800mA LOW DROPOUT VOLTAGE REGULATOR

Advanced Monolithic Systems FEATURES • Three Terminal Adjustable or Fixed Voltages* 1.5V, 1.8V, 2.5V, 2.85V, 3.3V and 5.0V • Output Current of 800mA • Operates Down to 1V Dropout • Line Regulation: 0.2% Max. • Load Regulation: 0.4% Max. • SOT-223 and TO-252 package available AMS1117 800mA LOW DROPOUT VOLTAGE REGULATOR APPLICATIONS • High Efficiency Linear Regulators • Post Regulators for Switching Supplies • 5V to 3.3V Linear Regulator • Battery Chargers • Active SCSI Terminators • Power Management for Notebook • Battery Powered Instrumentation GENERAL DESCRIPTION The AMS1117 series of adjustable and fixed voltage regulators are designed to provide 800mA output current and to operate The down to 1V input-to-output differential. The dropout voltage of the device is guaranteed maximum 1.3V at maximum output current, decreasing at lower load currents. On-chip trimming adjusts the reference voltage to 1%. Current limit is also trimmed, minimizing the stress under overload conditions on both the regulator and power source circuitry. The AMS1117 devices are pin compatible with other three-terminal SCSI regulators and are offered in the low profile surface mount SOT-223 package and in the TO-252 (DPAK) plastic package. ORDERING INFORMATION: PACKAGE TYPE OPERATING JUNCTION TO-252 SOT-223 TEMPERATURE RANGE AMS1117CD AMS1117 0 to 125° C AMS1117CD-1.5 AMS1117-1.5 0 to 125° C AMS1117CD-1.8 AMS1117-1.8 0 to 125° C AMS1117CD-2.5 AMS1117-2.5 0 to 125° C AMS1117CD-2.85 AMS1117-2.85 0 to 125° C AMS1117CD-3.3 AMS1117-3.3 0 to 125° C AMS1117CD-5.0 AMS1117-5.0 0 to 125° C *For additional available fixed voltages contact factory. SOT-223 Top View 1 2 3 PIN CONNECTIONS FIXED VERSION 1- Ground 2- VOUT 3- VIN ADJUSTABLE VERSION 1- Adjust 2- VOUT 3- VIN TAB IS OUTPUT TO-252 FRONT VIEW 3 2 1 Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140 AMS1117 ABSOLUTE MAXIMUM RATINGS (Note 1) Power Dissipation Internally limited Input Voltage 15V Operating Junction Temperature Range Control Section 0°C to 125°C Power Transistor 0°C to 150°C Storage temperature - 65°C to +150°C Soldering information Lead Temperature (10 sec) Thermal Resistance TO-252 package SOT-223 package 300°C ϕ JA= 80°C/W ϕ JA= 90°C/W* * With package soldering to copper area over backside ground plane or internal power plane ϕ JA can vary from 46°C/W to >90°C/W depending on mounting technique and the size of the copper area. ELECTRICAL CHARACTERISTICS Electrical Characteristics at IOUT = 0 mA, and TJ = +25°C unless otherwise specified. Parameter Reference Voltage (Note 2) Output Voltage (Note 2) Device AMS1117 AMS1117-1.5 AMS1117-1.8 AMS1117-2.5 AMS1117-2.85 AMS1117-3.3 AMS1117-5.0 Conditions IOUT = 10 mA 10mA ≤ IOUT ≤ 800mA, 1.5V≤ (VIN - VOUT) ≤ 12V 0 ≤ IOUT ≤ 800mA , 3.0V≤ VIN ≤ 12V 0 ≤ IOUT ≤ 800mA , 3.3V≤ VIN ≤ 12V 0 ≤ IOUT ≤ 800mA , 4.0V≤ VIN ≤ 12V 0 ≤ IOUT ≤ 800mA , 4.35V≤ VIN ≤ 12V 0 ≤ IOUT ≤ 800mA , 4.75V ≤ VIN ≤ 12V 0 ≤ IOUT ≤ 800mA , 6.5V ≤ VIN ≤ 12V ILOAD = 10 mA , 1.5V≤ (VIN - VOUT) ≤ 12V 3.0V≤ VIN ≤ 12V 3.3V≤ VIN ≤ 12V 4.0V≤ VIN ≤ 12V 4.35V≤ VIN ≤ 12V 4.75V≤ VIN ≤ 12V 6.5V≤ VIN ≤ 12V (VIN - VOUT) =3V, 10mA ≤ IOUT ≤ 800mA VIN = 5V, 0 ≤ IOUT ≤ 800mA VIN = 5V, 0 ≤ IOUT ≤ 800mA VIN = 5V, 0 ≤ IOUT ≤ 800mA Min 1.238 1.225 1.485 1.476 1.782 1.773 2.475 2.460 2.82 2.79 3.267 3.235 4.950 4.900 Typ 1.250 1.250 1.500 1.500 1.800 1.800 2.500 2.500 2.850 2.850 3.300 3.300 5.000 5.000 0.015 0.035 0.3 0.6 0.3 0.6 0.3 0.6 0.3 0.6 0.5 1.0 0.5 1.0 0.1 0.2 3 6 3 6 3 6 Max 1.262 1.270 1.515 1.524 1.818 1.827 2.525 2.560 2.88 2.91 3.333 3.365 5.050 5.100 0.2 0.2 5 6 5 6 6 6 6 6 10 10 10 10 0.3 0.4 10 20 10 20 12 20 Units V V V V V V V V V V V V V V % % mV mV mV mV mV mV mV mV mV mV mV mV % % mV mV mV mV mV mV Line Regulation AMS1117 AMS1117-1.5 AMS1117-1.8 AMS1117-2.5 AMS1117-2.85 AMS1117-3.3 AMS1117-5.0 Load Regulation (Notes 2, 3) AMS1117 AMS1117-1.5 AMS1117-1.8 AMS1117-2.5 Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140 AMS1117 ELECTRICAL CHARACTERISTICS Electrical Characteristics at IOUT = 0 mA, and TJ = +25°C unless otherwise specified. Parameter Load Regulation (Notes 2, 3) Device AMS1117-2.85 AMS1117-3.3 AMS1117-5.0 Conditions VIN = 5V, 0 ≤ IOUT ≤ 800mA VIN = 5V, 0 ≤ IOUT ≤ 800mA VIN = 8V, 0 ≤ IOUT ≤ 800mA ∆VOUT , ∆VREF = 1%, IOUT = 800mA (Note 4) (VIN - VOUT) = 5V (VIN - VOUT) = 12V (Note 5) VIN ≤ 12V Min Typ 3 6 3 7 5 10 1.1 Max 12 20 15 25 20 35 1.3 1,500 10 10 Units mV mV mV mV mV mV V mA mA mA dB dB dB dB Dropout Voltage (VIN - VOUT) Current Limit Minimum Load Current Quiescent Current Ripple Rejection AMS1117-1.5/-1.8/-2.5/2.85/-3.3/-5.0 AMS1117-1.5/-1.8/-2.5/2.85/-3.3/-5.0 AMS1117 AMS1117-1.5/-1.8/-2.5/2.85/-3.3/-5.0 AMS1117 AMS1117-1.5/-1.8/-2.5/2.85 AMS1117-3.3 AMS1117-5.0 900 1,100 5 5 f =120Hz , COUT = 22µF Tantalum, IOUT = 800mA, (VIN-VOUT ) = 3V, CADJ =10µF f =120Hz , COUT = 22µF Tantalum, IOUT = 800mA, VIN = 6V f =120Hz , COUT = 22µF Tantalum, IOUT = 800mA VIN = 6.3V f =120Hz , COUT = 22µF Tantalum, IOUT = 800mA VIN = 8V TA = 25°C, 30ms pulse 10mA ≤ IOUT ≤ 800mA , 1.5V≤ (VIN - VOUT) ≤ 12V 10mA ≤ IOUT ≤ 800mA , 1.5V≤ (VIN - VOUT) ≤ 12V 60 60 60 60 75 72 72 68 0.008 55 120 0.2 0.5 5 0.04 Thermal Regulation Adjust Pin Current Adjust Pin Current Change Temperature Stability Long Term Stability RMS Output Noise (% of VOUT ) Thermal Resistance Junction-to-Case AMS1117 AMS1117 AMS1117 %W µA µA µA % TA =125°C, 1000Hrs TA = 25°C , 10Hz ≤ f ≤ 10kHz 0.3 0.003 1 % % 15 °C/W Parameters identified with boldface type apply over the full operating temperature range. Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Note 2: Line and Load regulation are guaranteed up to the maximum power dissipation of 1.2 W. Power dissipation is determined by the input/output differential and the output current. Guaranteed maximum power dissipation will not be available over the full input/output range. Note 3: See thermal regulation specifications for changes in output voltage due to heating effects. Line and load regulation are measured at a constant junction temperature by low duty cycle pulse testing. Load regulation is measured at the output lead ~1/8” from the package. Note 4: Dropout voltage is specified over the full output current range of the device. Note 5: Minimum load current is defined as the minimum output current required to maintain regulation. When 1.5V ≤ (VIN - VOUT) ≤ 12V the device is guaranteed to regulate if the output current is greater than 10mA. Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140 AMS1117 APPLICATION HINTS The AMS1117 series of adjustable and fixed regulators are easy to use and are protected against short circuit and thermal overloads. Thermal protection circuitry will shut-down the regulator should the junction temperature exceed 165°C at the sense point. Pin compatible with older three terminal adjustable regulators, these devices offer the advantage of a lower dropout voltage, more precise reference tolerance and improved reference stability with temperature. D1 VIN AMS1117 IN OUT ADJ CADJ VOUT R1 R2 + COUT 22µF Stability The circuit design used in the AMS1117 series requires the use of an output capacitor as part of the device frequency compensation. The addition of 22µF solid tantalum on the output will ensure stability for all operating conditions. When the adjustment terminal is bypassed with a capacitor to improve the ripple rejection, the requirement for an output capacitor increases. The value of 22µF tantalum covers all cases of bypassing the adjustment terminal. Without bypassing the adjustment terminal smaller capacitors can be used with equally good results. To ensure good transient response with heavy load current changes capacitor values on the order of 100µF are used in the output of many regulators. To further improve stability and transient response of these devices larger values of output capacitor can be used. 10µF Figure 1. Output Voltage The AMS1117 series develops a 1.25V reference voltage between the output and the adjust terminal. Placing a resistor between these two terminals causes a constant current to flow through R1 and down through R2 to set the overall output voltage. This current is normally the specified minimum load current of 10mA. Because IADJ is very small and constant it represents a small error and it can usually be ignored. AMS1117 IN OUT ADJ IADJ 50µA VIN Protection Diodes Unlike older regulators, the AMS1117 family does not need any protection diodes between the adjustment pin and the output and from the output to the input to prevent over-stressing the die. Internal resistors are limiting the internal current paths on the AMS1117 adjustment pin, therefore even with capacitors on the adjustment pin no protection diode is needed to ensure device safety under short-circuit conditions. Diodes between the input and output are not usually needed. Microsecond surge currents of 50A to 100A can be handled by the internal diode between the input and output pins of the device. In normal operations it is difficult to get those values of surge currents even with the use of large output capacitances. If high value output capacitors are used, such as 1000µF to 5000µF and the input pin is instantaneously shorted to ground, damage can occur. A diode from output to input is recommended, when a crowbar circuit at the input of the AMS1117 is used (Figure 1). VOUT VREF R1 R2 VO