FAN1084MC15

www.fairchildsemi.com FAN1084 4.5A Adjustable/Fixed Low Dropout Linear Regulator Features • • • • • Fast transient response Low dropout voltage at up to 4.5A Load regulation: 0.5% typical On-chip thermal limiting Standard TO-220, TO-263 center cut, and TO-252 packages Description The FAN1084, FAN1084-1.5, and FAN1084-3.3 are low dropout three-terminal regulators with 4.5A output current capability. These devices have been optimized for low voltage applications including VTT bus termination, where transient response and minimum input voltage are critical. The FAN1084 is ideal for low voltage microprocessor applications requiring a regulated output from 1.5V to 3.6A with an input supply of 5V or less. The FAN1084-1.5 offers fixed 1.5V with 4.5A current capabilities for GTL+ bus VTT termination. The FAN1084-3.3 offers a fixed 3.3V output at 4.5A. On-chip thermal limiting provides protection against any combination of overload and ambient temperature that would create excessive junction temperatures. The FAN1084 series regulators are available in the industrystandard TO-220, TO-263 center cut, and TO-252 (DPAK) power packages. Applications • • • • • • • Desktop PCs, RISC and embedded processors’ supply GTL, SSTL logic Reference bus supply Low voltage VCC logic supply Battery-powered circuitry Post regulator for switching supply Cable and ADSL modems’ DSP core supply Set Top Boxes and Web Boxes modules’ supply Application Diagrams VIN = 5V 10µF + VIN FAN1084 VOUT ADJ 124Ω + 2.5V at 4.5A 22µF 124Ω VIN = 3.3V 10µF + FAN1084-1.5 VIN VOUT GND + 1.5V at 4.5A 22µF REV. 1.0.8 11/10/03 FAN1084 PRODUCT SPECIFICATION Pin Assignments FAN1084T FRONT VIEW FAN1084T-3.3 FAN1084T-1.5 FRONT VIEW FAN1084M-3.3† FAN1084M-1.5 FRONT VIEW FAN1084M FRONT VIEW Tab is out. FAN1084D-3.3 FAN1084D-1.5 FAN1084D FRONT VIEW FRONT VIEW 1 Tab is out. 123 123 2 3 1 2 3 1 2 3 1 2 3 GND GND IN ADJ IN IN ADJ IN ADJ OUT IN GND OUT IN 3-Lead Plastic TO-263 ΘJC=3°C/W* 3-Lead Plastic TO-252 ΘJC=3°C/W* 3-Lead Plastic TO-220 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 may provide better power dissipation than 30°C/W. † FAN1084M-3.3 also available with uncut center lead. Absolute Maximum Ratings Parameter VIN Operating Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 seconds) 0 –65 Min. Max. 7 125 150 300 Unit V °C °C °C 2 REV. 1.0.8 11/10/03 PRODUCT SPECIFICATION FAN1084 Electrical Characteristics Operating Conditions: 4.75 ≤ VIN < 5.25V, Tj = 25°C unless otherwise specified. Parameter Reference Voltage Output Voltage5 Output Voltage 6 3 Conditions Adj connected to ground, IOUT = 10mA IOUT = 10mA IOUT = 10mA IOUT = 10mA 10mA ≤ IOUT ≤ 4.5A ∆VREF% = 2%, IOUT = 4.5A (VIN – VOUT) = 2V Min. 1.23 1.475 3.234 Typ. 1.250 1.5 3.3 0.5 0.5 Max 1.27 1.525 3.366 2 2.5 1.5 Units V V V % % V A Line Regulation1, 2 Load Regulation1, 2 Dropout Voltage Current Limit Adjust Pin Current3 Mimimum Load Current4 5.5 35 100 µΑ mA mA °C/W °C/W °C 1.5V ≤ (VIN – VOUT) ≤ 5.75V VIN = 5V TO-220 TO-263 Center Cut, TO-252 10 4 3 3 150 Quiescent Current4 Thermal Resistance, Junction to Case Thermal Shutdown4 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. FAN1084 only. 4. Guaranteed by design. 5. FAN1084-1.5 only. 6. FAN1084-3.3 only. Typical Performance Characteristics 20 POWER (W) 15 10 5 0 25 45 65 85 105 125 CASE TEMPERATURE Figure 1. Maximum Power Dissipation REV. 1.0.8 11/10/03 3 FAN1084 PRODUCT SPECIFICATION Typical Performance Characteristics (Continued) 1.5 1.4 DROPOUT VOLTAGE (V) 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0 1 2 3 4 5 6 OUTPUT CURRENT (A) T=0°C T=25°C T=125°C ∆I = 4.5A Figure 2. Dropout Voltage vs. Output Current Figure 3. Load Regulation vs. Temperature 1.275 1.270 1 OUT VOUT = 3.6V 1 REFERENCE VOLTAGE (V) 1.265 1.260 1.255 1.250 1.245 1.240 1.235 1.230 1.225 -75 -50 -25 0 25 50 75 100 125 150 175 VOUT = 3.3V 1 JUNCTION TEMPERATURE (°C) Figure 4. Reference Voltage vs. Temperature Figure 5. Output Voltage vs. Temperature 5 MINIMUM LOAD CURRENT (mA) 4 3 2 1 0 -75 -50 -25 0 25 50 75 100 125 150 175 JUNCTION TEMPERATURE (°C) Figure 6. Minimum Load Current vs. Temperature Figure 7. Adjust Pin Current vs. Temperature 4 REV. 1.0.8 11/10/03 PRODUCT SPECIFICATION FAN1084 Typical Performance Characteristics (continued) 8.0 SHORT-CIRCUIT CURRENT (A) 90 80 RIPPLE REJECTIONS (dB) 7.0 70 60 50 40 30 20 10 (VIN – VOUT) ≤ 3V 0.5V ≤ VRIPPLE ≤ 2V IOUT = 5A 100 1K FREQUENCY (Hz) 10K 100K 6.0 5.0 4.0 -75 -50 -25 0 25 50 75 100 125 150 175 0 10 JUNCTION TEMPERATURE (°C) Figure 8. Short-Circuit Current vs. Temperature 2.5 OUTPUT CAPACITANCE ESR, (Ω) Figure 9. Ripple Rejection vs. Frequency 2 1.5 Area of Instability 1 0.5 Stable Area 0 0 1000 2000 3000 4000 LOAD CURRENT (mA) Figure 10. Stability Region VIN/VOUT = 5V/1.5V REV. 1.0.8 11/10/03 5 FAN1084 PRODUCT SPECIFICATION Applications Information General The FAN1084, FAN1084-1.5, and FAN1084-3.3 are threeterminal 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 FAN1084 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+. The adjust pin can be driven on a transient basis ±7V with respect to the ouput, without any device degradation. As with any IC regulator, exceeding the maximum input-to-output voltage differential causes the internal transistors to break down and none of the protection circuitry is then functional. D1 1N4002 (OPTIONAL) FAN1084 VIN + IN C1 10µF ADJ + CADJ OUT R1 + VOUT C2 22µF Stability The FAN1084 series requires an output capacitor as a part of the frequency compensation. It is recommended to use a 22µF solid tantalum or a 100µF 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