View AX3112_5528055.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

1/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 pwm control 3a step-down converter ? general description AX3112 consists of step-down switching regulator with pwm control. the device includes a reference voltage source, oscillation circuit, error amplifier, internal pmos and etc. AX3112 provides low-ripple power, hi gh efficiency, and excellent transient characteristics. the pwm control circuit is abl e to the duty ratio linearly forms 0 up to 100%. with the addition of an internal p-channel power mos, a coil, capacitors, and a diode connected externally, these ics can function as step-down switching regulators. they serve as ideal power supply units for port able devices when coupled with the sop-8l-ep package, providing such outstanding features as low current consumption. since this converter can accommodate an input voltage up to 40v, it is also suitable for the operation via an ac adapter. ? features - input voltage 8v to 40v - adjustable version output vo ltage range from 3.3v to 38v - duty ratio 0% to 100% pwm control - oscillation frequency 100k/350 khz - enable and auto restart function. - thermal shutdown function / internal ovp. - short circuit protect (scp). - built-in internal sw p-channel mos. - sop-8l-ep pb-free package. www.datasheet.net/ datasheet pdf - http://www..co.kr/
2/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? block diagram ? pin assignment the package of AX3112 is sop-8l-ep; the pin assignment is given by: ( top view ) 1 2 3 4 8 7 6 5 en/ct vgate sop C 8l C ep vcc vss fb sense2 sw sense1 sw AX3112 name description en/ct on/off and auto restart control vss gnd pin vgate driver gate clamping pin. the pin must connect a 0.1uf capacitor to vcc vcc operating voltage input sw switch pin. connect external inductor and diode here sense1 current sense input1 sense2 current sense input2 fb feedback pin ? order/marking information order information top marking package type es: sop-8l-ep AX3112 xxxx packing blank : tube a : taping frequency blank : 100khz a: 350khz a ax 3 logo part number id code: internal ww: 01~52 year: 10=2010 11=2011 blank: AX3112 a: AX3112a yy wwx 1 12 www.datasheet.net/ datasheet pdf - http://www..co.kr/
3/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? absolute maximum ratings (at t a = 25c) characteristics symbol rating unit vcc pin voltage v cc v ss - 0.3 to v ss + 45 v feedback pin voltage v fb v ss - 0.3 to 38 v en/ct, ovp pin voltage v ss - 0.3 to 6 v sense1,sense2 pin voltage v ss - 0.3 to 38 v switch pin voltage v sw v ss - 0.3 to v cc + 0.3 v power dissipation pd (t j ? t a )/ ja w storage temperature range t st -40 to +165 c operating temperature range t op -20 to +125 c operating supply voltage v op +8 to +40 v output current i out 0 to 3 a thermal resistance from junction to case jc 15 c/w thermal resistance from junction to ambient ja 40 c/w note : ja is measured with the pcb copper are (need connect to exposed pad) of approximately 1 in 2 (multi-layer). www.datasheet.net/ datasheet pdf - http://www..co.kr/
4/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? electrical characteristics (v cc =12v, t a =25c, unless otherwise specified) characteristics symbol conditions min typ max units fb v fb i out =10ma 1.08 1.10 1.12 v under voltage lockout u vlo falling - 6 - v uvlo hysteresis - - 0.8 - v ovp detect voltage v ovp fb floating - 1.250 - v line regulation - v cc =10 ~ 40v - 0.5 1 % load regulation - i out =0 ~ 1a, r sense = 140m ? - 0.3 0.6% mv quiescent current i ccq v fb > 1.2v - 3 6 ma oscillator frequency f osc AX3112 80 100 120 khz AX3112a 280 350 420 max. duty cycle (on) dc force driver on v fb = 0.7v - 100 - % min. duty cycle (off) force driver of f v fb = 1.2v - 0 - internal mosfet r dson r dson v cc =12v, v fb = 0.7v - 110 170 m ? sense voltage v sense v sense1 -v sense2 110 125 140 mv sense voltage hysteresis v sense-h - 45 - mv en/ct pin logic input threshold voltage v en shutdown mode - 0.3 v v ct auto restart, v fb <0.4v 0.5 1.5 en/ct pin current i en/ct-c charge current - -32 - ua en/ct pin current i en/ct-d discharge current - 1.5 - ua thermal shutdown temp t sd - 160 - c thermal shutdown hysteresis t sh - 40 - c www.datasheet.net/ datasheet pdf - http://www..co.kr/
5/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? application circuit (1) al capacitor vcc=10~36v vout=5.0v/2.05a c4 0.1u c9 0.1u c1 10n u1 AX3112 / a 1 2 3 4 5 6 7 8 en/ct vss vgate vcc sw sense1 sense2 fb r-sense 50mr r3 39k c8 0.1u l1 r4 11k c2 option c5 0.1u d1 b340a c3 470u c7 470u ) r4 r3 + (1 1.1v = v out l1 recommend value (v in =10~36v ,v out =5v) version AX3112 AX3112a l1 value (h) 66u 22u (2) mlcc vout=5.0v/2.05a vcc=10~36v c6 22u c7 22u c3 22u c2 option u1 AX3112a 1 2 3 4 5 6 7 8 en/ct vss vgate vcc sw sense1 sense2 fb c1 10n c5 0.1u c4 0.1u c9 0.1u l1 22uh d1 b340a r-sense 50mr c8 0.1u r4 11k r3 39k r1 470r/option www.datasheet.net/ datasheet pdf - http://www..co.kr/
6/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? function descriptions sense1/2 the current limit sense pin, if v sense1 -v sense2 R 125mv, the over current is happened that it can turn-off driver cycle by cycle. en/ct the pin is enable/shutdown and auto restar t control functions. when system is normal operating, this pin is enable/shutdown f unction. pulling this pin below a threshold voltage of under 0.3v shuts the r egulator off, and pulling this pi n from 0.5v to 1.5v turns the regulator on. however when v out is short (v fb <0.4v), the auto restart function can be started that restart the regulator cycle by cycl e. the cycle time is set by outside capacitor (c6). please refer the below waveform and formula, the t2 cycle is regulator off time and t1 cycle is current limit time. the charge-current is 32ua and discharge-current is 1.5ua. v en/ct time t1 t2 time iin (a) 0.5v 1.5v 0 current limit .) sec ( u 5 . 1 1 6 c = 2 t .) sec ( u 32 1 6 c = 1 t under voltage lockout (uvlo) to avoid error-operation of the device at lo w input voltages an under voltage lockout is included that disables the device, if the input voltage falls below 6.0v. www.datasheet.net/ datasheet pdf - http://www..co.kr/
7/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 current limit protection the current limit is set by outside resistance (r sense ), when the sense1-sense2 voltage larger than 125mv, the current limit is happened that driver can be turned off until the drop is small than 80mv. the current limit set according to the following equation: sense xr 2 m ) 45 - 125 ( + m 125 = (a) limit current the maximum output current table is shown as below; please refer the table to design. rsense ( ? ) maximum output current (a) 50m 2.05 100m 1.03 freq =350khz freq =100khz www.datasheet.net/ datasheet pdf - http://www..co.kr/
8/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 thermal considerations the sop-8l-ep package needs a heat sink under most conditions. the heat sink connect exposed pad of AX3112/a to obtain best effect. the size of the heat sink depends on the input voltage, output voltage, out put current and ambient temperature. ? typical characteristics AX3112a www.datasheet.net/ datasheet pdf - http://www..co.kr/
9/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? typical characteristics (continuous) v cc =32v, v out =5v, i out =1.2a, c en =0.1u c out =470u v cc =32v, v out =5v, i out =1.0a, c en =0.1u, c out =40u 350khz 100khz www.datasheet.net/ datasheet pdf - http://www..co.kr/
10/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? typical characteristics (continuous) v cc =12v, v out =5v, i out =0~2a v cc =32v, v out =5v, i out =0~2a v cc =32v, v out =1.2v, i out =1.5a thermal shutdown release v cc =32v, v out =5v, i out =1.5a short circuit release www.datasheet.net/ datasheet pdf - http://www..co.kr/
11/11 axelite confidential materials, do not copy or distribute without written consent . rev.1.3 may.23, 2011 AX3112 ? package outlines detail a l h e a a2 a1 e d 7 (4x) b y c detail a y x expose pad symbol dimensions in millimeters dimensions in inches min. nom. max. min. nom. max. a - - 1.75 - - 0.069 a 1 0 - 0.15 0 - 0.06 a 2 1.25 - - 0.049 - - c 0.1 0.2 0.25 0.0075 0.008 0.01 d 4.7 4.9 5.1 0.185 0.193 0.2 e 3.7 3.9 4.1 0.146 0.154 0.161 h 5.8 6 6.2 0.228 0.236 0.244 l 0.4 - 1.27 0.015 - 0.05 b 0.31 0.41 0.51 0.012 0.016 0.02 e 1.27 bsc 0.050 bsc y - - 0.1 - - 0.004 x - 2.34 - - 0.092 - y - 2.34 - - 0.092 - 0 o - 8 o 0 o - 8 o mold flash shall not exceed 0.25mm per side jedec outline: ms-012 ba www.datasheet.net/ datasheet pdf - http://www..co.kr/

▲Up To Search▲

Price & Availability of AX3112

	To Download AX3112 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .