300mA Linear Voltage Regulator

www.DataSheet4U.com LP3991 300mA Linear Voltage Regulator for Digital Applications January 2007 LP3991 300mA Linear Voltage Regulator for Digital Applications General Description Operating from a minimum input voltage of 1.65V, the LP3991 regulator has been designed to provide fixed stable output voltages for load currents up to 300mA. This device is suitable where accurate, low voltages are required from low input voltage sources and is therefore suitable for post regulation of switched mode regulators. In such applications, significant improvements in performance and EMI can be realized, with little reduction in overall efficiency. The LP3991 will provide fixed outputs as low as 1.2V from a wide input range of 1.65V to 3.6V Using the enable pin, the device may be controlled to provide a shutdown state, in which negligible supply current is drawn. The LP3991 is designed to be stable with space saving ceramic capacitors as small as 0402 case size. Performance is specified for a -40°C to 125°C junction temperature range. For output voltage options please contact your local NSC sales office. Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Operation from 1.65V to 3.6V Input 1% accuracy at room temperature Output Voltage from 1.2V to 2.8V 125mV Dropout at 300mA load 50µA Quiescent Current at 1mA Load Inrush Current controlled to 600mA PSRR 65dB at 1kHz 100µs Start-Up time for 1.5V VOUT Stable with Ceramic Capacitors as small as 0402 Thermal-Overload and Short-Circuit Protection Package 4 pin micro SMD (0.963mm x 1.446mm) For other package options contact your NSC sales office. Applications ■ Post DC/DC Regulator ■ Battery Operated Devices ■ Hand-Held Information Appliances Typical Application Circuit 20110002 © 2007 National Semiconductor Corporation 201100 www.national.com LP3991 Pin Descriptions Packages Pin No. B1 Symbol VOUT Name and Function Voltage output. A Low ESR Ceramic Capacitor should be connected from this pin to GND. (See Application Information) Connect this output to the load circuit. Common Ground. Connect to Pad. Disables the Regulator when ≤ 0.4V. Enable Input has an internal 1.2MΩ pull-down resistor to GND. B2 VIN Voltage Supply Input. A 1.0µF capacitor should be connected from this pin to GND. Enable Input; Enables the Regulator when ≥ 0.95V. A1 A2 GND VEN Connection Diagram 4 Bump Thin Micro SMD, Large Bump 20110006 See NS package number TLA04 www.national.com 2 LP3991 Ordering Information (4-Bump Micro SMD) * Please contact Sales Office for Availability Only available in Lead Free option. Output Voltage (V) 1.2 1.3 1.5 1.8* 2.0* 2.5* 2.8 Grade STD STD STD STD STD STD STD LP3991 Supplied as 1000 Units, Tape and Reel LP3991TL-1.2 LP3991TL-1.3 LP3991TL-1.5 LP3991TL-1.8 LP3991TL-2.0 LP3991TL-2.5 LP3991TL-2.8 LP3991 Supplied as 3000 Units, Tape and Reel LP3991TLX-1.2 LP3991TLX-1.3 LP3991TLX-1.5 LP3991TLX-1.8 LP3991TLX-2.0 LP3991TLX-2.5 LP3991TLX-2.8 3 www.national.com LP3991 Absolute Maximum Ratings (Notes 1, 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN, VOUT, Pins: Voltage to GND -0.3 to 6.5V VEN Pin: Voltage to GND -0.3 to (VIN + 0.3V) to 6.5V (max) Junction Temperature 150°C Lead/Pad Temp. (Note 3) Micro SMD 260°C Storage Temperature -65 to 150°C Continuous Power Dissipation Internally Limited (Note 4) ESD (Note 5) Human Body Model 2KV Machine Model 200V Operating Ratings (Note 1) 1.65 to 3.6V 300mA -40°C to 125°C -40°C to 85°C Input Voltage Range Recommended Load Current Junction Temperature Ambient Temperature TARange (Note 6) Thermal Properties Junction To Ambient Thermal Resistance(Note 7) θJA JEDEC Board (Note 8) θJA 4 Layer Board (Note 1) 88°C/W 160°C/W Electrical Characteristics Unless otherwise noted, VEN =950mV, VIN = VOUT + 0.5V, or 1.8V, whichever is higher. CIN = 1µF, IOUT = 1.0mA, COUT =4.7µF. Typical values and limits appearing in normal type apply for TA = 25°C. Limits appearing in boldface type apply over the full junction temperature range for operation, −40 to +125°C. (Note 9) Symbol VIN ΔVOUT Parameter Input Voltage Output Voltage Tolerance (Note 10) VIN = VIN(NOM) to 3.6V ILOAD = 1 to Temperature (TJ)= 300mA -25°C to +85°C VIN = VOUT(NOM) +0.5V to 3.6V, IOUT = 1mA IOUT = 1mA to 300mA VOUT = 1.8V VOUT = 2.8V ILOAD IQ Minimum Load Current Quiescent Current (Note 12) VEN = 950mV, IOUT = 0mA VEN = 950mV, IOUT = 300mA VEN = 0.4V ISC IOUT PSRR Short Circuit Current Limit Maximum Output Current Power Supply Rejection Ratio (Note 14) Output noise Voltage (Note 14) Thermal Shutdown f = 1kHz, IOUT = 1mA to 300mA BW = 10Hz to 100kHz, VIN = 4.2V, COUT = 4.7µF Temperature Hysteresis 65 VIN = 3.6V (Note 13) 50 120 0.001 550 300 IOUT = 150mA IOUT = 300mA IOUT = 150mA IOUT = 300mA 0.05 10 65 125 40 75 0 100 225 1.0 900 mA mA dB µVRMS °C µA Conditions Typ Limit Min 1.65 -1.0 -3.0 -2.5 Max 3.6 1.0 3.0 2.5 Units V % Line Regulation Error Load Regulation Error VDO Dropout Voltage(Note 11) 1 60 90 180 80 160 %/V µV/mA mV mA en TSHUTDOWN 280 160 20 www.national.com 4 LP3991 Electrical Characteristics con't. Unless otherwise noted, VEN =950mV, VIN = VOUT + 0.5V, or 1.8V, whichever is higher. CIN = 1µF, IOUT = 1.0mA, COUT =4.7µF. Typical values and limits appearing in normal type apply for TA = 25°C. Limits appearing in boldface type apply over the full junction temperature range for operation, −40 to +125°C. (Note 9) Symbol Parameter Conditions Typ Limit Min Max Units Enable Control Characteristics IEN (Note 15) VIL VIH TON Maximum Input Current at VEN Input Low Input Threshold High Input Threshold Turn On Time (Note 14) VEN = 0V, VIN = 3.6V VEN = VIN = 3.6V VIN = 1.65V to 3.6V VIN = 1.65V to 3.6V To 95% Level VIN(MIN) to 3.6V VOUT ≤ 2.0V VOUT > 2.0V 100 140 6 140 110 80 110 80 60 100 70 50 0 600 2 1000 % mA mV 0.95 0.001 3 5.5 0.4 µA V V Timing Characteristics µs mV (pk - pk) Line Transient Response |δVOUT| Trise = Tfall = 30µs (Note 14) δVIN = 600mV Transient Response Load Transient Response |δVOUT| Trise = Tfall = 1µs IOUT = 0 mA to 300mA (Note 14) IOUT = 1mA to 300mA IOUT = 300mA to 1mA IOUT = 0mA to 200mA IOUT = 1mA to 200mA IOUT = 200mA to 1mA IOUT = 0mA to 150mA IOUT = 1mA to 150mA IOUT = 150mA to 1mA Overshoot on Start-up IIR In-Rush Current (Note 14) Note 1: Absolute Maximum Ratings are limits beyond which damage can occur. Operating Ratings are conditions under which operation of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical Characteristics tables. Note 2: All Voltages are with respect to the potential at the GND pin. Note 3: For further information on these packages please refer to the following application notes,AN-1112 Micro SMD Wafer Level Chip Scale Package. Note 4: Internal thermal shutdown circuitry protects the device from permanent damage. Note 5: The human body model is 100pF discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged directly into each pin. Note 6: The maximum ambient temperature (TA(max)) is dependant on the maximum operating junction temperature (TJ(max-op) = 125°C), the maximum power dissipation of the device in the application (PD(max)), and the junction to ambient thermal resistance of the part / package in the application (θJA), as given by the following equation: TA(max) = TJ(max-op) - (θJA × PD(max)). Note 7: Junction to ambient thermal resistance is dependant on the application and board layout. In applications where high maximum power dissipation is possible, special care must be paid to thermal dissipation issues in board design. Note 8: Full details can be found in JESD61-7 Note 9: All limits are guaranteed. All electrical characteristics having room-temperature limits are tested during production at TJ = 25°C or correlated using Statistical Quality Control methods. Operation over the temperature specification is guaranteed by correlating the electrical characteristics to process and temperature variations and applying statistical process control. Note 10: VIN(MIN) = VOUT(NOM) + 0.5V or 1.65V, whichever is greater. (See post DC/DC convertor example in application information section). Note 11: Dropout voltage is voltage difference between input and output at which the output voltage drops to 100mV below its nominal value. This parameter is only specified for output voltages above 1.8V. Note 12: The device maintains the regulated output voltage without a load. Note 13: Short circuit current is measured with VOUT pulled to 0V. Note 14: This electrical specification is guaranteed by design. Note 15: Enable Pin has an internal 1.2MΩ typical, resistor connected to GND. 5 www.national.com LP3991 Output Capacitor, Recommended Specifications Parameter COUT Output Capacitor Capacitance (Note 16) Conditions VOUT ≥ 1.5V VOUT < 1.5V (Note 17) Typ 4.7 2.2 Limit Min 2 1.6 5 500 µF mΩ Max Units ESR Note 16: The capacitor tolerance should be 30% or better over temperature. The full operating conditions for the application should be considered when selecting a suitable capacitor to ensure that the minimum value of capacitance is always met. Recommended capacitor type is X7R or X5R. (See capacitor section in Applications Hints) Note 17: On lower voltage options, 2.2µF output capacitor may be used but some degradation in load transient (10 -15%) can be expected, compared to a 4.7µF. www.national.com 6 LP3991 Typical Performance Characteristics. Output Voltage Change vs Temperature Unless otherwise specified, CIN = 1.0µF Ceramic, COUT = 4.7µF Ceramic, VIN = VOUT(NOM) + 0.5V or 1.8V whichever is greater, TA = 25°C, VOUT(NOM) = 1.5V , Shutdown pin is tied to VIN. Output Voltage vs Minimum Input Voltage 20110010 20110009 Ground Current vs Load Cu