500 mA / Low-Noise LDO Voltage Regulator

® SPX3819 500mA, Low-Noise LDO Voltage Regulator FEATURES ■ ■ ■ ■ ■ ■ ■ Low Noise: 40µV Possible High Accuracy: 1% Reverse Battery Protection Low Dropout: 340mV at Full Load Low Quiescent Current: 90µA Zero Off-Mode Current Fixed Output: 1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.1V, 3.3V, 5.0V ■ 5 Pin SOT-23, 8 Pin nSOIC and 8 pin 2X3 DFN Packages. Battery Powered Systems Cordless Phones Radio Control Systems Portable/Palm Top/Notebook Computers Portable Consumer Equipment Portable Instrumentation Bar Code Scanners SMPS Post Regulators EN NC VIN 1 2 3 4 8 ADJ/BYP GND NC VOUT SPX3819 7 8 Pin DFN 6 5 NC APPLICATIONS ■ ■ ■ ■ ■ ■ ■ ■ Now Available in Lead Free Packaging DESCRIPTION The SPX3819 is a positive voltage regulator with a low dropout voltage and low noise output. In addition, this device offers a very low ground current of 800µA at 100mA output. The SPX3819 has an initial tolerance of less than 1% max and a logic compatible ON/OFF switched input. When disabled power consumption drop to nearly zero. Other key features include reverse battery protection, current limit, and thermal shutdown. The SPX3819 includes a reference bypass pin for optimal low noise output performance. With its very low output temperature coefficient, this device also makes a superior low power voltage reference. The SPX3819 is an excellent choice for use in battery-powered applications such as cordless telephones, radio control systems, and portable computers. It is available in several fixed voltages 1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.1V, 3.3V, 5.0V or with an adjustable output. This device is offered in 8 pin nSOIC, 8 pin DFN and 5-pin SOT-23 packages. TYPICAL APPLICATION CIRCUIT VIN 1 5 VOUT + 2 + GND 3 EN ENABLE may be tied directly to VIN SPX3819 4 BYP (Opt.) TOP View Date:6/8/2004 SPX3819 500mA, Low Noise LDO Voltage Regulator © Copyright 2004 Sipex Corporation 1 ABSOLUTE MAXIMUM RATINGS Power Dissipation ...................................................... Internally Limited Lead Temp. (Soldering, 5 Seconds) ........................................... 260°C Operating Junction Temperature Range ................... -40°C to +125°C Input Supply Voltage ........................................................ -20V to +20V Enable Input Voltage ........................................................ -20V to +20V RECOMMENDED OPERATIONG CONDITIONS Input Voltage ................................................................... +2.5V to+16V Operating Junction Temperature Range ................... -40°C to +125°C Enable Input Voltage .............................................................. 0V to VIN ELECTRICAL CHARACTERISTICS TJ=25°C, VOUT + 1V, for 1.2V Option VIN=VOUT + 1.2V IL=100µA, CL=1µF, and VENABLE ≥ 2.4V. The ♦ denotes the specifications which apply over full operating temperature range -40°C to +85°C, unless otherwise specified. PARAMETER Output Voltage Tolerance Output Voltage Temperature Coef. Line Regulation Load Regulation Dropout Voltage (VIN-VO)(Note 2) MIN -1 -2 57 0.04 0.05 10 125 180 340 Quiescent Current (IGND) Ground Pin Current (IGND) 0.05 90 250 1.0 6.5 Ripple Rejection (PSRR) Current Limit (ILIMIT) Output Noise (eNO) 70 800 950 300 40 Input Voltage Level Logic Low (VIL) Input Voltage Level Logic High (VIH) ENABLE Input Current Thermal Resistance (Note 1) 2 0.01 3 220 180 2 20 0.4 µVRMS µVRMS V V µA °C/W °C/W ♦ ♦ 0.1 0.4 60 80 175 250 350 450 550 700 3 8 150 190 650 900 2.0 2.5 25.0 30.0 TYP MAX +1 +2 UNITS % ♦ ppm/°C %/V % mV ♦ mV ♦ mV ♦ mV ♦ µA ♦ µA ♦ µA ♦ mA ♦ mA ♦ dB mA ♦ IL=10mA, CL=1.0µF, CIN=1µF, (10Hz-100kHz) IL=10mA, CL=10µF, CBYP =1µF, CIN =1µF, (10Hz-100kHz) OFF ON VIL ≤ 0.4V VIH ≥ 2.0V SOT-23-5 / Junction to Ambient SO-8 / Junction to Ambient VOUT = 0V IL = 500mA IL = 150mA IL = 50mA VENABLE ≤ 0.4V VENABLE ≤ 0.25V IL = 100µA IL = 500mA IL = 150mA IL = 50mA VIN=VOUT + 1V to 16V IL = 0.1mA to 500mA IL = 100µA ♦ CONDITIONS NOTES Note 1: The maximum allowable power dissipation is a function of maximum operating junction temperature, TJ(max) the junction to ambient thermal resistance, and the ambient θJA, and the ambient temperature TA. The maximum allowable power dissipation at any ambient temperature is given: PD(max) = (TJ(max)-TA)/θJA, exceeding the maximum allowable power limit will result in excessive die temperature; thus, the regulator will go into thermal shutdown. The θJA of the SPX3819 is 220°C/W mounted on a PC board. Note 2: Not applicable to output voltage 2V or less. Date:6/8/2004 SPX3819 500mA, Low Noise LDO Voltage Regulator © Copyright 2004 Sipex Corporation 2 TYPICAL PERFORMANCE CHARACTERISTICS 7.0 3.3V Device VIN= 4.3V CL = 1.0µF 160 150 140 130 6.0 5.0 IGND (mA) IGND (µA) 4.0 120 110 100 90 80 3.3V Device CL= 1.0µF IL = 100µA 3.0 2.0 1.0 70 0.0 0 100 200 300 400 500 60 4 6 8 10 12 14 16 IL (mA) VIN (V) Ground Current vs Load Current Ground Current vs Input Voltage 14.0 3.3V Device VIN= 4.3V CL = 1.0µF 3.350 3.345 3.340 3.335 3.330 12.0 10.0 IGND (mA) VOUT (V) 8.0 3.325 3.320 3.315 3.310 3.3V Device CL= 1.0µF IL = 100µA 6.0 4.0 3.305 3.300 2.0 3.295 3.290 0.0 0 100 200 300 400 500 4 6 8 10 12 14 16 IL (mA) VIN (V) Ground Current vs Load Current in Dropout Output Voltage vs Input Voltage Date:6/8/2004 SPX3819 500mA, Low Noise LDO Voltage Regulator © Copyright 2004 Sipex Corporation 3 TYPICAL PERFORMANCE CHARACTERISTICS: Continued 350 300 3.3V Device VIN= 3.2V CL = 1.0µF 3.316 3.314 3.312 3.310 Dropout (mV) 250 200 3.3V Device VIN= 4.3V CL = 1.0µF VOUT (V) 3.308 3.306 3.304 150 100 50 3.302 0 0 100 200 300 400 500 3.300 0 100 200 300 400 500 IL (mA) Dropout Voltage vs Load Current IL (mA) Output Voltage vs Load Current 130 3.3V Device VIN= 4.3µF CL= 1.0µF IL = 100µA 360 3.3V Device VIN = 4.3 CL= 1.0µF IL = 50mA 120 340 320 110 IGND (µA) 300 100 IGND (µA) 280 260 90 240 80 220 70 -40 -20 0 20 40 60 80 100 120 200 -40 -20 0 20 40 60 80 100 120 Temperature (°C) Temperature (°C) Ground Current vs Temperature with 100µA Load Ground Current vs Temperature with 50mA Load Date:6/8/2004 SPX3819 500mA, Low Noise LDO Voltage Regulator © Copyright 2004 Sipex Corporation 4 TYPICAL PERFORMANCE CHARACTERISTICS: Continued 8.0 14.0 3.3V Device VIN= 4.3µF CL= 1.0µF IL = 500mA 7.5 3.3V Device VIN= 4.3µF CL= 1.0µF IL = 500mA 13.5 13.0 IGND (mA) -40 -20 0 20 40 60 80 100 120 IGND (mA) 12.5 7.0 12.0 11.5 6.5 11.0 6.0 10.5 -40 -20 0 20 40 60 80 100 120 Temperature (°C) Temperature (°C) Ground Current vs Temperature with 500mA Load Ground Current vs Temperature in Dropout 1.30 3.3V Device CL= 1.0µF IL = 100µA 3.400 3.380 3.360 3.340 3.3V Device VIN= 4.3µF CL= 1.0µF IL = 500mA 1.25 VEN, On Threshold (V) 1.20 VOUT (V) 3.320 3.300 2.280 1.15 1.10 2.260 2.240 1.05 2.220 1.00 4 6 8 10 12 14 16 2.200 -40 -20 0 20 40 60 80 100 120 VIN (V) Temperature (°C) ENABLE Voltage, ON threshold, vs Input Voltage Output Voltage vs Temperature Date:6/8/2004 SPX3819 500mA, Low Noise LDO Voltage Regulator © Copyright 2004 Sipex Corporation 5 TYPICAL PERFORMANCE CHARACTERISTICS: Continued 350 Cin = 1uFT, Cout = 1uFT Cin = 1uFT, Cout = 2.2uFT Cin = 1uFT Cout = 10uFT 300 250 200 uV RMS 150 100 50 0 1 10 100 1000 10000 Bypass Cap (pF) 100000 1000000 Output Noise vs Bypass Capacitor Value IL = 10mA, 10Hz - 100kHz Line Transient Response for 3.3V Device Load Transient Response for 3.3V Device Date:6/8/2004 SPX3819 500mA, Low Noise LDO Voltage Regulator © Copyright 2004 Sipex Corporation 6 APPLICATION INFORMATION The SPX3819 requires an output capacitor for device stability. Its value depends upon the application circuit. In general, linear regulator stability decreases with higher output currents. In applications where the SPX3819 is putting out less current, a lower output capacitance may be sufficient. For example, a regulator sourcing only 10mA, requires approximately half the capacitance as the same regulator sourcing 150mA. Bench testing is the best method for determining the proper type and value of the capacitor since the high frequency characteristics of electrolytic capacitors vary widely, depending on type and manufacturer. A high quality 2.2µF aluminum electrolytic capacitor works in most application circuits, but the same stability often can be obtained with a 1µF tantalum electrolytic. With the SPX3819 adjustable version, the minimum value of output capacitance is a function of the output voltage. The value decreases with higher output voltages, since closed loop gain is increased. Typical Applications Circuits The SPX3819 start-up speed is inversely proportional to the size of the BYP capacitor. Applications requiring a slow ramp-up of the output voltage should use a larger CBYP. However, if a rapid turn-on is necessary, the BYP capacitor can be omitted. The SPX3819’s internal reference is available through the BYP pin. Figure 1 represents a SPX3819 standard application circuit. The EN (enable) pin is pulled high (>2.0V) to enable the regulator. To disable the regulator, EN < 0.4V. The SPX3819 in Figure 2 illustrates a typical adjustable output voltage configuration. Two resistors (R1 and R2) set the output voltage. The output voltage is calculated using the formula: VOUT = 1.235V x [ 1 + R1/R2] R2 must be > 10 kΩ and for best results, R2 should be between 22 kΩ and 47kΩ. A capacitor placed between Adj and ground will provide improved noise performance. A 10nF capacitor on BYP pin will significantly reduce output noise but it may be left unconnected if the output noise is not a major concern. VIN 1 5 VOUT VIN 1 5 VOUT + 2 + GND 3 EN ENABLE may be tied directly to VIN SPX3819 + GND 2 SPX3819 SOT-23 3 4 ADJ R1 + 4 BYP (Opt.) EN Hi-ON Lo-OFF BYP (Opt.) R2 TOP View TOP View Figure 1. Standard App