unisonic technologies co., ltd usr1051 preliminary linear integrated circuit 3 a synchronous buck regulator ? description the utc usr1051 is a high efficiency, 3a synchronous buck regulator. the utc usr1051 works from 5v to 23v input voltage range, and provides up to 3a of continuous output current with an output voltage adjustable down to 0.8v. the utc usr1051 comes in an exposed pad hsop-8 package and is rated over a -40c~+85c operating ambient temperature range. ? features * synchronous buck * 5v~23v operating input voltage range * high efficiency * internal soft start * output voltage adjustable to 0.8v * 3a continuous output current * cycle-by-cycle current limit * 400khz pwm operation * pre-bias start-up * thermal shutdown * short-circuit protection * exposed pad hsop-8 package hsop-8 ? ordering information ordering number lead free halogen free package packing usr1051l-sh2-t USR1051G-SH2-T hsop-8 tube usr1051l-sh2-r usr1051g-sh2-r hsop-8 tape reel www.unisonic.com.tw 1 of 4 copyright ? 2013 unisonic technologies co., ltd qw-r103-065.b
usr1051 preliminary linear integrated circuit ? pin configuration ? pin description pin no. pin name description 1 pgnd power ground 2 v in supply voltage input 3 agnd analog ground 4 fb feedback input 5 comp external loop compensation pin 6 en enable pin 7 nc no connect pin. 8 nc no connect pin. exposed pad lx switching node ? block diagram comp pgnd lx start up vref current source bias pwm latch ea slope ref_0.8v osc pwm sense dead time control driver driver agnd fb en v in unisonic technologies co., ltd 2 of 4 www.unisonic.com.tw qw-r103-065.b
usr1051 preliminary linear integrated circuit unisonic technologies co., ltd 3 of 4 www.unisonic.com.tw qw-r103-065.b ? absolute maximum rating parameter symbol ratings unit supply voltage v in 23 v lx to agnd -0.7~v in +0.3 v lx to agnd (20ns) -5~22 v en to agnd -0.3~v in +0.3 v fb, ss, comp to agnd -0.3~6.0 v pgnd to agnd -0.3~+0.3 v ambient temperature t a -40~+85 c junction temperature t j +150 c storage temperature t stg -65~+150 c note: absolute maximum ratings are those values beyond which the device could be permanently damaged. absolute maximum ratings are stress ratings only and functional device oper ation is not implied. ? thermal data parameter symbol rating unit junction to ambient (note 2) ja 50 c/w ? recommended operating condiions parameter symbol ratings unit supply voltage v in 5~23 v output voltage v out 0.8~0.85v in v ? electrical characteristics (note 3) (t a =25c, v in =v en =12v, v out =3.3v, unless otherwise specified) parameter symbol test conditions min typ max unit supply voltage v in 5 23 v supply current (quiescent) i in i out =0, v fb =1.2v, v en >2v 3.5 5 ma shutdown supply current i off v en =0v 1 10 a feedback voltage v fb t a =25 c 0.788 0.8 0.812 v load regulation 0.5 % line regulation 1 % feedback voltage input current i fb 200 na off threshold 0.6 v en input threshold v en on threshold 2 v ss time c ss =16nf 2 ms modulator frequency f o 380 450 550 khz maximum duty cycle d max 85 % controllable minimum on time t min 150 ns current sense transconductance 7 a/v error amplifier transconductance 180 a/v protection current limit 3.5 4.5 a t j rising 150 c over-temperature shutdown limit t j falling 100 c notes: 1. devices are inherently esd sensitive, handling precautions are required. human body model rating: 1.5 k? in series with 100pf. 2. the value of ja is measured with t he device mounted on a 1-in 2 fr-4 board with 2oz. copper, in a still air environment with t a =25c. the value in any given applicatio n depends on the user?s specific board design. 3. specification in bold indicate an ambient temperature range of -40 c~+85c. these s pecifications are guaranteed by design.
usr1051 preliminary linear integrated circuit ? 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. unisonic technologies co., ltd 4 of 4 www.unisonic.com.tw qw-r103-065.b
|
