Linear Voltage Regulator

NCP631 3.0 A Linear Voltage Regulator with Soft−Start The NCP631 is a low dropout positive voltage regulator that is capable of providing a guaranteed output current of 3.0 A with a maximum dropout voltage of 1.25 V at 3.0 A over temperature. The NCP631 is currently offered as a fixed voltage version at 3.47 V. On chip trimming adjusts the reference/output voltage to within "1.5% accuracy. The Soft−Start function allows control of start up times. This prevents current spikes at start up due to output capacitor in−rush current. Internal protection features consist of output foldback current limiting, and thermal shutdown. The NCP631 is available in D2PAK package. Features http://onsemi.com 1 5 D2PAK D2T SUFFIX CASE 936A Tab = Ground Pin 1. Shutdown 2. Vin 3. Ground 4. Vout 5. Soft−Start • • • • • • • • • • • • Output Current of 3.0 A 1.25 V Maximum Dropout Voltage at 3.0 A Over Temperature Voltage on Shutdown Pin is TTL compatible Reference/Output Voltage Trimmed to "1.5 % Current Limit Protection Thermal Shutdown Protection 0°C to 125°C Junction Temperature Range Pb−Free Packages are Available www.DataSheet4U.com MARKING DIAGRAM Applications Microprocessor Power Supplies SMPS Post Regulation Battery Chargers DSP Power Supplies NC P631GD2T AWLYWWG 2 INPUT Cin 1 NCP631 3 Shutdown 4 5 Cs Cout Vout 3.47 NCP631GD2T = Device Code A = Assembly Location WL = Wafer Lot Y = Year WW = Work Week G = Pb−Free Package ORDERING INFORMATION Device NCP631GD2TR4 Package D2PAK D2PAK (Pb−Free) NCP631GD2T NCP631GD2TG D2PAK D2PAK (Pb−Free) †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. 50 Units / Tube 50 Units / Tube Shipping† 800/Tape & Reel 800/Tape & Reel Figure 1. Typical Application Circuit NCP631GD2TR4G © Semiconductor Components Industries, LLC, 2006 1 April, 2006 − Rev. 5 Publication Order Number: NCP631/D NCP631 PIN DESCRIPTION Pin No. 1 Symbol Shutdown Description This input is used to place the NCP631 into shutdown mode. The NCP631 is active when a voltage greater than 2.0 V is applied. The NCP631 will be placed into a shutdown mode when a voltage less then 0.8 V is applied. If left unused then connect the pin high. Positive Power Supply Input Voltage Power Supply Ground ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ 2 Vin 3, Tab 4 5 Ground Vout Regulated Output Voltage Soft−Start Soft−Start capacitor is placed from this pin to ground. Refer to applications information section on Page 6 for proper capacitor selection. MAXIMUM RATINGS Rating Symbol Vin Enable Vout Value 9.0 Unit V V V Input Voltage (Note 1) Shutdown Voltage Output Voltage Power Dissipation and Thermal Characteristics Case 936A (D2PAK) Power Dissipation (Note 2) Thermal Resistance, Junction−to−Ambient Thermal Resistance, Junction−to−Case Operating Junction Temperature Range Storage Temperature Range −0.3 to 7 −0.3 to Vin + 0.3 PD RqJA RqJC TJ Tstg Internally Limited 45 5.0 −40 to 125 −55 to 150 W °C/W °C/W °C °C Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. 1. This device series contains ESD protection and exceeds the following tests: Human Body Model JESD 22−A114−B Machine Model JESD 22−A115−A 2. The maximum package power dissipation is: T (max) * TA PD + J RqJA VIN THERMAL SHUTDOWN VOUT + − − + SHUTDOWN − + VREF2 Soft−Start GND VREF1 (Band Gap) ~ 1.25 V Figure 2. Simplified Block Diagram http://onsemi.com 2 NCP631 ELECTRICAL CHARACTERISTICS (Cin = 68 mF, Cout = 47 + 470 mF, Vin = Vout + 1.5 V, Iout = 10 mA, for typical value TJ = 25°C, for min and max values TJ = 0°C to 125°C unless otherwise noted.) Characteristic Output Voltage (Vin = 5.0 V to 7.0 V, Iout = 10 mA to 3.0 A, TJ = 25°C) (Vin = 5.0 V to 7.0 V, Iout = 10 mA to 3.0 A, TJ = 0°C to 125°C) Line Regulation (TJ = 25°C) (Note 3) (Vin = Vout + 1.5 V to 7.0 V) (Vin = Vout + 1.5 V to 7.0 V, TJ = 0°C to 125°C) Load Regulation (TJ = 25°C) (Note 3) (Iout = 10 mA to 3.0 A, TJ = 25°C) (Iout = 10 mA to 3.0 A, TJ = 0°C to 125°C) Dropout Voltage (Measured at Vout – 2%) (Iout = 300 mA) (Iout = 3.0 A) Ground Pin Current in Normal Mode (Iout = 300 mA) (Iout = 3.0 A) Ground Pin Current in Shutdown Mode (Vshutdown < 0.8) Peak Output Limit Internal Current Limitation Thermal Shutdown Shutdown Input Threshold Voltage (Voltage Increasing, Output Turns On, Logic High) (Voltage Decreasing, Output Turns Off, Logic Low) Shutdown Input Low Current (Vin = 0.8 V), (Negative Current Flows out of Pin) Shutdown Input High Current (Vin = 2.0 V), (Negative Current Flows out of Pin) Ripple Rejection (Cout = 100 mF, f = 1.0 kHz) Soft−Start Pin Current Vtth(shutdown) 2.0 − IIL IIH RR − ISS − 76 11 − − mA −10 −10 − − −2.0 −2.0 − 0.8 − − mA mA dB Symbol Vadj 3.418 3.383 Regline − − Regload − − Vin−Vout − − IGnd − − IGnd − Iout 3.0 − − 40 − 5.2 155 75 − − − A A °C V 0.4 1.0 1.0 2.0 mA 0.75 1.0 1.0 1.25 mA 0.01 0.06 − − V 0.02 0.06 − − % 3.470 − 3.522 3.557 % Min Typ Max Unit V 3. Low duty cycle pulse techniques are used during testing to maintain the junction temperature as close to ambient as possible. 4. Line regulation is defined as the change in output voltage for a change in input voltage. Load regulation is defined as the change in output voltage for a change in output load current at a constant temperature. The limits for line and load regulation are contained within the reference voltage specification, Vadj. Typical numbers are included in the specification for line and load regulation. http://onsemi.com 3 NCP631 3.485 Vout, OUTPUT VOLTAGE (V) 3.480 3.475 3.470 3.465 3.460 3.455 3.450 3.445 −40 −15 10 35 60 85 110 130 Isc, SHORT CIRCUIT CURRENT LIMIT (A) 8 7 6 5 4 3 2 1 0 −40 −15 10 35 60 85 110 130 TA, AMBIENT TEMPERATURE (°C) TA, AMBIENT TEMPERATURE (°C) Figure 3. Output Voltage vs. Temperature Figure 4. Short Circuit Limit vs. Temperature 1.2 IGND, GROUND CURRENT (mA) 1.0 Vin − Vout, DROPOUT (V) 0.8 0.6 Iout = 300 mA 0.4 0.2 0 −40 Iout = 3.0 A 1.2 1.0 0.8 0.6 0.4 0.2 0 −40 Iout = 3.0 A Iout = 300 mA −15 10 35 60 85 110 130 −15 10 35 60 85 110 130 TA, AMBIENT TEMPERATURE (°C) TA, AMBIENT TEMPERATURE (°C) Figure 5. Dropout Voltage vs. Temperature 50 IGND, GROUND CURRENT (mA) Figure 6. Ground Current vs. Temperature 40 30 Vshutdown = 0 V 20 10 0 −40 −15 10 35 60 85 110 130 TA, AMBIENT TEMPERATURE (°C) Figure 7. Ground Pin Current in Shutdown Mode vs. Temperature http://onsemi.com 4 NCP631 1.200 1.000 NOISE VALUE (mV) 0.800 0.600 0.400 0.200 0.000 1 10 100 1,000 10,000 100,000 1,000,000 f, FREQUENCY (Hz) 120 100 80 40 40 20 0 10 Vin = 5.0 V + 0.5 Vpp Cout = 100 mF, Al Electrolytic Iout = 10 mA Vin = 4.47 V Cout = 33 mF Cin = 100 mF Iout = 10 mA RIPPLE REJECTION (dB) 100 1,000 f, FREQUENCY (Hz) 10,000 100,000 Figure 8. Noise Characterization Figure 9. Ripple Rejection vs. Frequency Vin, INPUT VOLTAGE (V) 7 6 5 Vin, INPUT VOLTAGE (V) Cin = 68 mF, Al Electrolytic Cout = 33 mF, Al Electrolytic Iout = 200 mA OUTPUT VOLTAGE DEVIATION (mV) 7 6 5 OUTPUT VOLTAGE DEVIATION (mV) 50 40 30 20 10 0 0 100 200 300 TIME (mS) 400 500 600 60 40 20 0 Cin = 1.0 mF Cout = 33 mF, Al Electrolytic Iout = 200 mA −20 −40 0 10 20 30 TIME (mS) 40 50 60 Figure 10. Line Transient Figure 11. Line Transient Iout, OUTPUT CURRENT (A) 4.5 3.0 1.5 Iout = 100 mA to 3.0 A 0 OUTPUT VOLTAGE DEVIATION (mV) 0 −50 −100 −150 0 10 20 Cin = 68 mF, Al Electrolytic Cout = 33 mF, Al Electrolytic Vin = 5.0 V 30 TIME (mS) 40 50 60 Figure 12. Load Transient http://onsemi.com 5 NCP631 APPLICATIONS INFORMATION Input Capacitor The minimum capacitance required for stability is a 68 mF aluminum electrolytic or tantalum capacitor. The maximum ESR allowed for stability is 5.0 W. The capacitor should be place as close as possible to the input of the device. The placement of a ceramic capacitor in parallel is not recommend due to possible instabilities. Output Capacitor Where: Iss + 11 mA Cs + 10 nF (typ) Vref + 1.2 V Vout + 3.47 V (eq. 2) Output current limitation during start−up: V Iout + out * Cout * Iss Vref Cs (eq. 3) A minimum output capacitor value of 33 mF is required for stability. The type of capacitor can be aluminum electrolytic or tantalum capacitor. ESR can vary up to a maximum of 2.0 W for stability. The capacitor should be placed as close as possible to the output of the device. The placement of a ceramic capacitor in parallel is not recommend due to possible instabilities. Soft−Start Function An example for Cout = 500 mF, Cs = 10 nF: Iout + 3.47 * 500E * 6 * 11E * 6 + 1.59 A (eq. 4) 1.2 10E * 9 Time when the output voltage will reach target value can be determined by: Ts + Vref * Cs Iss (