www.fairchildsemi.com FAN1585A 5A Adjustable/Fixed Low Dropout Linear Regulator Features Description • • • • • • The FAN1585A, FAN1585A-1.5, and FAN1585A-1.8 are low dropout three-terminal regulators with 5A output current capability. These devices have been optimized for low voltage applications including VTT bus termination for FC-PGA, where transient response and minimum input voltage are critical. The FAN1585A-1.5 offers fixed 1.5V with 5A current capabilities for AGTL+ bus VTT termination for FC-PGA. The FAN1585A is ideal for low voltage microprocessor applications requiring a regulated output from 1.5V to 3.6V with an input supply of 5V or less, or for FC-PGA applications with significant trace resistance. Fast transient response Low dropout voltage at up to 5A Load regulation: 0.05% typical Trimmed current limit On-chip thermal limiting Packages: TO-220, TO-252, TO-263 and TO-263 Centercut Applications • • • • • AGTL+ bus supply for FC-PGA Low voltage logic supply Post regulator for switching supply 3.3V to 1.5V linear regulator 5V to 1.8V linear regulator Current limit is trimmed to ensure specified output current and controlled short-circuit current. On-chip thermal limiting provides protection against any combination of overload and ambient temperature that would create excessive junction temperatures. The FAN1585A series regulators are available in the industrystandard TO-220, TO-252, TO-263 and TO-263 Centercut power packages. Typical Applications FAN1585A VOUT VIN VIN = 3.3V 22µF + ADJ 1.5V at 5A + R1 124Ω 22µF R2 24.9Ω VOUT = VREF(1 + R2/R1) + IAdj • R2 FAN1585A-1.5 VIN VOUT VIN = 3.3V + 22µF GND 1.5V at 5A + 22µF REV. 1.1.6 7/8/05 FAN1585A PRODUCT SPECIFICATION Pin Assignments FRONT VIEW 1 2 FRONT VIEW FRONT VIEW FRONT VIEW Tab is VOUT Tab is Out. 3 Tab is Out. 1 1 ADJ/ OUT IN GND 2 ADJ/ OUT GND 3-Lead Plastic TO-220 θJC = 3°C/W 2 Tab is Out. 1 3 2 3 3 ADJ/ GND ADJ/ OUT IN GND IN 3-Lead Plastic TO-252 θJC = 3°C/W IN 3-Lead Plastic TO-263 Center Cut θJC = 3°C/W* 3-Lead Plastic TO-263 θJC = 3°C/W* *With package soldered to 0.5 square inch copper area over backside ground plane or internal power plane, θJA can vary from 30°C/W to more than 40°C/W. Other mounting techniques can provide a thermal resistance lower than 30°C/W. Absolute Maximum Ratings Parameter Min. Max. Unit 18 V 0 125 °C -65 150 °C 300 °C VIN Operating Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 sec.) 7 6 IOUT (Amps) 5 4 3 2 1 0 0 2 4 6 8 10 12 14 VIN–VOUT (V) Absolute Maximum Safe Operating Area 2 REV. 1.1.6 7/8/05 PRODUCT SPECIFICATION FAN1585A Electrical Characteristics Tj = 25°C unless otherwise specified. The • denotes specifications which apply over the specified operating temperature range. Parameter Conditions 3 Min. Typ. Max Units Reference Voltage 1.5V ≤ (VIN – VOUT) ≤ 5.75V, 10mA ≤ IOUT ≤ 5A • 1.225 (-2%) 1.250 1.275 (+2%) V Output Voltage4 3.0V ≤ VIN ≤ 8V 10mA ≤ IOUT ≤ 5A • 1.47 1.5 1.53 V Output Voltage5 3.3V ≤ VIN ≤ 8.3V 10mA ≤ IOUT ≤ 5A • 1.764 1.8 1.836 V Line Regulation1, 2 (VOUT + 1.5V) ≤ VIN ≤ 12V, IOUT = 10mA • 0.005 0.2 % Load Regulation1, 2, 3 (VIN – VOUT) = 3V, 10mA ≤ IOUT ≤ 5A • 0.05 0.5 % Dropout Voltage ∆VREF = 1%, IOUT = 5A • 1.150 1.300 Current Limit (VIN – VOUT) = 2V • Adjust Pin Current3 Adjust Pin Current Change3 5.1 5.9 V A • 35 120 µA 1.5V ≤ (VIN – VOUT) ≤ 5.75V, 10mA ≤ IOUT ≤ 5A • 0.2 5 µA 4 13 Minimum Load Current 1.5V ≤ (VIN – VOUT) ≤ 12V • Quiescent Current VIN = 5V • Ripple Rejection f = 120Hz, COUT = 22µF Tantalum, (VIN – VOUT) = 3V, IOUT = 5A Thermal Regulation TA = 25°C, 30ms pulse 60 mA 72 0.004 • Temperature Stability 10 mA dB 0.02 0.5 %/W % Long-Term Stability TA = 125°C, 1000 hrs. 0.03 RMS Output Noise (% of VOUT) TA = 25°C, 10Hz ≤ f ≤ 10kHz 0.003 % Thermal Resistance, Junction to Case TO-220, TO-252, TO-263, and TO-263 CC 3 °C/W 150 °C Thermal Shutdown 1.0 % Notes: 1. See thermal regulation specifications for changes in output voltage due to heating effects. Load and line regulation are measured at a constant junction temperature by low duty cycle pulse testing. 2. Line and load regulation are guaranteed up to the maximum power dissipation. Power dissipation is determined by input/ output differential and the output currrent. Guaranteed maximum output power will not be available over the full input/output voltage range. 3. FAN1585A only. 4. FAN1585A-1.5 only. 5. FAN1585A-1.8 only. REV. 1.1.6 7/8/05 3 FAN1585A PRODUCT SPECIFICATION Typical Performance Characteristics 1.5 0.10 OUTPUT VOLTAGE DEVIATION (%) DROPOUT VOLTAGE (V) 1.4 1.3 1.2 1.1 1.0 T=0°C 0.9 T=125°C T=25°C 0.8 0.7 0.6 0.05 0 -0.05 -0.10 -0.15 -0.20 -75 -50 -25 0.5 0 1 2 3 4 5 6 1.275 3.70 1.270 3.65 1.265 3.60 VOUT set with 1% Resistors 1.260 1.255 1.250 1.245 1.240 1.235 1 VOUT = 3.6V 3.55 3.50 3.45 3.40 3.35 3.30 1.230 1 VOUT = 3.3V Note: 1. FAN1585A Only 3.25 1.225 -75 -50 -25 0 3.20 -75 -50 -25 25 50 75 100 125 150 175 JUNCTION TEMPERATURE (°C) Figure 3. Reference Voltage vs. Temperature 0 25 50 75 100 125 150 175 JUNCTION TEMPERATURE (°C) Figure 4. Output Voltage vs. Temperature 5 100 Note: 1. FAN1585A Only 90 ADJUST PIN CURRENT (µA) MINIMUM LOAD CURRENT (mA) 25 50 75 100 125 150 175 Figure 2. Load Regulation vs. Temperature REFERENCE VOLTAGE (V) REFERENCE VOLTAGE (V) 0 JUNCTION TEMPERATURE (°C) OUTPUT CURRENT (A) Figure 1. Dropout Voltage vs. Output Current ∆I = 5A 4 3 2 1 80 70 60 50 40 30 20 10 0 -75 -50 -25 0 25 50 75 100 125 150 175 JUNCTION TEMPERATURE (°C) Figure 5. Minimum Load Current vs. Temperature 4 0 -75 -50 -25 0 25 50 75 100 125 150 175 JUNCTION TEMPERATURE (°C) Figure 6. Adjust Pin Current vs. Temperature REV. 1.1.6 7/8/05 PRODUCT SPECIFICATION FAN1585A Typical Performance Characteristics (continued) 90 8.0 RIPPLE REJECTIONS (dB) SHORT-CIRCUIT CURRENT (A) 80 7.0 6.0 5.0 70 60 50 40 30 (VIN – VOUT) ≤ 3V 0.5V ≤ VRIPPLE ≤ 2V IOUT = 5A 20 10 4.0 -75 -50 -25 0 0 10 25 50 75 100 125 150 175 100 Figure 7. Short-Circuit Current vs. Temperature 100K 2.5 OUTPUT CAPACITANCE ESR, (Ω) POWER (W) 10K Figure 8. Ripple Rejection vs. Frequency 20 15 10 5 0 50 60 70 80 90 100 110 120 130 140 150 CASE TEMPERATURE (°C) Figure 9. Maximum Power Dissipation REV. 1.1.6 7/8/05 1K FREQUENCY (Hz) JUNCTION TEMPERATURE (°C) 2 1.5 Area of Instability 1 0.5 Stable Area 0 0 1000 2000 3000 4000 5000 LOAD CURRENT (mA) Figure 10. Stability Region VIN/VOUT = 5V/1.5V 5 FAN1585A PRODUCT SPECIFICATION Applications Information General The FAN1585A and FAN1585A-1.5 are three-terminal regulators optimized for GTL+ VTT termination and logic applications. These devices are short-circuit protected and offer thermal shutdown to turn off the regulator when the junction temperature exceeds about 150°C. The FAN1585A series provides low dropout voltage and fast transient response. Frequency compensation uses capacitors with low ESR while still maintaining stability. This is critical in addressing the needs of low voltage high speed microprocessor buses like GTL+. break down and none of the protection circuitry is then functional. D1 1N4002 (OPTIONAL) FAN1585A VIN Stability The FAN1585A series requires an output capacitor as a part of the frequency compensation. It is recommended to use a 22µF solid tantalum or a 100 µF aluminum electrolytic on the output to ensure stability. The frequency compensation of these devices optimizes the frequency response with low ESR capacitors. In general, it is suggested to use capacitors with an ESR of <300mΩ. It is also recommended to use bypass capacitors such as a 22µF tantalum or a 100µF aluminum on the adjust pin of the FAN1585A for low ripple and fast transient response. When these bypassing capacitors are not used at the adjust pin, larger values of output capacitors provide equally good results. Refer to Typical Performance Characteristics for graph of stability of output capacitance ESR vs load current. + C1 22µF IN OUT ADJ + R1 VOUT C2 22µF + CADJ R2 D1 1N4002 (OPTIONAL) FAN1585A-1.5 VIN C1 22µF IN + OUT GND + VOUT C2 22µF Figure 10. Optional Protection Protection Diodes Ripple Rejection In normal operation, the FAN1585A series does not require any protection diodes. For the FAN1585A, internal resistors limit internal current paths on the adjust pin. Therefore, even with bypass capacitors on the adjust pin, no protection diode is needed to ensure device safety under short-circuit conditions. In applications that require improved ripple rejection, a bypass capacitor from the adjust pin of the FAN1585A to ground reduces the output ripple by the ratio of VOUT/1.25V. The impedance of the adjust pin capacitor at the ripple frequency should be less than the value of R1 (typically in the range of 100Ω to 120Ω) in the feedback divider network in Figure 10. Therefore, the value of the required adjust pin capacitor is a function of the input ripple frequency. For example, if R1 equals 100Ω and the ripple frequency equals 120Hz, the adjust pin capacitor should be 22µF. At 10kHz, only 0.22µF is needed. A protection diode between the input and output pins is usually not needed. An internal diode between the input and the output pins on the FAN1585A series can handle microsecond surge currents of 50A to 100A. Even with large value output capacitors it is difficult to obtain those values of surge currents in normal operation. Only with large values of output capacitance, such as 1000µF to 5000µF, and with the input pin instantaneously shorted to ground can damage occur. A crowbar circuit at the input can generate those levels of current; a diode from output to input is then recommended, as shown in Figure 10. Usually, normal power supply cycling or system “hot plugging and unplugging” will not generate current large enough to do any damage. The adjust pin can be driven on a transient basis ±7V with respect to the output, without any device degradation. As with any IC regulator, exceeding the maximum input-tooutput voltage differential causes the internal transistors to 6 Output Voltage The FAN1585A regulator develops a 1.25V reference voltage between the output pin and the adjust pin (see Figure 11). Placing a resistor R1 between these two terminals causes a constant current to flow through R1 and down through R2 to set the overall output voltage. Normally, this current is the specified minimum load current of 10mA. The current out of the adjust pin adds to the current from R1 and is typically 35µA. Its output voltage contribution is small and only needs consideration when a very precise output voltage setting is required. REV. 1.1.6 7/8/05 PRODUCT SPECIFICATION FAN1585A FAN1585A VIN IN + OUT C1 22µF ADJ + VREF IADJ 35µA R1 FAN1585A VOUT VIN C2 22µF IN RP PARASITIC LINE RESISTANCE OUT ADJ R1* R2 RL VOUT = VREF (1 + R2/R1) + IADJ (R2) * CONNECT R1 TO CASE CONNECT R2 TO LOAD Figure 11. Basic Regulator Circuit R2* Load Regulation It is not possible to provide true remote load sensing because the FAN1585A series are three-terminal devices. Load regulation is limited by the resistance of the wire connecting the regulators to the load. Load regulation per the data sheet specification is measured at the bottom of the package. For fixed voltage devices, negative side sensing is a true Kelvin connection with the ground pin of the device returned to the negative side of the load. This is illustrated in Figure 12. FAN1585A-1.5 VIN IN RP PARASITIC LINE RESISTANCE OUT Figure 13. Connection for Best Load Regulation Thermal Considerations The FAN1585A series protect themselves under overload conditions with internal power and thermal limiting circuitry. However, for normal continuous load conditions, do not exceed maximum junction temperature ratings. It is important to consider all sources of thermal resistance from junction-to-ambient. These sources include the junction-to-case resistance, the case-to-heat sink interface resistance, and the heat sink resistance. Thermal resistance specifications have been developed to more accurately reflect device temperature and ensure safe operating temperatures. GND RL For example, look at using an FAN1585AT to generate 5A @ 1.5V ± 2% from a 3.3V source (3.2V to 3.6V). Assumptions: Figure 12. Connection for Best Load Regulation For adjustable voltage devices, negative side sensing is a true Kelvin connection with the bottom of the output divider returned to the negative side of the load. The best load regulation is obtained when the top of the resistor divider R1 connects directly to the regulator output and not to the load. Figure 13 illustrates this point. If R1 connects to the load, then the effective resistance between the regulator and the load would be: RP x (1 + R2/R1), RP = Parasitic Line Resistance The connection shown in Figure 13 does not multiply RP by the divider ratio. As an example, RP is about four milliohms per foot with 16-gauge wire. This translates to 4mV per foot at 1A load current. At higher load currents, this drop represents a significant percentage of the overall regulation. It is important to keep the positive lead between the regulator and the load as short as possible and to use large wire or PC board traces. REV. 1.1.6 7/8/05 • • • • • VIN = 3.6V worst case VOUT = 1.46V worst case IOUT = 5A continuous TA = 50°C θCase-to-Ambient = 3°C/W (assuming both a heatsink and a thermally conductive material) The power dissipation in this application is: PD = (VIN – VOUT) * (IOUT) = (3.6 – 1.46) * (5) = 10.7W From the specification table: TJ = TA + (PD) * (θCase-to-Ambient + θJC) = 50 + (10.7) * (3 + 3) = 115°C The junction temperature is below the maximum rating. 7 FAN1585A PRODUCT SPECIFICATION Junction-to-case thermal resistance is specified from the IC junction to the bottom of the case directly below the die. This is the lowest resistance path for heat flow. Proper mounting ensures the best thermal flow from this area of the package to the heat sink. Use of a thermally conductive material at the case-to-heat sink interface is recommended. Use a thermally conductive spacer if the case of the device must be electrically isolated and include its contribution to the total thermal resistance. The cases of the FAN1585A series are directly connected to the output of the device. U1 FAN1585A VIN 3.3V C1 22µF + VOUT 1.5V VOUT VIN R1 124Ω ADJ + + C3 100µF R2 24.9Ω C2 100µF Figure 14. Application Circuit (FAN1585A) Table 1. Bill of Materials for Application Circuit for the FAN1585A Item Quantity Manufacturer Part Number C1 1 Xicon L10V22 22µF, 10V Aluminum C2, C3 2 Xicon L10V100 100µF, 10V Aluminum R1 1 Generic 124Ω, 1% R2 1 Generic 24.9Ω, 1% U1 1 Fairchild FAN1585AT U1 FAN1585A-1.5 VIN 3.3V VIN C1 22µF Description + VOUT 1.5V VOUT GND + 5A Regulator C3 100µF Figure 15. Application Circuit (FAN1585A-1.5) Table 2. Bill of Materials for Application Circuit for the FAN1585A-1.5 Item Quantity Manufacturer Part Number C1 1 Xicon L10V22 22µF, 10V Aluminum C3 1 Xicon L10V100 100µF, 10V Aluminum U1 1 Fairchild FAN1585AT-1.5 8 Description 5A Regulator REV. 1.1.6 7/8/05 PRODUCT SPECIFICATION FAN1585A Mechanical Dimensions 3-Lead TO-263 Package Symbol Inches Millimeters Notes Min. Max. Min. Max. A b b2 c2 D E e .160 .020 .190 .036 4.06 0.51 4.83 0.91 L L1 L2 R α .575 .090 — .017 0° .049 .051 .045 .055 .340 .380 .380 .405 .100 BSC .625 .110 .055 .019 8° 1.25 1.30 1.14 1.40 8.64 9.65 9.65 10.29 2.54 BSC 14.61 2.29 — 0.43 0° Notes: 1. Dimensions are exclusive of mold flash and metal burrs. 2. Standoff-height is measured from lead tip with ref. to Datum -B-. 3. Foot length is measured with ref. to Datum -A- with lead surface (at inner R). 4. Dimensiuon exclusive of dambar protrusion or intrusion. 5. Formed leads to be planar with respect to one another at seating place -C-. 15.88 2.79 1.40 0.78 8° E @PKG/ @HEATSINK L2 c2 D E-PIN L R (2 PLCS) b2 L1 b e -B- -A- A -C- REV. 1.1.6 7/8/05 9 FAN1585A PRODUCT SPECIFICATION Mechanical Dimensions (continued) 3-Lead TO-263 Center Cut Package Symbol Inches Millimeters Notes Min. Max. Min. Max. A b b2 c2 D E e .160 .020 .190 .036 4.06 0.51 4.83 0.91 L L1 L2 .575 .090 — .050 .017 0° .049 .051 .045 .055 .340 .380 .380 .405 .100 BSC L3 R α .625 .110 .055 .070 .019 8° 1.25 1.30 1.14 1.40 8.64 9.65 9.65 10.29 2.54 BSC 14.61 2.29 — 1.27 0.43 0° Notes: 1. Dimensions are exclusive of mold flash and metal burrs. 2. Standoff-height is measured from lead tip with ref. to Datum -B-. 3. Foot length is measured with ref. to Datum -A- with lead surface (at inner R). 4. Dimensiuon exclusive of dambar protrusion or intrusion. 5. Formed leads to be planar with respect to one another at seating place -C-. 15.88 2.79 1.40 1.78 0.78 8° E @PKG/ @HEATSINK L2 c2 D E-PIN L R (2 PLCS) b2 L1 L3 b e -B- -A- A -C- 10 REV. 1.1.6 7/8/05 PRODUCT SPECIFICATION FAN1585A Mechanical Dimensions (continued) 3-Lead TO-220 Package Inches Symbol Min. A b b1 c1 øP D E e Millimeters Max. Min. .140 .190 .015 .040 .045 .070 .014 .022 .139 .161 .560 .650 .380 .420 .090 .110 .190 .210 .045 — .020 .055 .230 .270 .060 .115 .500 .580 .250 BSC .100 .135 3° 7° e1 e3 F H1 J1 L L1 Q α Notes Max. 3.56 4.83 .38 1.02 1.14 1.78 .36 .56 3.53 4.09 14.22 16.51 9.65 10.67 2.29 2.79 4.83 5.33 1.14 — .51 1.40 5.94 6.87 2.04 2.92 12.70 14.73 6.35 BSC 2.54 3.43 3° 7° Notes: 1. Dimension c1 apply for lead finish. H1 Q L e3 b1 e e1 E b L1 E-PIN øP α (5X) c1 A J1 D REV. 1.1.6 7/8/05 F 11 FAN1585A PRODUCT SPECIFICATION Mechanical Dimensions (continued) 3-Lead TO-252 Package A 6.73 6.35 5.46 5.21 6.00 MIN L3 4 6.50 MIN D 6.25 1.02 0.84 C 1 3.00 MIN 2 3 1 1.14 0.78 (0.59) 0.89 0.54 2.30 1.40 MIN 4.80 2.29 4.57 0.25 M A M C 3 LAND PATTERN RECOMMENDATION B 2.38 2.18 SEE NOTE D E1 0.58 0.48 4 D1 10.41 9.40 SEE DETAIL A 2 3 1 0.10 B 0.61 0.48 (1.54) 10° 0° 1.78 1.40 0.127 MAX 2.90 SEATING PLANE DETAIL A (ROTATED –90° SCALE 12X 12 NOTES: UNLESS OTHERWISE SPECIFIED A) ALL DIMENSIONS ARE IN MILLIMETERS. B) THIS PACKAGE CONFORMS TO JEDEC, TO-252, ISSUE C. VARIATION AA & AB, DATED NOV. 1999. 0.51 GAGE PLANE C) DIMENSIONING AND TOLERANCING PER ASME Y14.5–1994. D) HEAT SINK TOP EDGE COULD BE IN CHAMFERED CORNERS OR EDGE PROTRUSION. E) DIMENSIONS L3, D, E1 & D1 TABLE: OPTION AA OPTION AB L3 0.89 – 1.27 1.52 – 2.03 D 5.97 – 6.22 5.33 – 5.59 E1 4.32 MIN 3.81 MIN D1 5.21 MIN 4.57 MIN REV. 1.1.6 7/8/05 FAN1585A PRODUCT SPECIFICATION Ordering Information Product Number Package FAN1585AMX TO-263 in Tape and Reel FAN1585AMCX TO-263 Center Cut in Tape and Reel FAN1585AT TO-220 FAN1585AM15X TO-263 in Tape and Reel FAN1585AMC15X TO-263 Center Cut in Tape and Reel FAN1585AT15 TO-220 FAN1585AM18X TO-263 in Tape and Reel FAN1585AMC18X TO-263 Center Cut in Tape and Reel FAN1585AT18 TO-220 FAN1585AD TO-252 FAN1585ADX TO-252 in Tape and Reel DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, or (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in significant injury to the user. 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 7/8/05 0.0m 001 Stock#DS30001585 2005 Fairchild Semiconductor Corporation