UNISONIC TECHNOLOGIES CO., LTD LXXLD32 CMOS IC 3A, ULTRA LOW DROPOUT (0.23V@3A) LINEAR REGULATOR DESCRIPTION The UTC LXXLD32 is a typical LDO with the features of very low dropout voltage as low as 0.23V at output current 3A. For normal operation, two supply voltages are necessary. One called control voltage from other equipment can shutdown the output voltage and it should pull and hold the voltage of EN pin less than 0.5V. Another one is the main supply voltage whose purpose is for main power conversion, to keep the power dissipation low, and to make the dropout voltage lower. Internally, in the UTC LXXLD32, there’re many functions which can be seen in the block figure to prevent the IC from being damaged. Internal Power-On-Reset (POR) circuit can control the two supply voltages to prevent fault operations of the circuit; the thermal shutdown circuit is able to protect the device from over thermal operation, and a current limit function will keep the device work safely under current over-loads. The UTC LXXLD32 can be used as an ideal to provide well supply voltage in the applications, such as front-side-bus termination on motherboard, NB applications, front side bus VTT (1.2V/3A) and note book PC applications. FEATURES * Compatible with LXXLD30 * Low Dropout VD=0.23V(typ.)@ IOUT=3A * Low ESR Output Capacitor * VREF=0.8V * Fast Transient Response * Output Voltage Adjustable through External Resistors * POR(Power-On-Reset) controlling VCNTL and VIN HSOP-8 * With internal Soft-Start * Internal Current Limit Protection * Internal Under Voltage Protection * Hysteretic Thermal Shutdown * With Power-OK Output (with a Delay Time) * Low Shutdown Quiescent Current (<30 uA) * Shutdown/Enable Control Function ORDERING INFORMATION Ordering Number LXXLD32G-SH2-R Note: XX: Output Voltage, refer to Marking Information. www.unisonic.com.tw Copyright © 2016 Unisonic Technologies Co., Ltd Package HSOP-8 Packing Tape Reel 1 of 7 QW-R502-A87.C LXXLD32 CMOS IC MARKING INFORMATION PACKAGE VOLTAGE CODE HSOP-8 AD :ADJ PIN CONFIGURATION PIN DESCRIPTION PIN NO. 1 PIN NAME GND 2 FB 3 VOUT 4 5 VIN 6 VCNTL 7 POK 8 EN MARKING DESCRIPTION Ground pin. There’s an external resistor divider connected to this pin which is necessary to give the feedback voltage to the regulator. The external circuit is combined as the follow: between VOUT and FB is R1(connected with a bypass capacitor which can improve the load transient response),and between FB and ground is R2.The value of R2 and R1 are recommended between 100Ω~10kΩ.So the output voltage is equals: R1 VOUT=0.8·(1+ )(V) R2 The output voltage pin of the regulator. There should be set an output capacitor to compensate for closed-loop and also to improve transient responses. It’s necessary to connect Pin 3 and Pin 4 together by wide tracks. This pin is the main supply input. It’s necessary to connect the Exposed Pad and VIN together for lower dropout voltage. Monitoring this pin’s voltage can reset Power-On. Power input pin of the control circuitry. Connecting this pin to a +5V (recommended) supply voltage provides the bias for the control circuitry. The voltage at this pin is monitored for Power-On Reset purpose. Output pin for Power-OK signal output. Being an open drain output, through senescing FB voltage, this pin can show the users the output voltage’s states. That’s this pin will be low under any of these two situations: the rising FB voltage is not above the VPOK threshold; the falling FB voltage is below the VPNOK threshold. That indicates the output voltage is not ready for users. Input Enable control pin. The output voltage can be shut down when this pin is below 0.3V. This pin’s voltage can be set higher than VCNTL voltage by an internal 10μA current source, and then the regulator will begin working normally. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 7 QW-R502-A87.C LXXLD32 CMOS IC BLOCK DIAGRAM VCNTL EN Power On Reset FB FB UV + Soft-Start and Control Logic VIN 0.4V - Thermal Limit EAMP + VREF 0.8V VOUT Current Limit + POK - Dealy POK 90% VREF GND UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 3 of 7 QW-R502-A87.C LXXLD32 CMOS IC ABSOLUTE MAXIMUM RATING PARAMETER SYMBOL RATINGS UNIT Supply Voltage (VCNTL to GND) VCNTL -0.3 ~ +7 V Supply Voltage (VIN to GND) VIN -0.3 ~ + 4.0 V EN and FB to GND VI/O -0.3 ~ VCNTL+0.3 V POK to GND VPOK -0.3 ~ +7 V Junction Temperature TJ 150 °С Storage Temperature TSTG -65 ~ +150 °С 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 operation is not implied. RECOMMENDED OPERATING CONDITIONS PARAMETER Supply Voltage Supply Voltage Output Voltage Control Input VCNTL=3.3±5% VCNTL=5.0±5% Output Current SYMBOL VCNTL VIN VOUT IOUT RATINGS 3~ 5.5 1.2~ 3.65 0.8 ~ 1.2 +0.8 ~ VIN-0.2 0~3 UNIT V V V V A THERMAL DATA PARAMETER SYMBOL RATINGS UNIT Junction to Ambient (Note 1) θJA 90 °C/W Note: θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. The exposed pad of HSOP-8 is soldered directly on the PCB. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 of 7 QW-R502-A87.C LXXLD32 CMOS IC ELECTRICAL CHARACTERISTICS (TA = 25°C, VCNTL = 5V, VIN = 1.5V, VOUT = 1.2V, unless otherwise specified) PARAMETER SYMBOL TEST CONDITIONS VCNTL Nominal Supply Current ICNTL EN = VCNTL VCNTL Shutdown Current ISD EN = GND VCNTL VCNTL Rising VTHR POR Threshold VIN VIN Rising VCNTL POR Hysteresis VHYS VIN Reference Voltage VREF FB =VOUT Output Voltage Accuracy IOUT=0A~3A, TJ= -25 ~125°С ∆VOUT Line Regulation IOUT=10mA,VCNTL=3~5V ∆VIN × VOUT ∆VOUT Load Regulation IOUT=0A~3A VOUT VCNTL=5V, TJ= 25°С Current Limit ILIMIT VCNTL=5V, TJ= -25 ~ +125°С VOUT=2.5V TJ= 25°С VCNTL=5V Dropout Voltage VD VOUT=1.8V TJ= 25°С IOUT=3A VOUT=1.2V TJ= 25°С Over Temperature Shutdown OTS TJ Rising Over Temperature Hysteresis OTH Under-Voltage Threshold VFB Falling EN Logic High Threshold Voltage VEN Rising EN Hysteresis EN Pin Pull-Up Current EN=GND POK Threshold Voltage for Power OK VPOK VFB Rising POK Threshold Voltage for Power Not OK VPNOK VFB Falling POK Low Voltage POK sinks 5mA UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN TYP MAX UNIT 1 1.5 mA 15 30 µA 2.5 2.7 2.9 V 0.8 0.9 1.0 V 0.4 V 0.5 V 0.8 V -1.5 +1.5 % -0.15 +0.15 %/V 0.06 0.25 4.5 4 5.7 7 0.26 0.24 0.23 150 50 0.4 0.5 0.8 100 5 90% 92% 81% 0.25 % A 0.31 0.29 0.28 V °С °С V 1.1 V mV μA 94% VREF VREF 0.4 V 5 of 7 QW-R502-A87.C LXXLD32 CMOS IC TYPICAL APPLICATION CIRCUIT 1. Using an Output Capacitor with ESR≥18mΩ 2. Using an MLCC as the Output Capacitor R3=1kΩ VCNTL +5V CCNTL=1µF 6 VCNTL POK VIN 5 VIN +1.5V CIN=22µF 7 POK UTC LXXLD32 VOUT 3 VOUT +1.2V/3A VOUT 4 R1=39kΩ EN 8 EN C1=56pF COUT=22µF FB 2 GND 1 Enable R2=78kΩ VOUT (V) 1.05 1.5 1.8 R1 (kΩ) 43 27 15 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw R2 (kΩ) 137.6 30.86 12 C1 (pF) 47 82 150 6 of 7 QW-R502-A87.C LXXLD32 CMOS IC APPLICATION INFORMATION 1. Power Sequencing When there’s no main voltage applied at VIN, it is suggested not to apply a voltage to VOUT for a long time. Because the internal parasitic diode (between VOUT to VIN) will conduct and dissipate power, there’s no protection. 2. Output Capacitor A proper output capacitor to maintain stability and improve transient response over temperature and current is necessary. Proper ESR (equivalent series resistance) and capacitance of the output capacitor should be selected properly for stability of the normal operation and good load transient response. Many kinds of capacitors can be used as an output capacitor, such as ultra-low-ESR capacitors (like ceramic chip capacitors), low-ESR bulk capacitors (like solid Tantalum, POSCap, and Aluminum electrolytic capacitors). And also the value of the output capacitors’ can be increased without limit. In the applications with large stepping load current, the low-ESR bulk capacitors are normally recommended. Decoupling ceramic capacitors are recommended to be placed at the load and ground pins very closely and also the impedance of the layout must be minimized. 3. Input Capacitor In order to prevent the input rail from dropping, the proper input capacitor to supply current surge during stepping load transients is required. Because the limited slew rate of the surge currents, more parasitic inductance needs more input capacitance. Ultra-low-ESR capacitors (>100mF, ESR<300mW) is recommended for the input capacitor. 4. Feedback Network The following figure shows the feedback network between VOUT GND and FB pins. Working with the internal error amplifier, the feedback network can provide proper frequency response for the UTC LXXLD32. VOUT VOUT R1 VERR EAMP FB VFB VREF R2 C1 ESR COUT 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 www.unisonic.com.tw 7 of 7 QW-R502-A87.C