Low Dropout Linear Regulator

NCP566 1.5 A Low Dropout Linear Regulator The NCP566 low dropout linear regulator will provide 1.5 A at a fixed output voltage. The fast loop response and low dropout voltage make this regulator ideal for applications where low voltage and good load transient response are important. Device protection includes current limit, short circuit protection, and thermal shutdown. Features http://onsemi.com MARKING DIAGRAMS AYM 566xx G G 1 xx = Voltage Rating 12 = 1.2 V 18 = 1.8 V 25 = 2.5 V A = Assembly Location Y = Year M = Date Code G = Pb−Free Package (Note: Microdot may be in either location) www.DataSheet4U.com • • • • • Ultra Fast Transient Response (t1.0 ms) Low Ground Current (1.5 mA @ Iout = 1.5 A) Low Dropout Voltage (0.9 V @ Iout = 1.5 A) Low Noise (37 mVrms) 1.2 V, 1.8 V, 2.5 V Fixed Output Versions. Other Fixed Voltages Available on Request • Current Limit Protection • Thermal Shutdown Protection • These are Pb−Free Devices Typical Applications SOT−223 CASE 318E • • • • Servers ASIC Power Supplies Post Regulation for Power Supplies Constant Current Source PIN CONNECTIONS Vin GND Vout 1 2 3 GND ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 9 of this data sheet. © Semiconductor Components Industries, LLC, 2007 1 March, 2007 − Rev. 0 Publication Order Number: NCP566/D NCP566 PIN DESCRIPTION Pin No. 1 Symbol Vin Description Positive Power Supply Input Voltage Power Supply Ground ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á 2, Tab 3 Ground Vout Regulated Output Voltage MAXIMUM RATINGS Rating Symbol Vin Vout RqJA RqJP TJ TA Tstg Value 9.0 Unit V V Input Voltage (Note 1) Output Pin Voltage Thermal Characteristics (Notes 2, 3) Thermal Resistance, Junction−to−Ambient Thermal Resistance, Junction−to−Pin Operating Junction Temperature Range Operating Ambient Temperature Range Storage Temperature Range −0.3 to Vin + 0.3 107 12 −40 to 150 −40 to 125 −55 to 150 °C/W °C °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: TJ(max) * TA PD + RqJA 3. As measured using a copper heat spreading area of 50 mm2, 1 oz copper thickness. Vin Cin 150mF Voltage Vref = 0.9 V Reference Output Block Stage R1 R2 Vout Cout 150mF GND GND Figure 1. Typical Schematic http://onsemi.com 2 NCP566 ELECTRICAL CHARACTERISTICS (Vin = Vout + 1.6 V, for typical values TJ = 25°C, for min/max values TJ = −40°C to +125°C, Cin = Cout = 150 mF unless otherwise noted.) Characteristic Output Voltage (10 mA < Iout < 1.5 A; 2.8 V < Vin < 9.0 V; TJ = −10 to 105°C) 1.2 V version Output Voltage (10 mA < Iout < 1.5 A; 2.8 V < Vin < 9.0 V; TJ = −40 to 125°C) 1.2 V version Output Voltage (10 mA < Iout < 1.5 A; 3.4 V < Vin < 9.0 V; TJ = −10 to 105°C) 1.8 V version Output Voltage (10 mA < Iout < 1.5 A; 3.4 V < Vin < 9.0 V; TJ = −40 to 125°C) 1.8 V version Output Voltage (10 mA < Iout < 1.5 A; 4.1 V < Vin < 9.0 V; TJ = −10 to 105°C) 2.5 V version Output Voltage (10 mA < Iout < 1.5 A; 4.1 V < Vin < 9.0 V; TJ = −40 to 125°C) 2.5 V version Line Regulation (Iout = 10 mA) Load Regulation (10 mA < Iout < 1.5 A) Dropout Voltage (Iout = 1.5 A) (Note 4) Current Limit Ripple Rejection (120 Hz; Iout = 1.5 A) Ripple Rejection (1 kHz; Iout = 1.5 A) Thermal Shutdown Ground Current (Iout = 1.5 A) Output Noise Voltage (f = 100 Hz to 100 kHz, Iout = 1.5 A) Iq Vn Symbol Vout Vout Vout Vout Vout Vout Regline Regload Vdo Ilim RR RR Min 1.176 (−2%) 1.164 (−3%) 1.764 (−2%) 1.746 (−3%) 2.450 (−2%) 2.425 (−3%) − − − 1.6 − − − − − Typ 1.2 1.2 1.8 1.8 2.5 2.5 0.02 0.04 0.9 3.5 85 75 160 1.5 37 Max 1.224 (+2%) 1.236 (+3%) 1.836 (+2%) 1.854 (+3%) 2.550 (+2%) 2.575 (+3%) − − 1.3 − − − − 3.0 − Unit V V V V V V % % V A dB dB °C mA mVrms 4. Dropout voltage is a measurement of the minimum input/output differential at full load. http://onsemi.com 3 NCP566 TYPICAL CHARACTERISTICS 2.53 VOUT, OUTPUT VOLTAGE (V) 2.52 2.51 2.50 2.49 2.48 2.47 −50 −25 Vout = 2.5 V Iout = 10 mA 0 25 50 75 100 125 150 VOUT, OUTPUT VOLTAGE (V) 1.820 1.815 1.810 1.805 1.800 1.795 1.790 1.785 1.780 −50 −25 0 25 50 75 Vout = 1.8 V Iout = 10 mA 100 125 150 TJ, JUNCTION TEMPERATURE (°C) TJ, JUNCTION TEMPERATURE (°C) Figure 2. Output Voltage vs. Temperature 3.80 3.75 3.70 3.65 3.60 3.55 3.50 −50 Figure 3. Output Voltage vs. Temperature VOUT, OUTPUT VOLTAGE (V) 1.215 1.210 1.205 1.200 1.195 1.190 1.185 1.180 −50 −25 0 25 50 75 Vout = 1.2 V Iout = 10 mA 100 125 150 ISC, SHORT CIRCUIT CURRENT LIMIT (A) 1.220 −25 0 25 50 75 100 125 150 TJ, JUNCTION TEMPERATURE (°C) TJ, JUNCTION TEMPERATURE (°C) Figure 4. Output Voltage vs. Temperature 1.2 Vin − Vout, DROPOUT VOLTAGE (V) 1.0 Figure 5. Short Circuit Current Limit vs. Temperature Iout = 1.5 A 0.8 0.6 0.4 0.2 0 −50 Iout = 50 mA −25 0 25 50 75 100 125 150 TJ, JUNCTION TEMPERATURE (°C) Figure 6. Dropout Voltage vs. Temperature http://onsemi.com 4 NCP566 TYPICAL CHARACTERISTICS 1.70 IGND, GROUND CURRENT (mA) 1.65 1.60 1.55 1.50 1.45 Iout = 1.5 A 1.40 −50 −25 0 50 100 25 75 125 TJ, JUNCTION TEMPERATURE (°C) 150 IGND, GROUND CURRENT (mA) 1.80 1.75 1.70 1.65 1.60 1.55 0 300 600 900 1200 Iout, OUTPUT CURRENT (mA) 1500 Figure 7. Ground Current vs. Temperature Figure 8. Ground Current vs. Output Current 100 90 RIPPLE REJECTION (dB) 80 70 1000 Unstable 100 ESR (W) Iout = 1.5 A 10 Stable 1 100 1000 10000 F, FREQUENCY (Hz) 100000 1000000 0 250 500 750 1000 Vout = 2.5 V Cout = 10 mF 1250 1500 OUTPUT CURRENT (mA) 60 50 40 30 20 10 0 10 Figure 9. Ripple Rejection vs. Frequency Figure 10. Output Capacitor ESR Stability vs. Output Current Vout = 1.2 V Vout = 1.2 V Figure 11. Load Transient from 10 mA to 1.5 A Figure 12. Load Transient from 10 mA to 1.5 A http://onsemi.com 5 NCP566 TYPICAL CHARACTERISTICS Vout = 1.2 V Vout = 1.2 V Figure 13. Load Transient from 1.5 A to 10 mA 140 120 NOISE DENSITY (nV/√Hz) 100 80 60 40 20 0 0 10 20 30 40 50 60 70 80 90 100 f, FREQUENCY (kHz) Vout = 1.2 V Iout = 10 mA NOISE DENSITY (nV/√Hz) 140 120 100 80 60 40 20 0 0 Figure 14. Load Transient from 1.5 A to 10 mA Vout = 1.2 V Iout = 1.5 A 10 20 30 40 50 60 70 80 90 100 f, FREQUENCY (kHz) Figure 15. Noise Density vs. Frequency Figure 16. Noise Density vs. Frequency http://onsemi.com 6 NCP566 APPLICATION INFORMATION The NCP566 low dropout linear regulator provides fixed voltages at currents up to 1.5 A. It features ultra fast transient response and low dropout voltage. These devices contain output current limiting, short circuit protection and thermal shutdown protection. Input, Output Capacitor and Stability for use with a 150 mF OSCON 16SA150M type in parallel with a 10 mF OSCON 10SL10M type from Sanyo. The 10 mF capacitor is used for best AC stability while 150 mF capacitor is used for achieving excellent output transient response. The output capacitors should be placed as close as possible to the output pin of the device. If not, the excellent load transient response of NCP566 will be degraded. Load Transient Measurement An input bypass capacitor is recommended to improve transient response or if the regulator is located more than a few inches from the power source. This will reduce the circuit’s sensitivity to the input line impedance at high frequencies and significantly enhance the output transient response. Different types and different sizes of input capacitors can be chosen dependent on the quality of power supply. A 150 mF OSCON 16SA150M type from Sanyo should be adequate for most applications. The bypass capacitor should be mounted with shortest possible lead or track length directly across the regulator’s input terminals. The output capacitor is required for stability. The NCP566 remains stable with ceramic, tantalum, and aluminum− electrolytic capacitors with a minimum value of 1.0 mF with ESR between 50 mW and 2.5 W. The NCP566 is optimized GEN Large load current changes are always presented in microprocessor applications. Therefore good load transient performance is required for the power stage. NCP566 has the feature of ultra fast transient response. Its load transient responses in Figures 11 through 14 are tested on evaluation board shown in Figure 17. The evaluation board consists of NCP566 regulator circuit with decoupling and filter capacitors and the pulse controlled current sink to obtain load current transitions. The load current transitions are measured by current probe. Because the signal from current probe has some time delay, it causes un−synchronization between the load current transition and output voltage response, which is shown in Figures 11 through 14. Vout −VCC Vin Pulse + NCP566 Evaluation Board GND V RL + GND Scope Voltage Probe Figure 17. Schematic for Transient Response Measurement http://onsemi.com 7 NCP566 PCB Layout Considerations Thermal Considerations Good PCB layout plays an important role in achieving good load transient performance. Because it is very sensitive to its PCB layout, particular care has to be taken when tackling Printed Circuit Boa