AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR General Description Features • • • • • • • • AP1186 is a 1.5A 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 a switcher can be achieved without the cost and complexity associated with a switching regulator. One such application is the new graphic chip sets that require anywhere from 2.4V to 2.7V supply. Adjustable or Fixed output voltage 1.5V, 1.8V, 2.5V, 3.3V, 5.0V 0.5V Maximum Dropout voltage at 1.5A Load current Built-in Thermal Shutdown Output Current Limiting Fast transient response Good noise rejection Packages: TO220-5L, TO263-5L Lead Free Finish/RoHS Compliant for Lead Free products (Note 1) Ordering Information AP 1186 Note: Package Vout K5:TO263-5L T5:TO220-5L Blank : Adj 15 : 1.5V 18 : 1.8V 25 : 2.5V 33 : 3.3V 50 : 5.0V X X Lead Free Packing L : Lead Free Package -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 Lead-free Note: X-X AP1186T5 AP1186K5 Tube Package Packaging Part Number (Note 2) Code Quantity Suffix T5 K5 TO220-5L TO263-5L 50 50 -U -U 13” Tape and Reel Part Number Quantity Suffix NA 800/Tape & Reel NA -13 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. Typical Application 3V 5V + 470uF + Vin Vctrl Vou t GND Vsense 5 4 3 2 1 470uF 2.5 /1.5A V + 470uF AP1186 Rev. 1 1 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Block Diagram Vout Vin Vsense Vctrl + + 1.25V - CURRENT LIMIT + + Adj - THERMAL SHUTDOWN Package Connect Diagram 5 PIN TO263 5 PIN TO220 FRONT VIEW FRONT VIEW 5 4 3 2 1 5 Vin Vctrl Vout Adj(GND) Vsense 4 3 2 1 Tab is Vout Vin Vctrl Vout Adj(GND) Vsense Tab is Vout Pin Descriptions Name I/O Description Vsense I 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. Adj (GND) A resistor divider from this pin to the Vout pin and ground sets the output voltage. (GND only for fixed mode) Vout O The output of the regulator. A minimum of 100uF capacitor must be connected from this pin to ground to insure stability. Vctrl I 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 by higher than the Vout pin in order for the device to regulate. A minimum of 100uF capacitor must be connected from this pin to ground to insure stability. Vin I 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. AP1186 Rev. 1 2 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Absolute Maximum Ratings Symbol Vin Vctrl PD TST TOP Parameter Input Voltage Control Input Voltage Power Dissipation Storage Temperature Operating Junction Temperature Range Rating 16 18 Internally Limited -65 to +150 Unit V V oC oC 0 to +150 Electrical Characteristics o Unless otherwise specified, these specifications apply over, Cin = 1uF, Cout = 10uF, and TJ = 0 to 150 C. Typical value refers to TA = o 25 C. Vout = Vsense. SYM. VREF Vout Parameter Reference Voltage Test Condition TA = 25oC,(VIN-VOUT) = 0.5V,IO = 10mA AP1186-Adj Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 2V≦VIN≦12V AP1186-1.5 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 2.3V≦VIN≦12V AP1186-1.8 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 3V≦VIN≦12V Output Voltage AP1186-2.5 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 3.8V≦VIN≦12V AP1186-3.3 Vctrl = VIN+1V IOUT = 10mA, TA = 25oC, 5.5V≦VIN≦12V AP1186-5.0 Vctrl = VIN+1V IO = 10mA, VOUT+0.5V<VIN<12V Line Regulation AP1186-XXX Vctrl = VIN+1V 0mA<Io<1.5A, TA=25oC AP1186-Adj (VIN – VOUT) = 2V, Vctrl = VIN + 1V VIN = 3V, 0mA<Io<1.5A, TA = 25oC AP1186-1.5 Vctrl = 4V VIN = 3.3V, 0mA<Io<1.5A, TA = 25oC AP1186-1.8 Vctrl = 4.3V Load Regulation VIN = 4V, 0mA<Io<1.5A, TA = 25oC AP1186-2.5 Vctrl = 5V VIN = 5V, 0≦IOUT≦1.5A, TA = 25oC , AP1186-3.3 TA= 25oC Vctrl = 6V VIN = 8V, 0≦IOUT≦1.5A, TA= 25oC , AP1186-5.0 TA= 25oC Vctrl = 9V Dropout Voltage Vadj = 0V for all conditions below. (Vctrl-Vout) Vin = 2.05V, Io = 1.5A Dropout Voltage Vadj = 0V for all conditions below. (Vin-Vout) Vctrl = 3V, Io = 1.5A Current Limit Vctrl = 3V, Vin = 2.05V, ∆Vo = 100mV, Vadj = 0V Minimum Load Vctrl = 5V, Vin = 3.3V, Vadj = 0V Current AP1186 Rev. 1 3 of 9 www.diodes.com Min. Typ. Max. Unit 1.225 1.250 1.275 V 1.470 1.500 1.530 1.764 1.800 1.836 2.450 2.500 2.550 V 3.235 3.300 3.365 4.900 5.000 5.100 0.2 % 1 % 12 15 mV 15 18 mV 20 25 mV 26 33 mV 40 50 mV 1.23 0.26 0.38 1.6 V V A 5 10 mA MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Electrical Characteristics ( Continued ) o Unless otherwise specified, these specifications apply over, Cin = 1uF, Cout = 10uF, and Tj = 0 to 150 C. Typical value refers o to Tj = 25 C. Vout = Vsense. SYM. Parameter Thermal Regulation Test Condition 30ms Pulse 0.01 Vctrl = 5V, Vin = 5V, Io = 1.5A, Vadj = 0V, Tj = 25, Vripple = 1Vpp at 120Hz Control Pin Vadj = 0V for all conditions below. Current Vctrl = 2.75V, Vin = 2.05V, Io = 1.5A Iadj Adjust Pin Current Vctrl = 2.75V, Vin = 2.05,Vadj = 0 Thermal TO263-5L: Control Circuitry/Power Transistor ΘJC Resistance TO220-5L: Control Circuitry/Power Transistor Junction-to-Case Ripple Rejection Note: 3. Min. Typ. Max. Unit 60 0.02 %W 70 dB 6 25 mA 50 150 µA 2.5 2.5 o C/W AP1186-ADJ incorporates an internal thermal shutdown that protects the device when the junction temperature exceeds the allowable maximum junction temperature. AP1186 Rev. 1 4 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Functional Descriptions Introduction The AP1186 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 AP1186 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 AP1186-ADJ 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 AP1186 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 AP1186-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 AP1186-ADJ Vctrl Vsense Vref Adj Iadj=50uA The AP1186-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 AP1186-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 Vin Vctrl R2+ output voltage and should be considered when very precise output voltage setting is required. Load Regulation Since the AP1186 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 AP1186 with remote sensing. Vout Vin AP1186-ADJ Vctrl R1+ Vsense Adj R1 RL R2 AP1186 Rev. 1 5 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Function Descriptions (Continued) Stability The AP1186-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 AP1186-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 AP1186-XXX incorporates an internal thermal shutdown that protects the device when the junction temperature exceeds the allowable maximum junction temperature. Although this device o 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 = 1.5A 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 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 o Note: Above table is based on the maximum junction temperature of 135 C. As shown in the above table, any of the two packages will do the job. AP1186 Rev. 1 - 0 6 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Marking Information (1) TO220-5L ( Top view ) 1186-XX: Voltage 1186-15: 1.5V 1186-18: 1.8V 1186-25: 2.5V 1186-33: 3.3V 1186-50: 5.0V 1186-XX XX XX X X Logo L: Lead Free Package Internal code Xth week: 01~52 Year: "01" = 2001 "02" = 2002 ~ (2) TO263-5L (Top view) 1186-XX: Voltage 1186-15: 1.5V 1186-18: 1.8V 1186-25: 2.5V 1186-33: 3.3V 1186-50: 5.0V Logo 1186- XX XXXX XX L: Lead Free Package Internal Code Xth Week: 01~52 Year: "01" = 2001 "02" = 2002 ~ AP1186 Rev. 1 7 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Package Information (1) Package Type: TO220-5L AP1186 Rev. 1 8 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated AP1186 1.5A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR FIXED-MODE REGULATOR Package Information (Continued) (2) Package Type: TO263-5L 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. AP1186 Rev. 1 9 of 9 www.diodes.com MARCH 2007 © Diodes Incorporated