A M I C R O S E M I LX8610-xx 1A BiCMOS Very Low Dropout Regulators C O M P A N Y P RELIMINARY D ATASHEET Dropout Voltage Typically The LX8610 family are positive very low dropout regulators. They are designed to provide a power supply for very low headroom applications, such as 3.3V– 2.5V. BiCMOS technology allows an effective series pass element resistance, RDS(ON) of 250m dropout voltage of 250mV at 1A. Low Quiescent Current and LogicControlled Shutdown help conserve battery life and increase system efficiency. Typical quiescent current is under 400µA irrespective of load current, while the shutdown current is only 10µA. The device will enter shutdown mode when the ENABLE pin is pulled low. Thermal & Short-Circuit Current Limiting: the LX8610 limits the current when the output is shorted, so protecting sensitive load circuits. The device will also turn off if the junction temperature exceeds 155°C. Available in small outline SOT-223 and 8-pin SOIC: Adjustable versions use the 8-pin SOIC and fixed output voltage devices are supplied in the 3-lead SOT-223. 250mA At 1A And 50mV At 10mA Low Quiescent Current, Under 400µA, Irrespective Of Load Shutdown Current 10µA Adjustable Output Version In 8-pin SOIC Package Fixed Outputs Of 2.5V, 3.3V Available In 3-Pin SOT-223 Package Low Reverse Leakage Current Short-Circuit And Thermal Shutdown Protection W W W . Microsemi . COM IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com 3.3V & 2.5V Supplies For Memory, Microprocessors, Clock Circuits, Etc. Portable Equipment L X 86 1 0 -xx S im p lified B lock D ia gram V OUT V IN Current Lim it Reference Current RA Charge P um p A D J* 1 .2 5 V RB E N A B LE * GND V IN /2 RA Reverse V oltage S ense Therm al S hutdown RB L X 8 6 1 0-0 0 - - L X 8 6 1 0-2 5 25K 25K L X 8 6 1 0-3 3 41K 25K LX8610-XX * A d ju sta b le 8 le a d ve rsio n on ly TJ (°C) 0 to 125°C OUTPUT ST PLASTIC SOT-233 DM Plastic SOIC 8-PIN VOLTAGE 3-PIN 3.3 2.5 ADJ (00) LX8610-33CST LX8610-25CST – LX8610-33CDM LX8610-25CDM LX8610-00CDM Note: Available in Tape & Reel. Append the letter “T” to the part number. (i.e. LX8610CDMT) Copyright 2000 Rev. 0.6f,2000-09-15 Microsemi Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 A M I C R O S E M I C O M P A N Y LX8610-xx 1A BiCMOS Very Low Dropout Regulators P RELIMINARY D ATASHEET Input Voltage (VIN) ......................................................................................................6.5V Enable Pin ..............................................................................................-0.3V to V IN+0.3V Operating Junction Temperature Plastic (ST & DM) Packages .................................125°C Storage Temperature ................................................................................... -65°C to 150°C Lead Temperature (Soldering, 10 Seconds) ...............................................................300°C Note: T A B IS G N D Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of specified terminal. ST GND/ H E A T S IN K GND/ H E A T S IN K E N A B LE PLASTIC SOT-223 PACKAGE THERMAL RESISTANCE-JUNCTION TO TAB, θJT 15°C/W* THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA DM θJLD THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA V OU T 2 GND 1 V IN 1 8 ADJ 2 7 GND/ H E A T S IN K 3 6 GND/ H E A T S IN K 4 5 V IN 150°C/W DM PACKAGE (Top View) 30°C/W PLASTIC SOIC PACKAGE THERMAL RESISTANCE-JUNCTION TO AMBIENT, 3 ST PACKAGE (Top View) V O UT W W W . Microsemi . COM 90°C/W Junction Temperature Calculation: TJ = TA + (PD x θJA). The θJA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. θJA can be improved with package soldered copper area over backside ground plane or internal power plane. θJA can vary from 45°C/W > 75°C/W depending on mounting technique. See table below for thermal resistance guidelines: Copper Area (Topside)* Copper Area (Backside)* 2.0 sq” (1290mm2) 1.0 sq” (645 mm2) 0.5 sq” (323 mm2) 0.25 sq” (161 mm2) 1.0 sq” (645 mm2) 0.5 sq” (323 mm2) 0.1 sq” (65 mm2) 0.1 sq” (65 mm2) Thermal Resistance (θJA) Board Area Possible Heat Sink Approaches using PCB Copper ST (SOT-223) 45°C/W 50°C/W 60°C/W 70°C/W DM (SOIC) 2 2.0 sq” (1290mm ) 1.0 sq” (645 mm2) 0.5 sq” (323 mm2) 0.25 sq” (161 mm2) 2 1.0 sq” (645 mm ) 0.5 sq” (323 mm2) 0.1 sq” (65 mm2) 0.1 sq” (65 mm2) 2 2.0 sq” (1290mm ) 1.0 sq” (645 mm2) 0.5 sq” (323 mm2) 0.25 sq” (161 mm2) 60°C/W 67°C/W 70°C/W 75°C/W 1 8 2 7 3 6 4 5 PACKAGE DATA 2.0 sq” (1290mm2) 1.0 sq” (645 mm2) 0.5 sq” (323 mm2) 0.25 sq” (161 mm2) *Tab of device attached to topside copper, or leads 2,3,5,6 of SOIC package Copyright 2000 Rev. 0.6f,2000-09-15 Microsemi Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 A M I C R O S E M I 1A BiCMOS Very Low Dropout Regulators P RELIMINARY D ATASHEET VIN Positive supply input for the regulator. Bypass to GND with at least 2.2µF of low ESR, ESL capacitance if supply source is further than 1 inch from the device. VOUT Output for the regulator. It is recommended to bypass to GND with at least 10µF although this is not required for regulation, rather it is needed for transient response. Size your output capacitor to meet the transient loading requirement. If you have a very dynamic load, a larger capacitor will improve the response to these load steps. GND Reference ground. The input and output bypass capacitors should be connected to this pin. In addition the tab on the SOT-223 package and pins 2,3,6, and 7 on the SOIC package are also used for heat sinking the device. ADJ Feedback pin for the regulator. For the LX8610-00, the output voltage can be set by two external resistors with the following relationship: VOUT = 1.25V * (1 + RA / RB) where RA is the resistor connected between VOUT and ADJ, and RB is the resistor connected between ADJ and GND. ENALBE Enable input. This pin has a threshold of about VIN / 2, it should be actively pulled high to enable the regulator. This can be accomplished with a resistive pull-up. When low, it turns off the regulator and puts the device in a low current shutdown state. W W W . Microsemi . COM C O M P A N Y LX8610-xx VIN 5 IN OUT LX8610-00 CIN ENABLE 4 GND 2,3 6,7 VOUT 1 RA ADJ 8 VREF COUT RB RA RB VOUT = VREF 1 + PIN DESCRIPTION Figure 1 – Typical Application Copyright 2000 Rev. 0.6f,2000-09-15 Microsemi Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 3 A M I C R O S E M I C O M P A N Y LX8610-xx 1A BiCMOS Very Low Dropout Regulators P RELIMINARY D ATASHEET Parameter Symbol Input Voltage Load Current (with adequate heatsinking) Input Capacitor (VIN to GND) Output Capacitor (VOUT to GND) VIN Min 3 10 2.2 10 LX8610 Typ Units Max 5.5 V mA µF µF 1000 10 22* * Size your output capacitor to meet the transient loading requirement. If you have a very dynamic load, a larger capacitor will improve the response to these load steps. W W W . Microsemi . COM Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C ≤ TA ≤ 125°C except where otherwise noted. Test conditions: VIN = VOUT + 1.5V; IOUT = 10mA; CIN = 10µF; COUT = 22µF; TJ = TA. Parameter Symbol Test Conditions Min LX8610-xx Typ Max Units LX8610-33 FIXED 3.3V, 1A Output Voltage VOUT Line Regulation Load Regulation VREG IREG Dropout Voltage (VDO = VIN–VOUT) VDO Short Circuit Current Quiescent Current ISC IQ Reverse Leakage Current IREV Shutdown Threshold * Shutdown Current * VSD ISD TJ = 25°C Over Temperature VIN = 3.45V to 5.5V IOUT = 10mA to 1A IOUT = 1A, VOUT OUT –1% IOUT = 0.5A, VOUT OUT – 1% IOUT = 10mA, VOUT OUT – 1% VOUT = 0V IOUT = 10mA to 1A 0V < VIN < VOUT, VOUT <3.4V (at VOUT) OV < VIN < VOUT, VOUT <3.4V (at VIN) 3.25 3.22 -50 0.8 ENABLE < 0.8V 3.3 4 5 0.25 0.15 0.05 1.25 400 400 0 VIN / 2 10 3.35 3.38 8 10 0.4 0.25 0.15 1.7 600 650 25 V mV mV V A µA µA mA V µA LX8610-25 FIXED 2.5V, 1A VOUT Line Regulation Load Regulation VREG IREG Dropout Voltage (VDO = VIN–VOUT) VDO Short Circuit Current Quiescent Current ISC IQ Reverse Leakage Current IREV Shutdown Threshold Shutdown Current VSD ISD Copyright 2000 Rev. 0.6f,2000-09-15 TJ = 25°C Over Temperature VIN = 3.1V to 5.5V, IOUT = -10mA IOUT = 10mA to 1A IOUT = 1A, VOUT OUT –1% IOUT = 0.5A, VOUT OUT – 1% IOUT = 10mA, VOUT OUT – 1% VOUT = 0V IOUT = 10mA to 1A 0V < VIN < VOUT, VOUT < 2.6V (at VOUT) 0V < VIN < VOUT, VOUT <2.6V (at VIN) 2.46 2.44 -50 0.8 ENABLE < 0.8V Microsemi Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 2.5 2.5 3 5 0.25 0.15 0.05 1.25 300 400 0 VIN / 2 10 2.54 2.56 6 10 0.4 .025 0.1 1.7 600 650 25 V mV mV V A µA µA mA V µA Page 4 ELECTRICALS Output Voltage A M I C R O S E M I LX8610-xx 1A BiCMOS Very Low Dropout Regulators C O M P A N Y P RELIMINARY D ATASHEET Parameter Symbol Test Conditions Min LX8610-xx Typ Max Units LX8610-00 ADJUSTABLE OUTPUT, 1A Reference Voltage VREF Line Regulation Load Regulation Short Circuit Current VREG IREG ISC Dropout Voltage (VDO = VIN–VOUT) VDO Quiescent Current IQ Reverse Leakage Current IREV Bias Current at ADJ Pin Shutdown Threshold Shutdown Current IBIAS VSD ISD TJ = 25°C Over Temperature VIN = VOUT + 150mV to 5.5V, IOUT = 10mA IOUT = 10mA to 1A VOUT = 0V IOUT = 1A, VIN > 4V IOUT = 0.5A, VIN > 3V IOUT = 10mA, VIN > 3V IOUT = 10mA to 1A, VIN = 5.5V 0V < VIN < VOUT, VOUT < 5.5V (at VOUT) 0V < VIN < VOUT, VOUT <5.5V (at VIN) 1.23 1.22 -50 0.8 ENABLE < 0.8V 1.22 1.25 2 7 1.25 0.25 0.15 0.05 400 400 0 100 (VIN / 2) 10 1.27 1.28 4 15 1.7 0.4 0.25 0.15 600 650 V mV mV A V W W W . Microsemi . COM µA µA mA nA V µA 25 * Note: Enable threshold and Shutdown Current apply only to 8-Pin SOIC package outline versions L X 8 6 1 0 D ro p o u t vs L o a d v s T e m p 350 300 250 0 25 75 100 125 200 150 100 ELECTRICALS 50 0 0 0 .2 5 0 .5 0 .7 5 1 FIGURE 2 – Dropout Voltage Vs. Output Current (Typical – LX8610-25CST) Copyright 2000 Rev. 0.6f,2000-09-15 Microsemi Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 A M I C R O S E M I LX8610-xx 1A BiCMOS Very Low Dropout Regulators C O M P A N Y P RELIMINARY D ATASHEET ST W W W . Microsemi . COM 3-Pin Plastic SOT-223 D Dim B1 A B B1 C D E F G H I J K L E H 2 1 3 B F G L K A J MILLIMETERS MIN MAX 1.55 1.80 0.65 0.85 2.95 3.15 0.25 0.35 6.30 6.70 3.30 3.70 2.30 BSC 4.60 BSC 6.71 7.29 – 0.91 0.02 0.10 10° MAX .084 1.04 INCHES MIN MAX 0.061 0.071 0.026 0.033 0.116 0.124 0.010 0.014 0.248 0.264 0.130 0.146 0.0905 BSC 0.181 BSC 0.264 0.287 – 0.036 .0008 .004 10° MAX 0.033 0.041 MILLIMETERS MIN MAX 4.83 5.00 3.81 3.94 1.35 1.75 0.33 0.51 – 0.77 1.27 BSC 0.19 0.25 0.13 0.25 4.80 5.21 – 8° 5.79 6.20 – 0.10 INCHES MIN MAX 0.190 0.197 0.150 0.155 0.053 0.069 0.013 0.020 – 0.030 0.050 BSC 0.007 0.010 0.005 0.010 0.189 0.205 – 8° 0.228 0.244 – 0.004 I C 8-Pin Plastic SOIC DM Dim A P B G L M C D K J F *Lead Coplanarity Note: 1. Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall not include solder coverage. Preliminary Data – Information contained in this document is pre-production data and is proprietary to LinFinity. It may not be modified in any way without the express written consent of LinFinity. Product referred to herein is offered in sample form only and LinFinity reserves the right to change or discontinue this proposed product at any time. Copyright 2000 Rev. 0.6f,2000-09-15 Microsemi Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 6 MECHANICALS A B C D F G J K L M P *LC