnd en 1 6 4 3 2
ud36061 preliminary cmos ic unisonic technologies co., ltd 4 of 6 www.unisonic.com.tw qw-r103-120.a ? absolute maximum rating (note1, 2) parameter symbol ratings unit supply input voltage v in -0.3v ~ +40 v sw voltage v sw -0.3v ~ v in +0.3 v bst to sw v bst -0.3 ~ 6.0 v all other pins voltage -0.3v to + 5.0 v power dissipation t a =25c (note 4) p d 0.57 w maximum junction temperature range t j +150 c storage temperature range t stg -65 ~ 150 c ? thermal data (note 3) parameter symbol ratings unit junction to ambient ja 220 /w junction to case jc 110 /w ? recommended operating conditions (note 2) parameter symbol ratings unit supply input voltage v in +3.3v ~ +36v v output voltage v out 0.8v ~ 0.8v in v operating junction temperature range t j -40 ~ +125 c operating ambient te mperature range t a -40 ~ +85 c notes: 1. exceeding these ratings may damage the device. 2. the device is not guaranteed to functi on outside of its operating conditions. 3. measured on jesd 51-7, 4-layer pcb. 4. the maximum allowable power dissipation is a f unction of the maximum junction temperature t j (max), the junction-to-ambient thermal resistance ja , and the ambient temperature t a . the maximum allowable continuous power dissipation at any am bient temperature is calculated by p d (max.) = ( t j (max.) -t a )/ ja exceeding the maximum allowable power regulator wi ll go into thermal shutdown. internal thermal shutdown. circuitry protects t he device from permanent damage.
ud36061 preliminary cmos ic unisonic technologies co., ltd 5 of 6 www.unisonic.com.tw qw-r103-120.a ? electrical characteristics (v in = 12v, v en = 2v, t a = +25c, unless otherwise specified.) parameter symbol test conditions min typ max unit 4.0v Q v in Q 36v 794 mv feedback voltage v fb 3.3v Q v in Q 4.0v 794 mv hs switch-on resistance (note 1, 2) hs rds-on v bst -v sw = 5v 500 m ? hs switch leakage current isw lkg v en =0v, v sw =0v 0.1 1 ua current limit (note 1, 2) i limit 1.0 a comp to current sense trans-conductance g cs 3 a/v minimum operating v in voltage 3.3 v v in uvlo up threshold 2.7 3.2 v v in uvlo hysteresis 0.4 v soft-start time t ss fb from 0 to 1.8v 0.5 msec oscillation frequency f sw 1600 2000 2400 khz minimum on time (note 1) t on_min 100 ns shutdown current i shdn v en = 0v. 3 15 a quiescent current i q v fb = 0.9v, no load 130 a thermal shutdown (note 1) t sd 150 c en input high voltage v en_h v en rising 1.4 1.55 1.7 v en shutdown threshold voltage hysteresis 300 mv notes: 1. guaranteed by design. 2. not tested in production and guaranteed by over-temperature correlation.
ud36061 preliminary cmos ic unisonic technologies co., ltd 6 of 6 www.unisonic.com.tw qw-r103-120.a ? typical application circuit utc assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all utc products described or contained herein. utc products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. the information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice.
|
