id id mA, Low Dropout, Low Noise Ultra-Fast With Soft Start CMOS LDO Regulator Features General Description Applications

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1 500mA, Low Dropout, Low Noise Ultra-Fast With Soft Start CMOS LDO Regulator General Description The is a 500mA, low dropout and low noise linear regulator with high ripple rejection ratio. It has fixed output voltage ranging from 1.8V to 3.3V. The includes a reference voltage source, an error amplifier, driver transistors and an internal current limiter. It also incorporates current fold-back to reduce power dissipation when the output is short circuited. The works well with low ESR ceramic capacitors, suitable for portable RF and wireless battery-powered applications with stringent space requirements and demanding performance. It also offers ultra low noise output and has low quiescent current. Ordering Information - Features Ultra-Low-Noise Application Wide 2.5V to 6V Operating Range Stable with Low-ESR Output Capacitor. Six Fixed Voltage Options Available Internal Current Limiter Short Circuit Current Fold-back Thermal Shutdown Protection Low Dropout : 500mA High Ripple Rejection 70dB@1kHz Standby Current Less Than 0.1μA Auto Discharge Applications Battery-Powered Equipment Portable Instruments Digital Camera WLAN Communication Hand-Held Instruments Packing Package R: Tape and Reel C50:SC-70-5 A50:SOT-23-5 B50:TSOT-23-5 I23:TO-252-2L Output Voltage Voltage Code Marking Information For marking information, please contact our sales representative directly or through distributor around your location. Other voltage outputs may be available. For further details, please contact an idesyn sales or distributor. Jan Rev 1.1

2 Typical Application Circuit V IN C IN 1µF/ X7R V IN V OUT C OUT 1µF/ X7R V OUT Enable 100K EN SS GND C SS 0.5nF/ X7R Absolute Maximum Ratings (Note 1) Recommended Operating Conditions Supply Voltage V IN 6V Input Voltage V IN 2.5V to 6V Power Dissipation, P T A =25 C EN Input Voltage 0V to 6V SC mW Junction Temperature -40 C to 125 C (T)SOT mW Ambient Operating Temperature 40 C to 85 C TO-252-2L 1200mW Thermal Resistance, JA SC C/W (T)SOT C/W TO-252-2L 83.3 C/W Lead Temperature 260 C Storage Temperature -65 C to 150 C ESD Susceptibility HBM (Human Body Mode) MM (Machine Mode) 4kV 300V Jan Rev 1.1

3 Electrical Characteristics (Unless otherwise specified V IN = V OUT + 1V, T A =25 C) Parameters Symbol Condition Min Typ Max Units Operating Voltage Range (Note 2) V IN 6 V Standby Current I SBY V EN = GND,Shutdown μa Quiescent Current I Q 90 μa Supply Current Limit (Note 3) I LIMIT V OUT > 200mV ma Short Circuit Current I SC V OUT < 200mV ma V OUT = 1.8V mv V OUT = 2.5V mv V OUT = 2.7V mv Dropout Voltage (Note 4) V DROP I OUT = 500mA V OUT = 2.8V mv V OUT = 3.0V mv V OUT = 3.1V mv V OUT = 3.3V mv EN input Bias Current I IBSD V EN = GND or V IN na Line Regulation ΔV LINE V IN = (V OUT +1V) to 5.5V, I OUT = 1mA 10 mv/v Load Regulation ΔV LOAD 1mA < I OUT < 500mA mv Output Noise Voltage eno 10Hz to 100KHz I OUT = 200mA C OUT = 1μF 100 μv RMS Thermal Shutdown Temperature T SD 165 C Thermal Shutdown Temperature Hysteresis ΔT SD 30 C Output Voltage Accuracy ΔV OUT I OUT = 1mA % C IN = 1μF, C OUT = 1μF, C ss = Soft Start Time T SS NC, V OUT =3.3V, I OUT = 0mA, 9 μs T SS =0 to V OUT 90% Fast Discharge N-MOSFET Turn On Resistance R DISCHARGE V IN = 4V, V EN = 0V 35 Ω EN Threshold Logic-Low V V IL V IN = 3V to 5.5V,Shutdown 0.4 V Logic-High V V IH V IN = 3V to 5.5V,Start-up 1.2 V Power Supply f = 100Hz -70 PSRR C Rejection Rate OUT = 1μF, I OUT = 10mA f = 10kHz -55 db Note 1: Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2: VIN(MIN)=VOUT+VDROPOUT Note 3: To prevent the Short Circuit Current protection feature from being prematurely activated, the input and enable voltage must be applied before a current source load is applied. Note 4: The dropout voltage is defined as (VIN-VOUT) when VOUT is 100mV below the target value of VOUT. Jan Rev 1.1

4 Pin Configurations (Top View) (T)SOT-23-5 / SC-70-5 TO-252-2L Pin Description (T)SOT-23-5 SC-70-5 TO-252-2L Name 1 1 VIN Input Voltage. 2 FIN GND Ground. Pin Function 3 EN Chip Enable (Active High). Note that this pin is high impedance. There should be a pull low 100K resistor connected to GND when the control signal is floating. 4 SS Soft Start. 5 3 VOUT Output Voltage. Function Block Diagram EN Shutdown and Logic Control VIN SS V REF + - Error Amplifier MOS Driver Current-Limit and Thermal Protection VOUT GND Jan Rev 1.1

5 Typical Operating Characteristics (Unless otherwise specified, V IN = V OUT + 1V, C IN = C OUT = 1μF, C SS = 1nF, T A = 25 C) Load Regulation Line Regulation Output Voltage (V) V OUT =3.1V Output Voltage (V) V OUT =3.1V I OUT = 10mA Output Current (ma) Input Voltage (V) 105 Input Voltage vs. Quiescent Current 1.00 Input Voltage vs. Shutdown Current Quiescent Current (μa) V OUT =3.1V V EN = V IN Shutdown Current (μa) V EN =GND Input Voltage (V) Input Voltage (V) 300 Dropout Voltage vs. Output Current 0.95 Input Voltage vs. Current Limit Dropout Voltage (mv) V OUT =3.1V Current Limit (A) V OUT Connect 0.1Ω to GND Output Current (ma) Input Voltage (V) Jan Rev 1.1

6 Enable Threshold Voltage vs. Temperature C SS Capacitor vs. Soft Start Time Enable Threshold Voltage (V) Input Voltage (V) Soft Start Time (ms) V IN = 5.0V, V OUT = 3.1V C SS Capacitor (nf) 80 PSRR 100 Region of Stable C OUT ESR vs. Output Current Instable PSRR (-db) 60 V OUT 3.1V, I LOAD = 10mA V OUT 3.1V, I LOAD = 50mA 50 V IN =4.1V DC +0.5V P-P ; C IN =C OUT =1 F K K K COUT -ESR (Ω) 1 Stable Simulation verify C IN = C OUT =1 F Frequency (Hz) Output Current (ma) Load Transient Response Load Transient Response V OUT (AC) (50.0mV/Div) V OUT (AC) (50.0mV/Div) I OUT (DC) (200mA/Div) V IN = 4.5V, V OUT = 3.1V, I OUT = 1mA to 300mA I OUT (DC) (200mA/Div) V IN = 5.0V, V OUT = 3.1V, I OUT = 1mA to 500mA Time (400μs/Div) Time (400μs/Div) Jan Rev 1.1

7 Line Transient Response Line Transient Response V OUT (AC) (10.0mV/Div) V OUT (AC) (10.0mV/Div) V IN DC) (1.00V/Div) V IN = 3.8V to 4.8V V OUT = 3.3V, I OUT = 10mA V IN (DC) (1.00V/Div) V IN = 3.8V to 4.8V V OUT = 3.3V, I OUT = 100mA Time (100μs/Div) Time (100μs/Div) Start-up from EN Start-up from V IN V EN (DC) V IN (DC) V OUT (DC) V OUT (DC) I IN (DC) (500mA/Div) I OUT =500mA (Resistive Load) V IN = 4.5V, V OUT = 3.1V, C SS =22nF I IN (DC) (500mA/Div) I OUT =500mA (Resistive Load) V IN = 4.5V, V OUT = 3.1V, C SS =22nF Time (5.00ms/Div) Time (5.00ms/Div) Shutdown from EN Shutdown from V IN V EN (DC) V IN (DC) V OUT (DC) I OUT =500mA (Resistive Load) V IN = 4.5V, V OUT = 3.1V, C SS =22nF V OUT (DC) I OUT =500mA (Resistive Load) V IN = 4.5V, V OUT = 3.1V, C SS =22nF Time (10.0μs/Div) Time (4.00ms/Div) Jan Rev 1.1

8 Shutdown from EN Shutdown from V IN V EN (DC) V IN (DC) V OUT (DC) I OUT =0mA V IN =4.5V, V OUT = 3.1V, C SS =22nF V OUT (DC) I OUT =0mA V IN =4.5V, V OUT = 3.1V, C SS =22nF Time (40.0μs/Div) Time (20.0ms/Div) Soft Start Time Short Circuit Operation V EN (DC) (5.00V/Div) T SS =8.7μs V IN (DC) (2V/Div) V OUT 90% V OUT (DC) (200mV/Div) V OUT (DC) I OUT =0mA V IN = V EN =4.3V, V OUT = 3.3V, C SS =NC I IN (DC) (200mA/Div) V OUT Connected to GND V IN = 4.5V, V OUT = 3.1V, C SS =1nF Time (2.00μs/Div) Time (2.5ms/Div) Jan Rev 1.1

9 Application Information Capacitor Selection and Regulator Stability Input Capacitor An input capacitance of 1μF is required between the device input pin and ground directly (the amount of the capacitance may be increased without limit). The input capacitor MUST be located less than 1 cm from the device to assure input stability (see PCB Layout Section). A lower ESR capacitor allows the use of less capacitance, while higher ESR type (like aluminum electrolytic) requires more capacitance. Capacitor types (aluminum, ceramic and tantalum) can be mixed in parallel, but the total equivalent input capacitance/esr must be defined as above for stable operation. There are no requirements for the ESR on the input capacitor, but tolerance and temperature coefficient must be considered when selecting the capacitor to ensure the capacitance is 1μF over the entire operating range. Output Capacitor The is designed specifically to work with very small ceramic output capacitors. The minimum capacitance recommended (temperature characteristics of X7R, X5R, Z5U or Y5V) is within the 1μF to 10μF range with 5mΩ to 50mΩ ESR range ceramic capacitor between LDO output and GND for transient stability, but it may be increased without limit. Higher capacitance values help to improve transient response. The output capacitor's ESR is critical because it forms a zero to provide phase lead which is required for loop stability. Enable Function The is shut down by pulling the EN pin low, and turned on by driving the input high. If the shutdown feature is not required, the EN pin should be tied to VIN to keep the regulator on at all times (the EN pin MUST NOT be left floating). To assure proper operation, the signal source used to drive the EN pin must be able to swing above and below the specified turn-on/off voltage thresholds listed in the Electrical Characteristics under VIH and VIL. The ON/OFF signal may come from either CMOS output, or an open-collector output with pull-up resistor to the device input voltage or another logic supply. The highlevel voltage may exceed the device input voltage, but must remain within the absolute maximum ratings for the EN pin. Operating Region and Power Dissipation Since the is a linear regulator, its power dissipation is always given by P = I OUT (V IN V OUT ). The maximum power dissipation is given by: P D(MAX) = (T J T A ) /θ JA =(125 C -25 C)/250 C/W = 400mW Where (T J T A ) is the temperature difference the die and the ambient air, θ JA is the thermal resistance of the chosen package to the ambient air. For surface mount device, heat sinking is accomplished by using the heat spreading capabilities of the PC board and its copper traces. In the case of a SOT-23-5 package, the thermal resistance is typically 250 C /Watt. Refer to Figure 1 & 2 for the valid operating region (Safe Operating Area) and refer to Figure 3 for maximum power dissipation information of SOT The die attachment area of the lead frame is connected to pin 2, which is the GND pin. Therefore, the GND pin of can dissipate the heat from the die very effectively. To improve the maximum power providing capability, connect the GND pin to ground using a large ground plane near the GND pin. Short Circuit Current Fold-Back This feature becomes active when the output drops below 200mV, and reduces the current flow by 80%. Full current is restored when the voltage exceeds 200mV. Jan Rev 1.1

10 Output Current IOUT (ma) Safe Operation Area of I OUT =150mA [Power Dissipation Limit] Still air SOT-23-5 package Mounted on recommended footprint ( JA =250 C/W) T A =85 C Input-Output Voltage Differential V IN -V OUT (V) Fig. 1 T A =55 C T A =25 C Output Current IOUT (ma) Safe Operation Area of I OUT =300mA [Power Dissipation Limit] Still air SOT-23-5 package Mounted on recommended footprint ( JA =250 C/W) T A =85 C T A =25 C Input-Output Voltage Differential V IN -V OUT (V) Fig. 2 T A =55 C 0.5 Maximum Power Dissipation Power Dissipation PD(W) Still air SOT-23-5/SC-70-5 package Mounted on recommended footprint SC-70-5 SOT Ambient Temperature T A ( C) Fig. 3 Jan Rev 1.1

11 Packaging SC-70-5 DIMENSIONS IN SYMBOLS MILLIMETERS DIMENSIONS IN INCH MIN NOM MAX MIN NOM MAX A A A b C D E E e 0.65 BSC BSC. e BSC BSC. L REF REF. Jan Rev 1.1

12 SOT-23-5 SYMBOLS DIMENSIONS IN MILLIMETERS DIMENSIONS IN INCH MIN NOM MAX MIN NOM MAX A A A b C D E e (TYP) H L Θ e (TYP) Jan Rev 1.1

13 TSOT-23-5 SYMBOLS DIMENSIONS IN MILLIMETERS DIMENSIONS IN INCH MIN NOM MAX MIN NOM MAX A A A A b C D E e (TYP) (TYP) --- H L Θ e (TYP) Jan Rev 1.1

14 TO-252-2L SYMBOLS DIMENSIONS IN MILLIMETERS DIMENSIONS IN INCH MIN NOM MAX MIN NOM MAX A A b b c c D E D E e e H L L L Jan Rev 1.1

15 Footprints (T)SOT-23-5 Footprint Dimension (mm) Package Number of PIN Tolerance P1 P2 A B C D M SOT ±0.10 SC-70-5 Footprint Dimension (mm) Package Number of PIN Tolerance P1 P2 A B C D M SC ±0.10 Jan Rev 1.1

16 TO-252-2L Footprint Dimension (mm) Package Number of PIN Tolerance P A B C D M TO-252-2L ±0.10 Jan Rev 1.1