AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Features General Description 1.4V maximum dropout at full load current Built-in thermal shutdown • Output current limiting • Adjustable output voltage or fixed 1.5V, 1.8V, 2.5V, 3.3V, 5.0V • Fast transient response • Good noise rejection • Package : TO252, TO263, TO220 AP1084 is a low dropout positive adjustable or fixedmode regulator with minimum of 5.0A output current capability. The product is specifically designed to provide well-regulated supply for low voltage IC applications such as high-speed bus termination and low current 3.3V logic supply. AP1084 is also well suited for other applications such as VGA cards. AP1084 is guaranteed to have lower than 1.4V dropout at full load current making it ideal to provide well-regulated outputs of 1.25 to 3.3V with 4.7 to 12V input supply. • • Ordering Information AP1084 X Low Dropout Regulator X X X Package Vout D : TO252-3L K : TO263-3L T : TO220-3L Blank : Adj 15 = 1.5V 18 = 1.8V 25 = 2.5V 33 = 3.3V 50 = 5.0V Lead Free Packing Blank : Normal Blank : Tube L : Lead Free Package A : Taping Typical Circuit 5.0V to 3.3V Fixed Mode Regulator Adjustable Regulator 5V 5V C1 100uF C1 100uF Vin Vin Vout GND Vout 3.3V/5A C2 100uF Adj 2.5V/5A R1 121Ω R2 121Ω C2 100uF Tab is Vout Tab is Vout Note: Vo = VREF ∗ (1+ R2 ) R1 This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product. Rev.1.0 Aug.27, 2004 1/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Block Diagram Vin 3 2 Vout + + － 1.25V + CURRENT LIMIT + － Thermal Shutdown 1 Adj Connection Diagram TO263 TO252 FRONT VIEW FRONT VIEW Vout 2 1 2 Adj (GND) Tab is Vout FRONT VIEW Vin 3 Vin 3 TO220 Vout 1 3 Vin 2 Vout 1 Adj (GND) Adj (GND) Tab is Vout Tab is Vout Pin Descriptions NAME I/O Adj (GND) Vout Vin O I PIN # FUNCTION 1 Adjustable (Ground only for fixed mode) 2 The output of the regulator. A minimum of 10uF capacitor must be connected from this pin to ground to insure stability. 3 The input pin of 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 1.4V higher than Vout in order for the device to regulate properly. Anachip Corp. www.anachip.com.tw Rev.1.0 Aug.27, 2004 2/8 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Absolute Maximum Ratings Symbol Parameter Rating Vin PD TST DC Supply Voltage Power Dissipation Storage Temperature TOP Operating Junction Temperature Range Electrical Characteristics SYM. VREF PARAMETER Reference Voltage AP1084-XXX AP1084-1.5 AP1084-1.8 Line Regulation AP1084-2.5 AP1084-3.3 AP1084-5.0 AP1084-Adj AP1084-1.5 Load Regulation AP1084-1.8 AP1084-2.5 ∆Vo θ JA θ JC AP1084-3.3 AP1084-5.0 Dropout Voltage Current Limit Minimum Load Current Temperature Stability Thermal Resistance Junction-to-Ambient (No heat sink ;No air flow) Thermal Resistance Junction-to-Case Unit -0.3 to 12 V Internally Limited oC -65 to +150 o 0 to +150 C (Under Operating Conditions) CONDITIONS (Notes) Io=10mA, Tj=25oC, (Vin-Vout)=1.5V o IO=10mA, VOUT+1.5V<VIN<12V, TJ =25 C o IOUT = 10mA, TJ = 25 C, 3V≦VIN≦12V IOUT = 10mA, TJ = 25oC, 3.3V≦VIN≦12V o IOUT = 10mA, TJ = 25 C, 4V≦VIN≦12V o IOUT = 10mA, TJ = 25 C, 4.8V≦VIN≦12V IOUT = 10mA, TJ = 25oC, 6.5V≦VIN≦12V VIN=3.3V, 0mA<Io<5A, TJ =25oC (Note 1,2) o VIN=3V, 0mA<Io<5A, TJ =25 C (Note 1,2) VIN=3.3V, 0mA<Io<5A o TJ =25 C (Note 1,2) VIN=4V, 0mA<Io<5A o TJ =25 C (Note 1,2) o VIN = 5V, 0mA<Io<5A , TJ=25 C (Note 1,2) o VIN = 8V, 0mA<Io<5A, TJ=25 C (Note 1,2) Io=5.0A (∆Vout = 1% Vout) Vin-Vout=5V MIN 1.225 TYP 1.250 MAX 1.275 0.2 1.530 1.836 2.550 3.365 5.100 UNIT V % V V V V V 1.470 1.764 2.450 3.235 4.900 1.500 1.800 2.500 3.300 5.000 1 % 12 15 mV 15 18 mV 20 25 mV 26 40 1.3 33 50 1.4 mV mV V A 5 10 mA 5.1 Io=10mA 0.5 TO-252 TO-263 TO-220 98 91 83 TO-252: Control Circuitry/Power Transistor TO-263: Control Circuitry/Power Transistor TO-220: Control Circuitry/Power Transistor 15 10 0.65/2.7 % O C/W O C/W Note 1: See thermal regulation specifications for changes in output voltage due to heating effects. Line and load regulation are measured at a constant junction temperature by low duty cycle pulse testing. Load regulation is measured at the output lead = 1/18” from the package. Note 2:Line and load regulation are guaranteed up to the maximum power dissipation of 15W. Power dissipation is determined by the difference between input and output and the output current. Guaranteed maximum power dissipation will not be available over the full input/output range. Anachip Corp. www.anachip.com.tw Rev.1.0 Aug.27, 2004 3/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Functional Description Introduction The AP1084 adjustable Low Dropout (LDO) regulator is a 3 terminal device that can easily be programmed with the addition of two external resistors to any voltages within the range of 1.25 to 5V. The AP1084 only needs 1.4V differential between Vin and Vout to maintain output regulation. In addition, the output voltage tolerances are also extremely tight and they include the transient response as part of the specification. For example, Intel VRE specification calls for a total of +/- 100mV including initial tolerance, load regulation and 0 to 5.0A load step. The AP1084 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 output capacitors. Output Voltage Setting The AP1084 can be programmed to any voltages in the range of 1.25V to 5V with the addition of R1 and R2 external resistors according to the following formula: Vout = Vref (1+ R2/R1) +Iadj *R2 , where Vref = 1.25 typically, Iadj = 55uA typically R1&R2 as shown at below Vin Vout AP1084 Adj Vref R1 Iadj=55uA R2 output voltage at the load. The best load regulation is achieved when the bottom side of R2 is connected to the load and the top-side of R1 resistor is connected directly to the case or the Vout pin of the regulator and not to the load. It is important to note that for high current applications, this can re-present a significant percentage of the overall load regulation and one must keep the path from the regulator to the load as short as possible to minimize this effect. The AP1084 keeps a constant 1.25V between the output pin and the adjust pin. By placing a resistor R1 across these two pins 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 which will be 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 AP1084 is 10mA, R1 is typically selected to be 121Ω resistor so that it automatically satisfies the minimum current requirement. Notice that since Iadj is typically in the range of 55uA it only adds a small error to the output voltage and should only be considered when a very precise output voltage setting is required. For example, in a typical 3.3V application where R1=121Ω and R2=200Ω the error due to Iadj is only 0.3% of the nominal set point. Stability The AP1084 requires the use of an output capacitor as part of the frequency compensation in order to make the regulator stable. For most applications a minimum of 10uF aluminum electrolytic capacitor insures both stability and good transient response. Load Regulation Since the AP1084 is only a 3 terminal device, it is not possible to provide true remote sensing of the Anachip Corp. www.anachip.com.tw Rev.1.0 Aug.27, 2004 4/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Functional Description (Continued) Thermal Design The AP1084 incorporates an internal thermal shutdown that protects the device when the junction temperature exceeds the maximum allowable junction temperature. Although this device can operate with junction temperatures in the range of 150oC, it is recommended that the selected heat sink be chosen such that during maximum continuous load operation the junction temperature is kept below the temperature. Layout Consideration The output capacitors must be located as close to the Vout terminal of the device as possible. It is recommended to use a section of a layer of the PC board as a plane to connect the Vout pin to the output capacitors to prevent any high frequency oscillation that may result due to excessive trace inductance. Anachip Corp. www.anachip.com.tw Rev.1.0 Aug.27, 2004 5/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Performance Characteristics 0.20 2. 0 Output Voltage Deviation (%) 1. 8 1. 6 Dropout Voltage (V) 1. 4 1. 2 0 I load=1.5A -0.20 Tj = 25 oC 1. 0 -0.40 0. 8 Tj = 125 oC 0. 6 -0.80 0. 4 0. 2 0 0 1 2 3 -1 5 4 Output Current (A) -25 Dropout Voltage vs Output Current 0 25 50 Temperature ( oC) 75 100 125 Load Regulation vs Temperature 2 1 0.8 1 0. 5 0 -0.5 -1 -1.5 -2 -50 -25 0 25 50 Temperature ( oC) 75 100 125 150 Output Voltage Deviation (%) Output Voltage Change (%) 1.5 0.6 0.4 0.2 0 2 4 7.5 Cin=1uF Cout=10uF Tantalum 6.5 5.5 40 20 0 -20 -40 0 20 40 60 80 100 120 140 160 180 200 TIME (us) Load Current (A) Output Voltage Deviation (mV) Output Voltage Deviation (mV) Input Voltage (V) Percent Change in Output Voltage vs Temperature Line Transient Response 6 8 10 Input Voltage (V) 12 Line Regulation 60 Cin=1uF Cout=10uF Tantalum Preload=100mA 40 20 0 -20 -40 6 4 2 0 0 10 20 30 40 50 TIME (us) 60 70 80 90 100 Load Transient Response Anachip Corp. www.anachip.com.tw Rev.1.0 Aug.27, 2004 6/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Marking Information ( Top View) Logo Part Number 1084 for ADJ 84-VV : 15 for 1.5V 18 for 1.8V 25 for 2.5V 33 for 3.3V 50 for 5V 84-VV YYWWX X Blank: normal L: Lead Free Package YY : Year WW: Nth week X : Internal code ( Optional) (TO252-3L) ( Top View) Logo Part Number VV : 15 for 1.5V 18 for 1.8V 25 for 2.5V 33 for 3.3V 50 for 5V Blank for ADJ 1084-VV YYWWX X Blank: normal L: Lead Free Package YY : Year WW: Nth week X : Internal code ( Optional) (TO220-3L / TO263-3L) Anachip Corp. www.anachip.com.tw Rev.1.0 Aug.27, 2004 7/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator Package Dimension (1) TO263-3L 10.9 L3 3 L 15.7 D 9.1 L2 E 1.3 b b2 2.54 Land Pattern Recommendation (Unit: mm) C2 A C e L1 Symbol A b b2 C C2 D E e L L1 L2 L3 Dimensions In Millimeters Min. Nom. Max. 4.06 4.45 4.83 0.51 0.75 0.99 1.14 1.27 1.40 0.38 TYP. 1.14 1.27 1.40 8.65 9.15 9.65 9.65 9.97 10.29 2.54 BSC. 14.61 15.24 15.88 2.28 2.54 2.80 1.30 2.92 1.27 1.52 1.78 Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.160 0.175 0.190 0.020 0.030 0.039 0.045 0.050 0.055 0.015 TYP. 0.045 0.050 0.055 0.341 0.380 0.380 0.405 0.575 0.360 0.393 0.100 BSC. 0.600 0.090 0.050 0.100 0.051 0.060 0.110 0.115 0.070 0.625 Rev.1.0 Aug.27, 2004 8/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator (2) TO252-3L 5.6 L2 E 7.2 D 11.0 5.6 b2 2.0 2.25 L1 1.2 Land Pattern Recommendation (Unit: mm) e e1 Notes: 1. 2. Symbol A A1 b b2 C C1 D E e e1 H L L1 L2 SEATING PLANE A L SEE NOTE2 A1 C H C1 b JEDEC Outline: TO-252 AB Mils suggested for positive contact at mounting. Dimensions In Millimeters Min. Nom. Max. 2.18 2.29 2.39 1.02 1.15 1.27 0.61 TYP. 5.20 5.35 5.50 0.46 0.52 0.58 0.46 0.52 0.58 5.33 5.57 5.80 6.35 6.58 6.80 2.25 BSC. 4.50 BSC. 9.00 9.70 10.40 0.51 0.64 0.83 1.02 1.52 1.78 2.03 Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.086 0.090 0.094 0.040 0.045 0.050 0.024 TYP. 0.205 0.211 0.217 0.018 0.020 0.023 0.018 0.020 0.023 0.210 0.219 0.228 0.250 0.259 0.268 0.089 BSC. 0.177 BSC. 0.354 0.382 0.409 0.020 0.025 0.033 0.040 0.060 0.070 0.080 Rev.1.0 Aug.27, 2004 9/10 AP1084 5A Low Dropout Positive Adjustable or Fixed-Mode Regulator (3) TO220-3L E A F SEATING PLANE Q ΦP L1 D H1 L b1 C b J1 e e1 Symbol A b1 b C D E e e1 F H1 J1 L L1 øP Q Dimensions In Millimeters Min. Nom. Max. 3.55 4.20 4.85 1.14 1.46 1.78 0.51 0.83 1.14 0.31 0.72 1.14 14.20 15.35 16.50 9.70 10.20 10.70 2.29 2.54 2.79 4.83 5.08 5.33 0.51 0.95 1.40 5.84 6.35 6.86 2.03 2.48 2.92 12.72 13.72 14.72 3.66 5.00 6.35 3.53 3.81 4.09 2.54 2.98 3.43 Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.140 0.165 0.191 0.045 0.057 0.070 0.020 0.033 0.045 0.012 0.028 0.045 0.559 0.604 0.650 0.382 0.402 0.421 0.090 0.100 0.110 0.190 0.200 0.210 0.020 0.037 0.055 0.230 0.250 0.270 0.080 0.098 0.115 0.501 0.540 0.580 0.144 0.197 0.250 0.139 0.150 0.161 0.100 0.117 0.135 Rev.1.0 Aug.27, 2004 10/10