AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR General Description Features • • • • • • • • 0.85V maximum dropout voltage at 4A load current Built-in Thermal shutdown Output current limiting Adjustable or fixed output voltage 1.5V, 1.8V, 2.5V, 3.3V, 5.0V Fast transient response Good noise rejection Packages: TO220-5L and TO263-5L Lead Free Finish/RoHS Compliant for Lead Free products (Note 1) AP1184 is a 4A regulator with extremely low dropout voltage. This product is specifically designed to provide well regulated supply for applications requiring 2.8V or lower voltages from 3.3V ATX power supplies where high efficiency of the switch can be achieved without the cost and complexity associated with switching regulator. One such application is the new graphic chipsets that requires anywhere from 2.4V to 2.7V supply. Ordering Information AP1184 XX - XX X X Note: Package Vout Lead Free Packing K5 : TO263-5L T5 : TO220-5L Blank : Adj 15 = 1.5V 18 = 1.8V 25 = 2.5V 33 = 3.3V 50 = 5.0V L : Lead Free -U : Tube -13 : Taping 1. RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7. Device Lead-free AP1184K5 AP1184T5 Tube/Bulk Package Packaging Part Number Code (Note 2) Quantity Suffix K5 T5 TO263-5L TO220-5L 50 50 -U -U 13” Tape and Reel Part Number Quantity Suffix 800/Tape & Reel NA Lead-free Note: 2. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at http://www.diodes.com/datasheets/ap02001.pdf. AP1184 Rev. 2 1 of 11 www.diodes.com MAY 2007 © Diodes Incorporated -13 NA AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Pin Assignments FRONT VIEW FRONT VIEW 5 4 3 2 1 Vin Vctrl Vout Adj(GND) Vsense 5 4 3 2 1 Vin Vctrl Vout Adj(GND) Vsense Tab is Vout Tab is Vout TO220-5L TO263-L Pin Descriptions Pin Numbers with standard type are for TO220-5L, TO263-5L packages. Name Adj (GND) I/O Vsense I Vin I Vctrl I NC Vout AP1184 Rev. 2 O Description A resistor divider from this pin to the Vout pin and ground sets the output voltage. (GND only for fixed mode) This pin is the positive side of the reference that allows remote load sensing to achieve excellent load regulation. A minimum of 10uF capacitor must be connected from this pin to ground to insure stability. The input of the regulator. Typically a large storage capacitor is connected from this pin to ground to insure that the input voltage does not sag below the minimum dropout voltage during the load transient response. This pin must always be higher than Vout in order for the device to regulate. This pin is the supply pin for the internal control circuit as well as the base drive for the pass transistor. This pin must always be higher than the Vout pin in order to regulate the device. A minimum of 100uF capacitor must be connected from this pin to ground to insure stability. No connection The output of the regulator. A minimum of 100uF capacitor must be connected from this pin to ground to insure stability. 2 of 11 www.diodes.com MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Block Diagram Vout Vin Vsense Vctrl + + 1.25V - CURRENT LIMIT + + - THERMAL SHUTDOWN Adj Typical Application Circuit 3.3V + 470uF Vin Vctrl 5V 2.5V /4A Vout GND + Vsense + AP1184-2.5V 470uF 470uF Absolute Maximum Ratings Symbol VIN Vctrl PD TST TOP AP1184 Rev. 2 Parameter Input Voltage Control Input voltage Power dissipation Storage temperature Range Operation Junction Temperature Range 3 of 11 www.diodes.com Rating 16 18 Internally limited -65 to +150 0 to +125 Unit V V o C C o MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Electrical Characteristics ( Under Operating Conditions ) o o Unless otherwise specified, these specifications apply over, Cin = 1uF, Cout = 10uF, and Tj = 0 to 150 C. Typical value refer to TA = 25 C. Vout = Vsense. Sym. Parameter VREF Reference Voltage Line Regulation Vout Output Voltage Load Regulation Dropout Voltage (Vctrl –Vout) Dropout Voltage (Vin – Vout) Test Condition o IO =10mA, TA = 25 C, (Vin-Vout) = 0.7V, AP1184-Adj Vctrl = VIN+1V o IO = 10mA, VOUT+0.7V<VIN<12V, TA = 25 C AP1184-XXX Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 2.2VφVINφ12V AP1184-1.5 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 2.5VφVINφ12V AP1184-1.8 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 3.2VφVINφ12V AP1184-2.5 Vctrl = VIN+1V o IOUT = 10mA, TA = 25 C, 4.0VφVINφ12V AP1184-3.3 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 5.7VφVINφ12V AP1184-5.0 Vctrl = VIN+1V o 0mA<Io<4A, TA= 25 C AP1184-Adj (VIN - VOUT) =2V ,Vctrl = VIN + 1V o VIN = 3V, 0mA<Io<4A, TA = 25 C AP1184-1.5 Vctrl = 4V o VIN = 3.3V, 0mA<Io<4A, TA = 25 C AP1184-1.8 Vctrl = 4.3V o VIN = 4V, 0mA<Io<4A, TA = 25 C AP1184-2.5 Vctrl = 5V o VIN = 5V, 0mA<Io<4A, TA = 25 C AP1184-3.3 Vctrl = 6V o VIN = 8V, 0mA<Io<4A, TA = 25 C AP1184-5.0 Vctrl = 9V Vadj = 0V for all conditions below. Vin = 2.05V, Io = 1.5A Vin = 2.05V, Io = 3A Vin = 2.05V, Io = 4A Vadj = 0V for all conditions below. Vctrl = 2.75V, Io = 1.5A Vctrl = 2.75V, Io = 3A Vctrl =2.75V, Io =4A Vctrl = 2.75V, Vin = 2.05V, ΔVo = 100mV, Vadj = 0V Current Limit Minimum Load Vctrl = 5V, Vin = 3.3V, Vadj = 0V Current Thermal Regulation 30mS Pulse Vctrl = 5V, Vin = 5V, Io = 4A, Vadj = 0V, Tj = 25, Vripple =1Vpp Ripple Rejection at 120Hz Vadj = 0V for all conditions below. Vctrl = 2.75V, Vin = 2.05V, Io = 1.5A Control Pin Current Vctrl = 2.75V, Vin = 2.05V, Io = 3A Vctrl = 2.75V, Vin = 2.05V, Io = 4A AP1184 Rev. 2 4 of 11 www.diodes.com Min. Typ. Max. Unit 1.225 1.250 1.275 V 0.2 % 1.470 1.500 1.530 V 1.764 1.800 1.836 V 2.450 2.500 2.550 V 3.235 3.300 3.365 V 4.900 5.000 5.100 V 1 % 12 15 mV 15 18 mV 20 25 mV 26 33 mV 40 50 mV 1.10 1.15 1.18 1.25 0.26 0.50 0.70 0.38 0.60 0.85 4.2 60 V V A 5 10 mA 0.01 0.02 %/W 70 6 30 33 dB 25 60 70 mA MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Electrical Characteristics ( Continued ) o o Unless otherwise specified, these specifications apply over, Cin = 1uF, Cout = 10uF, and Tj = 0 to 150 C. Typical value refer to TA = 25 C. Vout = Vsense. Sym. I adj Parameter Adjust Pin Current θJA Thermal Resistance Junction-to-Ambient θJC Thermal Resistance Junction-to-Case Note: 3. 4. 5. Test Condition Min. Typ. Max. Unit Vctrl = 2.75V, Vin = 2.05,Vadj = 0 50 150 µA TO263-5L: Control Circuitry/Power Transistor (Note 4) TO220-5L: Control Circuitry/Power Transistor (Note 5) 61 31 O TO263-5L: Control Circuitry/Power Transistor (Note 4) TO220-5L: Control Circuitry/Power Transistor (Note 5) 7 5 O O O C/W C/W C/W C/W AP1184-ADJ incorporates an internal thermal shutdown that protects the device when the junction temperature exceeds the allowable maximum junction temperature. Test conditions for TO263-5L: Device mounted on 2oz copper, minimum recommended pad layout, FR-4 PCB. Test conditions for TO220-5L: with copper area of approximately 3in2, 1oz. Package TO263-5L/TO220-5L Max Pd. 2.4W~4.4W Remarks With heat sink or amount of copper board needed. Functional Descriptions Introduction The AP1184 regulator is a 5 terminal device designed specifically to provide extremely low dropout voltages comparable to the PNP type without the disadvantage of the extra power dissipation due to the base current associated with PNP regulators. This is done by bringing out the control pin of the regulator that provides the base current to the power NPN and connecting it to a voltage that is greater than the voltage present at the Vin pin. This flexibility makes the AP1184 ideal for applications where dual inputs are available such as a computer motherboard with an ATX style power supply that provides 5V and 3.3V to the board. One such application is the new graphic chip sets that require anywhere from 2.4V to 2.7V supply. The AP1184 can easily be programmed with the addition of two external resistors to any voltages within the range of 1.25V to 15.5V. Another major requirement of these graphic chips is the need to switch the load current from zero to several amps in tens of nanoseconds at the processor pins, which translates to an approximately 300 to 500ns of current step at the regulator. In addition, the output voltage tolerances are also extremely tight and they include the transient response as part of the specification. The AP1184 is specifically designed to meet the fast current transient needs as well as providing an accurate initial voltage, reducing the overall system cost with the need for fewer number of output capacitors. Another feature of the device is its true remote sensing capability that allows accurate voltage setting at the load rather than at the device. Output Voltage Setting The AP1184-ADJ can be programmed to any voltages in the range of 1.25V to 15.5V with the addition of R1 and R2 external resistors according to the following formula: Vout = Vref (1+R2/R1) + Iadj * R2 where : Vref = 1.25V & Iadj=50uA Typically Vin Vout AP1184-ADJ Vctrl Vsense Adj Iadj=50uA AP1184 Rev. 2 5 of 11 www.diodes.com Vref R1+ R2+ MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Functional Descriptions ( Continued ) The AP1184-ADJ keeps a constant 1.25V between the Vsense pin and the Adj pin. By placing a resistor R1 across these two pins and connecting the Vsense and Vout pin together, a constant current flows through R1, adding to the Iadj current and into the R2 resistor producing a voltage equal to the (1.25/R1)*R2 + Iadj*R2. This voltage is then added to the 1.25V to set the output voltage. This is summarized in the above equation. Since the minimum load current requirement of the AP1184-ADJ is 10mA, R1 is typically selected to be a 121Ω resistor so that it automatically satisfies this condition. Notice that since the Iadj is typically in the range of 50uA it only adds a small error to the output voltage and should be considered when very precise output voltage setting is required. Load Regulation Since the AP1184 has separate pins for the output (Vout) and the sense (Vsense), it is ideal for providing true remote sensing of the output voltage at the load. This means that the voltage drops due to parasitic resistance such as PCB traces between the regulator and the load are compensated for using remote sensing. Figure following shows a typical application of the AP1184-ADJ with remote sensing. Vin Vin Vout AP1184-ADJ Vsense Vctrl Vctrl Adj R1 RL R2 Stability The AP1184-XXX requires the use of an output capacitor as part of the frequency compensation in order to make the regulator stable. Typical designs for the microprocessor applications use standard electrolytic capacitors with typical ESR in the range of 50 to 100mΩ and an output capacitance of 100uF to 1000uF. Fortunately as the capacitance increases, the ESR decreases resulting in a fixed RC time constant. The AP1184-XXX takes advantage of the phenomena in making the overall regulator loop stable. For most applications a minimum of 100uF aluminum electrolytic capacitor insures both stability and good transient response. Thermal Design The AP1184-XXX incorporates an internal thermal shutdown that protects the device when the junction temperature exceeds the o allowable maximum junction temperature. Although this device can operate with junction temperatures in the range of 150 C, it is recommended that the selected heat sink be chosen such that during maximum continuous load operation, the junction temperature is kept below this number. The example below shows the steps in selecting the proper surface mount package. Assuming, the following conditions: Vout = 2.5V Vin = 3.3V Vctrl = 5V Iout = 2A DC Avg. Calculate the maximum power dissipation using the following equation: Pd = Iout * ( Vin - Vout) + ( Iout /60) * ( Vctrl - Vout ) Pd = 2 * (3.3-2.5) + (2/60) * (5-2.5) = 1.68W Using table below select the proper package and the amount of copper board needed. Package TO263-5L Note: 6. Copper Area Pad Size-1.4”X1.4” θJA (oC/W) 25-45 Max Pd (TA = 25oC) 2.4W-4.4W Max Pd (TA = 45oC) 2.0W-3.6W Above table is based on the maximum junction temperature of 135oC. As shown in the above table, any of the two packages will do the job. AP1184 Rev. 2 6 of 11 www.diodes.com MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Performance Characteristics 800 750 700 1200 Vpower = 2.05 V Vpower Dropout Voltage (mV) Vcontrol Dropout Voltage (mV) 1100 1000 Tj = 20 oC 900 Tj = 120 oC 800 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Vcontrol = 2.75 V 650 600 550 500 Tj = 120 oC 450 400 350 300 Tj = 20 oC 250 200 150 100 50 0 Output Current (A) 0.5 0 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Output Current (A) Vcontrol Dropout Voltage vs Output Current Vpower Dropout Voltage vs Output Current 1. 253 0. 15 0. 14 1. 252 0. 12 1. 251 Load Regulation (%) Reference Voltage (V) 0. 10 1. 250 1. 249 1. 248 1. 247 0 Tj = 120 oC 0. 08 0. 06 0. 04 Tj = 20 oC 0. 02 20 40 60 80 Junction Temperature ( oC) 100 120 0 Reference Voltage vs Junction Temperature AP1184 Rev. 2 7 of 11 www.diodes.com 0 0.5 1.0 1.5 2.0 2.5 Output Current (A) 3.0 3.5 4.0 Load Regulation vs Output Current MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Performance Characteristic ( Continued ) VCONTROL = 5.0V VPOWER = 3.3V VOUT = 2.5V CCONTROL=10uF CPOWER = 100uF CADJ = 0.1uF COUT = 470uF ILOAD 10mA to 4A Transient Response AP1184 Rev. 2 8 of 11 www.diodes.com MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Marking Information (1) TO263-5L (Top view) 1184-XX: Voltage 1184-15: 1.5V 1184-18: 1.8V 1184-25: 2.5V 1184-33: 3.3V 1184-50: 5.0V Logo 1184- XX YY WW X X L : Lead Free Internal Code Xth Week: 01~52 Year: "01" = 2001 "02" = 2002 ~ (2) TO220-5L ( Top view ) 1184-XX: Voltage 1184-15: 1.5V 1184-18: 1.8V 1184-25: 2.5V 1184-33: 3.3V 1184-50: 5.0V 1184-XX YY WW X X Logo L : Lead Free Internal code Xth week: 01~52 Year: "01" = 2001 "02" = 2002 ~ AP1184 Rev. 2 9 of 11 www.diodes.com MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Package Information ( unit: mm ) (1) TO263-5L (2) TO220-5L AP1184 Rev. 2 10 of 11 www.diodes.com MAY 2007 © Diodes Incorporated AP1184 4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR IMPORTANT NOTICE Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to any product herein. Diodes Incorporated does not assume any liability arising out of the application or use of any product described herein; neither does it convey any license under its patent rights, nor the rights of others. The user of products in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on our website, harmless against all damages. LIFE SUPPORT Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written approval of the President of Diodes Incorporated. AP1184 Rev. 2 11 of 11 www.diodes.com MAY 2007 © Diodes Incorporated