LSP2133 250/W - Datasheet Archive

 

LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator FEATURES GENERAL DESCRIPTION Low dropout voltage: 180mV at 300mA

 

Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator FEATURES GENERAL DESCRIPTION Low dropout voltage: 180mV at 300mA (Vo=3.3V) Quiescent current: Typ. 65µA ±2% Voltage Accuracy High PSRR: 67dB at 100Hz Thermal Shutdown Current Limiting Excellent line and load regulation Fast response Short circuit protection Low temperature coefficient Shutdown current: 0.5µA Space saving SOT23-5L package The LSP2133 LSP2133 is a positive adjustable voltage linear regulator features low quiescent current (Typ. 65µA) and low dropout voltage, making it ideal for battery powered applications. Their high PSRR make them useful in applications where AC noise on the input power supply must be suppressed. Space saving SOT23-5L package is attractive for portable and handheld applications. They have both thermal shutdown and a current limit feature to prevent device failure from extreme operating conditions. They are stable with an output capacitor of 2.2µF or greater. APPLICATIONS Cordless phones Cellular phones Bluetooth earphones Digital Cameras Portable electronics WLANs MP3 players PIN CONFIGURATION (Top View) 1 5 2 3 4 PIN DESCRIPTION Pin Number Pin Name 1 2 3 4 5 Pin Function VIN GND EN ADJ VOUT Input Ground Chip Enable (active high) Adjustable pin Output BLOCK DIAGRAM 1/8 Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator TYPICAL APPLICATIONS CIRCUITS ABSOLUTE MAXIMUM RATINGS Parameter Input Supply Voltage Output Current Rating +6 300 Unit V mA Output Pin Voltage GND-0.3 to VIN+0.3 V Internal Power Dissipation 400 mW Junction to Case Thermal Resistance (JC) 130 / W Junction to Ambient Thermal Resistance (JA) 250 / W Operating temperature -40 to 85 °C Operating Junction Temperature -40 to 125 °C Storage Temperature -65 to 150 °C Lead Temperature (Soldering, 5 sec) 300 Note: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. 2/8 °C Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator ELECTRICAL CHARACTERISTICS (VIN = 4V, VO = 3V, CIN = 1µF, CO = 2.2µF, TA= 25°C unless otherwise specified.) PARAMETER SYMBOL Input Voltage Output Voltage Reference Voltage Output Voltage Accuracy Output Current Short Circuit Current Ground Current Quiescent Current Line Regulation Load Regulation Error Temperature Coefficient Over Temperature Shutdown Over Temperature Hystersis VIN VO VREF VO IO ISC IGND IQ LNR LDR TC OTS OTH Power Supply Ripple Rejection PSRR Dropout Voltage VDO EN Input High Threshold EN Input Low Threshold VIH VIL Output Noise Vn TEST CONDITIONS MIN TYP UNIT 5.5 5 Note1 1.2 MAX V V V % mA mA 1.235 IO= 1mA VO = 0V IO= 1mA to 300mA IO= 0mA IO= 1mA, VIN =3V to 5V IO = 1mA to 300mA IO = 1mA IO = 1mA IO = 1mA f=100Hz IO = 100mA f= 1KHz Vo =1.2V f= 10KHz IO = 300mA -2 300 -0.4 -1 f = 10Hz to 100kHz 150 70 65 0.2 0.2 40 150 30 67 65 90 90 0.4 1 µA µA %/V % ppm/°C °C °C dB 42 2.5 VO < 3.3V VO 3.3V VIN = 2.5V to 5V VIN = 2.5V to 5V +2 Note2 370 450 180 230 1.5 0.3 50 mV V V µVRMS Shutdown Current ISD VEN = 0V 0.01 1 µA Note 1The minimum input voltage of the LSP2133 LSP2133 is determined by output voltage and dropout voltage. The minimum input voltage is defined as: VIN(MIN)=VO+VDROP Note 2Output current is limited by PD, maximum IO=PD/(VIN(MAX)-VO) 3/8 Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator APPLICATION INFORMATION Capacitor Selection and Regulator Stability Similar to any low dropout regulator, the external capacitors used with the LSP2133 LSP2133 must be carefully selected for regulator stability and performance. Using a capacitor, CIN, whose value is1uF at the LSP2133 LSP2133 input pin, the amount of the capacitance can be increased without limit. Please note that the distance between CIN and the input pin of the LSP2133 LSP2133 should not exceed 0.5 inch. Ceramic capacitors are suitable for the LSP2133 LSP2133. Capacitors with larger values and lower ESR provide better PSRR and line-transient response. The LSP2133 LSP2133 is designed specifically to work with low ESR ceramic output capacitors in order to save space and improve performance. Using an output ceramic capacitor whose value is 2.2F with ESR5m ensure stability. ADJ Output Voltage Programming The output voltage of the LSP2133 LSP2133 adjustable regulator is programmed by using an external resistor divider as shown in figure 1. The output voltage is calculated using: Resistor R1 and R2 should be chosen for approximately 7uA divider current. Low value resistors can be used but offer no advantage and waste more power. Higher value should be avoided as leakage current at ADJ pin increase the output voltage error. Cc is unnecessary when R1 or R2 20K. The recommended design procedure is to choose R2=169k to set the divider current at 7uA and then calculated R1 using: Load Transient Considerations The figure7 shows the LSP2133 LSP2133 load transient response. It shows two components the output response: a DC shift from the output impedance due to the load current change and transient response. The DC shift is quite small due to excellent load regulation of the LSP2133 LSP2133. The transient spike, resulting from a step change in the load current from 1mA to 300mA, is 20mV. The ESR of the output capacitor is critical to the transient spike. A larger capacitance along with smaller ESR results in a smaller spike. Shutdown Input Operation The LSP2133 LSP2133 is shutdown by pulling the EN input low, and is turned on by tying the EN input to VIN or leaving the EN input floating. Internal P-Channel Pass Transistor The LSP2133 LSP2133 features a 0.75 P-Channel MOSFET device as a pass transistor. The P-MOS pass transistor enables the LSP2133 LSP2133 to consume only 65A of ground current during low dropout, light load, or heavy load operations. This feature increases the battery operation life time. Dropout Voltage A regulator's minimum dropout voltage determines the lowest usable supply voltage. The LSP2133 LSP2133 has a typical 300mV dropout voltage. In battery powered systems, this will determine the useful end-of-life battery voltage. Current Limit and Short Circuit Protection The LSP2133 LSP2133 features a current limit, which monitors and controls the gate voltage of the pass transistor. The output current can be limited to 400mA by regulating the gate voltage. The LSP2133 LSP2133 also has a built-in short circuit current limit. Thermal Considerations Thermal protection limits power dissipation in the LSP2133 LSP2133. When the junction temperature exceeds 150, the OTP (Over Temperature Protection) starts the thermal shutdown and turns the pass transistor off. The pass transistor resumes operation after the junction temperature drops below 120. For continuous operation, the junction temperature should be maintained below 125. The power dissipation is defined as : PD=(VIN-VOUT)*IO+VIN*IGND The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surrounding airflow and temperature difference between junction and ambient. The maximum power dissipation can be calculated by the following formula: PD(MAX)=(TJ(MAX)-TA)/JA Where TJ(MAX) is the maximum allowable junction temperature 125. TA is the ambient temperature and JA is the thermal resistance from the junction to the ambient. For example, JA is 250/W 250/W for the SOT23-5L package, based on the standard JEDEC 51-3 for a single layer thermal test board. The maximum power dissipation at TA=25 can be calculated by the following formula: PD(MAX)= (125-25)/250=0.4W 4/8 Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator It is also useful to calculated the junction temperature of the LSP2133 LSP2133 under a set of specific conditions. In this example let the input voltage VIN=3.3V, the output current IO=300mA and the case temperature TA=40 measured by a thermal couple during operation. The power dissipation for the VO=2.8V version of the LSP2133 LSP2133 can be calculated as: PD=(3.3V-2.8V)*300mA+3.3V*70A 150mW And the junction temperature, TJ, can be calculated as follows: TJ=TA+PD*JA TJ=40+0.15W*250/W 250/W =77.5TJ(MAX) =125 For this operating condition, TJ, is lower than the absolute maximum operating junction temperature, 125, so it is safe to use the LSP2133 LSP2133 in this configuration. TYPICAL PERFORMANCE CHARACTERISTICS (V0 = 1.2V, CIN = 1µF, CO = 2.2µF , TA = 25°C unless otherwise specified.) 5/8 Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator TYPICAL PERFORMANCE CHARACTERISTICSCONTINUED (V0 = 1.2V, CIN = 1µF, CO = 2.2µF , TA = 25°C unless otherwise specified.) 6/8 Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator TYPICAL PERFORMANCE CHARACTERISTICSCONTINUED (V0 = 1.2V, CIN = 1µF, CO = 2.2µF , TA = 25°C unless otherwise specified.) ORDERING INFORMATION MARKING INFORMATION SOT23-5L 7/8 Rev1.2 Liteon Semiconductor Corporation LSP2133 LSP2133 300mA High PSRR Low Dropout CMOS Linear Regulator PACKAGE INFORMATION SEATING PLANE D b L E L1 E1 c e L2 e1 M1 A A2 M2 A1 Symbol A A1 A2 b c D E E1 e e1 L L1 L2 M1 M2 GAUGE PLANE Min Dimensions In Millimeters Typ 1.05 0.05 1.00 0.30 0.08 2.80 2.60 1.50 1.20 0.10 1.10 2.90 2.80 1.60 0.95 BSC 1.90 BSC 0.45 0.60 REF 0.25 BSC 5° 8° 0.30 3° 6° 8/8 Max 1.35 0.15 1.20 0.50 0.22 3.00 3.00 1.70 0.55 7° 10° Rev1.2