unisonic technologies co., ltd lr1108 cmos ic www.unisonic.com.tw 1 of 6 copyright ? 2010 unisonic technologies co., ltd qw-r102-031.c 1a fast ultra low dropout linear regulator ? description the utc lr1108 operate from a +2.5v ~ +7.0v input supply as fast ultra low-dropout linear regul ators. wide output voltage range options are available. the fast response characteristic to make utc lr1108 suitable for low voltage microprocessor application. the low quiescent current operation and low dropout quality caused by the cmos process. the utc lr1108 has ultra low dropout voltage; 300mv at 1a load current typically. the ground pin current is typically 200ua at 1ma load current. error flag: when the output voltage drops 10% below nominal value error flag goes low. output voltage precision: mult iple output voltage options are available and ranging from 1.2v ~ 5. 0v at room temperature with a guaranteed accuracy of 1.5%, and 3.0% when varying line, load and temperature. ? features * ultra low dropout voltage * low ground pin current * 0.04% load regulation * the guaranteed output current is 1a dc * output voltage accuracy 1.5% * error flag indicates output status * low output capacitor required * overtemperature protection and overcurrent protection sot-25 4 5 3 2 1 1 sot-89 ? ordering information pin assignment ordering number package 1 2 3 4 5 packing lr1108g-xx-ab3-a-r sot-89 g o i - - tape reel lr1108g-xx-ab3-c-r sot-89 g i o - - tape reel lr1108g-xx-af5-r sot-25 i g sd error o tape reel
lr1108 cmos ic unisonic technologies co., ltd 2 of 6 www.unisonic.com.tw qw-r102-031.c ? marking information package voltage code pin code pin 1 pin 2 pin 3 pin 4 pin 5 marking a gnd v out v in sot-89 c gnd v in v out sot-25 15 :1.5v 18:1.8v 25:2.5v 2j:2.85v 33:3.3v v in gnd sd error v out spxx g halogen free 1 2 3 45 ? pin description pin description for sot-89 packag e pin code & no a c pin name i/o description 2 3 v out o output voltage 1 1 gnd ground 3 2 v in input supply pin description for sot-25 package pin no pin name i/o description 1 v in input supply 2 gnd ground 3 sd i shutdown lr1108 enable; when the sd pin connects to gnd will shutdown the lr1108; at normal operation, sd must be tied to v dd through a 10k ? pull up resistor. 4 error o error flag, active low; when the output dropout of regulation due to low input voltage, the lr1108 produces a logi c low signal at the error pin. 5 v out o output voltage
lr1108 cmos ic unisonic technologies co., ltd 3 of 6 www.unisonic.com.tw qw-r102-031.c ? block diagram
lr1108 cmos ic unisonic technologies co., ltd 4 of 6 www.unisonic.com.tw qw-r102-031.c ? absolute maximum ratings parameter symbol ratings unit input voltage (operating) , (note 10) 2.5~7.0 v input voltage (survival) v in -0.3~+7.5 v shutdown input voltage v in(shdn) -0.3~v in +0.3 v output voltage (survival), (note 4), (note 5) v out -0.3~+7.5 v i out (survival) short circuit protected maximum voltage for error pin v in +0.3 v maximum operating current (dc) 1 a power dissipation (note 2) p d internally limited junction temperature t j +12 5 c operating temperature t opr -40~+125 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. ? electrical characteristics limits in standard typeface are for t j = 25c, and limits in boldface type apply over the full operating temperature range. (t j = 25c, v in = v o(nom) + 1v, i l = 10 ma, c out = 2.2 f, v sd = v in -0.3v, unless otherwise specified.) parameter symbol test conditions min typ max unit output voltage tolerance (note 6) v out 0 ma i l 1a v out +1 v in 7.0v -1.5 -3 0 +1.5 +3 % output voltage line regulation (note 6) v out v out +1v lr1108 cmos ic unisonic technologies co., ltd 5 of 6 www.unisonic.com.tw qw-r102-031.c ? electrical characteristics(cont.) note 1. conditions for which the device is intended to be fu nctional is indicated by oper ating ratings, but specific performance limits isn?t be guaranteed. to make sure of specifications and test conditions, read electrical characteristics. only for the test conditions listed t he guaranteed specifications can be applied. when the device is not operated under the listed test conditions some performance characteristics may degrade. 2. devices must be derated based on package t hermal resistance at elevated temperatures. 3. the most likely paramet ric norm represents at 25 c. 4. the lr1108 output must be diode- clamped to ground. if used in a dual- supply system where the regulator load is returned to a negative supply. 5. between the v in and v out terminals the output pmos structure contains a diod e. this diode is reverse biased normally. if the voltage at t he output terminal is forced to be hig her than the voltag e at the input terminal this diode will get forward biased. this diode can withstand 1amp of peak current and 200ma of dc current typically. 6. output voltage line regulation is t he change in output voltage from the nom inal value which is due to change in the input line voltage. which is defined as the change in output voltage from the nominal value due to change in load current is output voltage load regulation . the load regulation and line regulation specification include the typical number only. but, the limits for l oad and line regulation are included in the output voltage tolerance specification. 7. error flag hysteresis and threshold are spec ified as regulated output voltage?s percentage. 8. at which the output drops 2% below the normal value dropout vo ltage is defined as the minimum input to output differential voltage. only to output voltages of 2.5v a nd above dropout voltage specification applies. for output voltages below 2.5v, since the minimum input voltage is 2.5v, the drop- out voltage is nothing but the input to output differential. 9. specification has been tested at ? 40c t j 85ccause under shutdown conditi ons the temperature rise of the device is negligible. 10. the minimum operating v in value is equal to [v out(nom) + v dropout ] or 2.5v, just the greater.
lr1108 cmos ic unisonic technologies co., ltd 6 of 6 www.unisonic.com.tw qw-r102-031.c ? 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.
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