5A Low Dropout Positive Adjustable or Fixed-Mode Regulator AP1084 X X X X. Blank : Adj 15 = 1.5V 18 = 1.8V 25 = 2.5V 33 = 3.3V 50 = 5.0V.

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1 Features.4V maximum dropout at full load current Built-in thermal shutdown Output current limiting Adjustable output voltage or fixed.5v,.8v,.5v, 3.3V, 5.V Fast transient response Good noise rejection Package : TO5, TO63, TO General Description AP84 is a low dropout positive adjustable or fixedmode regulator with minimum of 5.A 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. AP84 is also well suited for other applications such as VGA cards. AP84 is guaranteed to have lower than.4v dropout at full load current making it ideal to provide well-regulated outputs of.5 to 3.3V with 4.7 to V input supply. Ordering Information AP84 X X X X Low Dropout Regulator Package Typical Circuit D : TO5-3L K : TO63-3L T : TO-3L Blank : Adj 5 =.5V 8 =.8V 5 =.5V 33 = 3.3V 5 = 5.V Lead Free Blank : Normal L : Lead Free Package Packing Blank : Tube A : Taping 5.V to 3.3V Fixed Mode Regulator 5V C uf 5V Adjustable Regulator C uf GND Tab is C uf 3.3V/5A Adj Tab is R R Ω Ω R Note: V o = VREF (+ R ) C uf.5v/5a This datasheet contains new product information. 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.. Aug.7, 4

2 Block Diagram CURRENT LIMIT.5V + Thermal Shutdown + - Adj Connection Diagram TO63 FRONT VIEW TO5 FRONT VIEW TO FRONT VIEW 3 Adj (GND) 3 Adj (GND) 3 Adj (GND) Tab is Pin Descriptions Tab is Tab is NAME I/O PIN # FUNCTION Adj (GND) Adjustable (Ground only for fixed mode) O I 3 The output of the regulator. A minimum of uf capacitor must be connected from this pin to ground to insure stability. 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.4v higher than in order for the device to regulate properly. /8 Rev.. Aug.7, 4

3 Absolute Maximum Ratings Symbol Parameter Rating Unit DC Supply Voltage -.3 to V P D Power Dissipation Internally Limited T ST Storage Temperature -65 to +5 o C T OP Operating Junction Temperature Range to +5 o C Electrical Characteristics (Under Operating Conditions) SYM. PARAMETER CONDITIONS (Notes) MIN TYP MAX UNIT V REF Reference Voltage Io=mA, Tj=5 o C, (-)=.5V V AP84-XXX I O=mA, V OUT+.5V<V IN<V, T J =5 o C. % AP84-.5 I OUT = ma, T J = 5 o C, 3V V IN V V Line Regulation Load Regulation AP84-.8 I OUT = ma, T J = 5 o C, 3.3V V IN V V AP84-.5 I OUT = ma, T J = 5 o C, 4V V IN V V AP I OUT = ma, T J = 5 o C, 4.8V V IN V V AP84-5. I OUT = ma, T J = 5 o C, 6.5V V IN V V AP84-Adj V IN=3.3V, ma<io<5a, T J =5 o C (Note,) % AP84-.5 V IN=3V, ma<io<5a, T J =5 o C (Note,) 5 mv AP84-.8 V IN=3.3V, ma<io<5a T J =5 o C (Note,) 5 8 mv AP84-.5 V IN=4V, ma<io<5a T J =5 o C (Note,) 5 mv AP V IN = 5V, ma<io<5a, T J=5 o C (Note,) 6 33 mv AP84-5. V IN = 8V, ma<io<5a, T J=5 o C (Note,) 4 5 mv Vo Dropout Voltage Io=5.A ( = % ).3.4 V Current Limit -=5V 5. A Minimum Load Current 5 ma Temperature Stability Io=mA.5 % θ JA θ JC Thermal Resistance Junction-to-Ambient (No heat sink ;No air flow) Thermal Resistance Junction-to-Case TO-5 TO-63 TO- TO-5: Control Circuitry/Power Transistor TO-63: Control Circuitry/Power Transistor TO-: Control Circuitry/Power Transistor /.7 Note : 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 = /8 from the package. Note :Line and load regulation are guaranteed up to the maximum power dissipation of 5W. 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. O C/W O C/W 3/

4 Functional Description Introduction The AP84 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.5 to 5V. The AP84 only needs.4v differential between and 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 +/- mv including initial tolerance, load regulation and to 5.A load step. The AP84 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 AP84 can be programmed to any voltages in the range of.5v to 5V with the addition of R and R external resistors according to the following formula: = Vref (+ R/R) +Iadj *R, where Vref =.5 typically, Iadj = 55uA typically R&R as shown at below AP84 Adj Vref R Iadj=55uA R The AP84 keeps a constant.5v between the output pin and the adjust pin. By placing a resistor R across these two pins a constant current flows through R, adding to the Iadj current and into the R resistor producing a voltage equal to the (.5/R)*R+Iadj*R which will be added to the.5v to set the output voltage. This is summarized in the above equation. Since the minimum load current requirement of the AP84 is ma, R is typically selected to be Ω 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 R=Ω and R=Ω the error due to Iadj is only.3% of the nominal set point. output voltage at the load. The best load regulation is achieved when the bottom side of R is connected to the load and the top-side of R resistor is connected directly to the case or the 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. Stability The AP84 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 uf aluminum electrolytic capacitor insures both stability and good transient response. Load Regulation Since the AP84 is only a 3 terminal device, it is not possible to provide true remote sensing of the 4/

5 Functional Description (Continued) Thermal Design The AP84 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 5 o C, 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 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 pin to the output capacitors to prevent any high frequency oscillation that may result due to excessive trace inductance. 5/

6 Performance Characteristics Dropout Voltage (V) Tj = 5 o C.. 8 Tj = 5 o C Output Voltage Deviation (%) I load=.5a 3 4 Output Current (A) Dropout Voltage vs Output Current Temperature ( o C) Load Regulation vs Temperature Output Voltage Change (%) Temperature ( o C) Percent Change in Output Voltage vs Temperature Output Voltage Deviation (%) Input Voltage (V) Line Regulation Output Voltage Deviation (mv) Input Voltage (V) 7.5 Cin=uF 6.5 Cout=uF Tantalum TIME (us) Line Transient Response Load Current (A) Output Voltage Deviation (mv) Cin=uF Cout=uF Tantalum Preload=mA TIME (us) Load Transient Response 6/

7 Marking Information ( Top View) Logo Part Number 84 for ADJ 84-VV : 5 for.5v 8 for.8v 5 for.5v 33 for 3.3V 5 for 5V 84-VV YYWWX X Blank: normal L: Lead Free Package YY : Year WW: Nth week X : Internal code ( Optional) (TO5-3L) ( Top View) Logo Part Number VV : 5 for.5v 8 for.8v 5 for.5v 33 for 3.3V 5 for 5V Blank for ADJ 84-VV YYWWX X YY : Year WW: Nth week X : Internal code ( Optional) Blank: normal L: Lead Free Package (TO-3L / TO63-3L) 7/

8 Package Dimension () TO63-3L E L.9 D L e b b L3.3 C A C Land Pattern Recommendation (Unit: mm) L Symbol Dimensions In Millimeters Dimensions In Inches Min. Nom. Max. Min. Nom. Max. A b b C.38 TYP..5 TYP. C D E e.54 BSC.. BSC. L L L L /

9 () TO5-3L E b L 5.6 D L b e e H C A Land Pattern Recommendation (Unit: mm) L SEE NOTE SEATING PLANE C A Notes:. JEDEC Outline: TO-5 AB. Mils suggested for positive contact at mounting. Symbol Dimensions In Millimeters Dimensions In Inches Min. Nom. Max. Min. Nom. Max. A A b.6 TYP..4 TYP. b C C D E e.5 BSC..89 BSC. e 4.5 BSC..77 BSC. H L L L /

10 (3) TO-3L E ΦP A F D SEATING PLANE L L Q H b e e b C J Symbol Dimensions In Millimeters Dimensions In Inches Min. Nom. Max. Min. Nom. Max. A b b C D E e e F H J L L øp Q /

11 This datasheet has been downloaded from: Datasheets for electronic components.

Not Recommended for New Design

Not Recommended for New Design Features.4V maximum dropout at full load current Fast transient response Output current limiting Built-in thermal shutdown Packages: TO22-5, TO252-5, TO263-5, SOP8 Good noise rejection Fixed Output.5V,.8V,