LX8580 7A V ERY LOW D ROPOUT P OSITIVE A DJUSTABLE R EGULATOR T H E I N F I N I T E P O W E R O F I P N N O VA T I O N R O D U C T I O N DESCRIPTION The LX8580 is a high-performance, very low dropout voltage regulator, designed for use with advanced microprocessors. This product can be used with separate voltage supplies for the control and power sections, allowing a power section dropout voltage as low as 100mV. The LX8580 can also be used in a single voltage supply configuration, with a dropout performance similar to that of the LX8584 (1.3V at 7A). The LX8580 is supplied in a fiveterminal TO-220 package, which allows the D A T A S H E E T K E Y F E AT U R E S implementation of remote (Kelvin) voltage sensing. This sensing compensates for output voltage variations due to load changes and resistive voltage drops in connectors and board traces. Typical load regulation measured at the sense pin is less than 1mV for a load current step of 7mA to 7A. The LX8580 is ideal for generating a secondary 2 - 2.5V low voltage supply on a motherboard where a 3.3V supply is already available. NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com. Low Dropout, 800mV Max. at 7A Output Current in Dual Supply Mode Fast Transient Response Remote Sensing ! 1mV Load Regulation ! Adjustable Output ! No Supply Sequencing Problems in Dual Supply Mode A P P L I C AT I O N S Microprocessor Supplies 3.3V to 2.5V Processor Power Supplies High-Current Regulators Post Regulators for Switching Supplies PRODUCT HIGHLIGHT S P E C I A L C A PA B I L I T I E S O F T H E LX8580 T O A L L O W 44% S M A L L E R LDO T H E R M A L D I S S I PAT I O N 4 VCTRL VCTRL VOUT + 1.3V Max OUTPUT 3 VOUT LX8580 5 VPWR VPWR VOUT + VDROPOUT SENSE 1 ADJUST 2 RA LOAD R VOUT = VREF 1 + B + IADJ x RB R A RB PA C K A G E O R D E R I N F O R M AT I O N Copyright (c) 1999 Rev. 1.0 11/99 TA (C) Dropout Voltage 0 to 125 0.1V - 0.8V LINFINITY TO-220 P Plastic 5-pin TO-263 DD Plastic 5-pin LX8580-00CP LX8580-00CDD MICROELECTRONICS INC. 11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570 1 PRODUCT DATABOOK 1996/1997 LX8580 7A V ERY L OW D ROPOUT POSITIVE A DJUSTABLE R EGULATOR P R O D U C T I O N A B S O L U T E M A X I M U M R AT I N G S D A T A S H E E T PACKAGE PIN OUTS (Note 1) Power Dissipation ...................................................................................... Internally Limited VPWR Input Voltage ........................................................................................................... 7V VCTRL Input Voltage ......................................................................................................... 13V Operating Junction Temperature Plastic (P Package) ................................................................................................ 150C Storage Temperature Range ...................................................................... -65C to 150C Lead Temperature (Soldering, 10 seconds) ............................................................. 300C TAB IS OUTPUT V PWR VCTRL OUTPUT ADJUST SENSE 5 1 Note 1. Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal. P PACKAGE (Top View) T H E R M A L D ATA TAB IS OUTPUT P PACKAGE: THERMAL RESISTANCE-JUNCTION TO TAB, JT 3.0C/W THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA 60C/W DD PACKAGE: THERMAL RESISTANCE-JUNCTION TO TAB, JT 3.0C/W THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA 60C/W 5 V PWR 4 VCTRL 3 OUTPUT 2 ADJUST 1 SENSE DD PACKAGE (Top View) Junction Temperature Calculation: TJ = TA + (PD x JA). The JA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. BLOCK DIAGRAM VCTRL Control Power Current Limiting Amplifier VPWR OUTPUT Thermal Overload Voltage Regulation Amplifier 2 SENSE VREF ADJUST Copyright (c) 1999 Rev. 1.0 11/99 PRODUCT DATABOOK 1996/1997 LX8580 7A V ERY LOW D ROPOUT POSITIVE A DJUSTABLE R EGULATOR P R O D U C T I O N D A T A S H E E T ELECTRICAL CHARACTERISTICS (Unless otherwise specified, these specifications apply over the operating ambient temperatures 0C TA 125C. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.) Parameter Reference Voltage Line Regulation Load Regulation Thermal Regulation Thermal Resistance Ripple Rejection Control Pin Current (Note 3) Adjust Pin Current Current Limit Dropout Voltage (Control Section) Minimum VCTRL (Note 2) (VPWR - VOUT) Dropout Voltage (Power Section) Minimum VPWR (Note 2) (VPWR - VOUT) (VADJ = 0) Minimum Load Current Symbol VREF Test Conditions VCTRL = 2.75V, VPWR = 2V, ILOAD = 10mA, TJ = 25C VCTRL = 2.7V to 6V, VPWR = 1.75V to 5.5V, IOUT = 10mA to 4A VCTRL = 2.7V to 6V, VPWR = 2.05V to 5.5V, IOUT = 10mA to 7A VREF (VIN) VCTRL = 2.5V to 12V, VPWR = 1.75V to 5.5V, ILOAD = 10mA, TJ = 25C VCTRL = 2.5V to 12V, VPWR = 1.75V to 5.5V, ILOAD = 10mA VREF (IOUT) VCTRL = 2.75V, VPWR = 2.1V, ILOAD = 10mA to 7A (VADJ = 0) VOUT (Pwr) 30ms Pulse RJT Control Circuitry/Power Transistor VCTRL = VPWR = 3.75V Avg, VRIPPLE = 1VP-P, VADJ = 0V, IOUT = 4A ICTRL VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 100mA VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 4A VCTRL = 2.75V, VPWR = 1.75V, ILOAD = 4A VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 7A IADJ VCTRL = 2.75V, VPWR = 2.05V, ILOAD = 0mA (VADJ = 0) VCTRL = 2.75V, VPWR = 2.05V, VOUT = 100mV (VADJ = 0) I(MAX) VCTRL - VOUT VPWR = 2.05V, ILOAD = 100mA VPWR = 2.05V, ILOAD = 1A VPWR = 2.05V, ILOAD = 2.75A VPWR = 2.05V, ILOAD = 4A VPWR = 2.05V, ILOAD = 7A VPWR - VOUT VCTRL = 2.75V, ILOAD = 100mA VCTRL = 2.75V, ILOAD = 1A VCTRL = 2.75V, ILOAD = 2.75A VCTRL = 2.75V, ILOAD = 4A, TJ = 25C VCTRL = 2.75V, ILOAD = 4A VCTRL = 2.75V, ILOAD = 7A, TJ = 25C VCTRL = 2.75V, ILOAD = 7A VCTRL = 5V, VPWR = 3.3V, VADJ = 0V Min. 1.243 1.237 1.237 60 7.1 LX8580 Typ. Max. 1.250 1.250 1.250 1 2 2 0.002 0.65 80 3 30 33 60 60 9 0.90 1.00 1.05 1.06 1.10 0.05 0.10 0.20 0.30 0.30 0.52 0.56 5 1.257 1.263 1.263 3 6 7 0.020 2.70 10 60 70 120 120 1.15 1.15 1.18 1.20 1.30 0.17 0.22 0.38 0.40 0.50 0.62 0.80 10 Units V V V mV mV mV %/W C/W dB mA mA mA mA A A V V V V V V V V V V V V mA Note 2. Dropout is caused by either minimum control voltage (VCTRL) or minimum power voltage (VPWR). Both parameters are specified with respect to the output voltage. The specifications represent the minimum input/output voltage required to maintain 1% regulation. Note 3. The control pin current is the drive current required for the output transistor. This current will track output current with roughly a 1:100 ratio. The minimum value is equal to the quiescent current of the device. Copyright (c) 1999 Rev. 1.0 11/99 3 PRODUCT DATABOOK 1996/1997 LX8580 7A V ERY L OW D ROPOUT POSITIVE A DJUSTABLE R EGULATOR P D R O D U C T I O N A T A S H E E T FUNCTIONAL PIN DESCRIPTION Pin # Description SENSE 1 This pin is the positive side of the reference voltage for the device. With this pin it is possible to Kelvin-sense the output voltage at load. ADJUST 2 This pin is the negative side of the reference voltage for the device. Ripple rejection can be improved by adding a small bypass capacitor from the Adjust pin to ground. The capacitor value should be selected so that CR 1 / 2FRRA , where FR is the ripple frequency and RA is the value of the resistor between the output and sense leads of the LX8580. OUTPUT 3 This is the power output of the device. VCTRL 4 This pin is the voltage supply pin for the control circuitry of the device. The current flow into this pin will be about 1% of the output current. For the device to regulate, the voltage at this pin must be between 1.0V and 1.3V greater than the output voltage. VPWR 5 This is the collector of the power section of the LX8580. The output load current is supplied through this pin. For the device to regulate, the voltage at this pin must be between 0.1V and 0.8V greater than the output voltage (higher output currents require higher voltages between VPWR and OUTPUT). B A S I C A P P L I C AT I O N C I R C U I T Tantalum 33F 10V 4 x 19 2W 5% (Parallel Connected) VCTRL 5.0V 0.259 VPWR "Electronic Heatsink" Resistor reduces thermal load on LDO heatsink to 6.9W OUTPUT LX8580 2.89 (MAX) VOUT = 2.775 2.67 (MIN) SENSE ADJUST 1219 1% 6000F LOAD Tantalum 100F 10V *Note 1479 1% 5A (4X Sanyo 6mV 1500GK 6.3V 1500F) SYSTEM GROUND *Note: For improved transient response, add capacitor as shown (typical 15F). PRODUCTION DATA - Information contained in this document is proprietary to LinFinity, and is current as of publication date. This document may not be modified in any way without the express written consent of LinFinity. Product processing does not necessarily include testing of all parameters. Linfinity reserves the right to change the configuration and performance of the product and to discontinue product at any time. 4 Copyright (c) 1999 Rev. 1.0 11/99