Advanced Analog Technology, Inc. AAT1204 400-mA MULTI-INPUT LOW-DROPOUT REGULATOR WITH VAUX SWITCH Features z Complete Power Management z Automatic Input Voltage Selection z Input Voltage Source Detector With Hysteresis z 400-mA Load Current Capability With VCC50 or VSB50 or AUX33 Input Source z Integrated Low rDS (on) Switch z Regulated Output 3.3V (fixed) z Output Short Circuit Protection Pin Configuration TOP VIEW VSB50 1 8 GND VCC50 2 7 GND OUT33 3 6 GND AUX33 4 5 GND ( 8-PIN SOIC ) Description The AAT1204 is a multi-input low-dropout regulator that provides constant output supply 3.3V at the output capable of driving a 400-mA load. The AAT1204 provides regulated power output for systems that have multiple input sources and require constant voltage source with a low-dropout voltage. This is a intelligent power source selection device with a low-dropout regulator for either VCC50 or VSB50 inputs, and a low-resistance bypass switch for the AUX33 input. Transitions may occur from one input supply to another without generating a glitch outside of the specification range on the 3.3-V output. The device has an incorporated reverse-blocking scheme to prevent excess leakage from the input terminals in the event that the output voltage is greater than the input voltage. The input voltage is prioritized in the following order: VCC50, VSB50, AUX33. – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 Functions Table INPUT VOLTAGE STATUS (V) VCC50 0 0 0 0 5 5 5 5 VSB50 0 0 5 5 0 0 5 5 AUX33 0 3.3 0 3.3 0 3.3 0 3.3 INPUT SELECTED OUTPUT （V） VCC50/VSB50/AUX33 None AUX33 VSB50 VSB50 VCC50 VCC50 VCC50 VCC50 OUT33 0 3.3 3.3 3.3 3.3 3.3 3.3 3.3 OUTPUT （I）（mA） Iout33 0 400 400 400 400 400 400 400 PIN Description TERMINAL NAME NO. VSB50 VCC50 OUT33 AUX33 GND GND GND GND 1 2 3 4 5 6 7 8 I/O I I O I I I I I Description 5-V standby supply input 5-V main supply input 3.3-V regulated output 3.3-V auxiliary supply input Ground Ground Ground Ground absolute maximum ratings┼ • Main Supply voltage, V（VCC50）…………….…….………………………………... -0.5V~7V • Standby Supply voltage, V（VSB50）……………….………………………………… -0.5V~7V • Auxiliary Supply voltage, V（AUX33）…………….……………………….…....….... -0.5V~7V • Output current limit, I（LIMIT）………………………………….…………….…………... 1.5A • Continuous power dissipation, PD（see Note 1）…………….…………………….….. 1.1W • Electrostatic discharge susceptibility, human body model………………….……….…....2kV • Operating ambient temperature range, TA……………….……………..…………0℃ to 70℃ • Storage temperature range, Tstg…………….…………….…………………..-55℃ to 150℃ • Operating junction temperature range, TJ…………….………………...……....-5℃ to 135℃ • Lead temperature （soldering, 10 second）,T（LEAD）………………….…………..…...260℃ NOTE 1：The device deteriorate with increase in ambient temperature, TA. See Thermal Information section. – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 Recommended operating conditions Min 4.5 4.5 3 4.23 0 0 5-V main supply input, VCC50 5-V standby supply input, VSB50 3.3V auxiliary supply input, AUX33 Load capacitance, CL Load current, IL Ambient temperature, TA Typ 4.7 Max 5.5 5.5 3.6 5.17 400 70 Unit V V V µF mA ℃ Electrical Characteristics over recommended operating free-air temperature, TA = 0℃ to 70 ℃,CL = 4.7µF (unless otherwise noted) Parameter VCC50 VSB50 OUT33 △VO（△VI） △VO（△IO） I50 Test Condition 5-V inputs 3.3-V output Line regulation voltage Load regulation voltage Quiescent supply current Iout33 = 400mA VSB50 or VCC50 = 4.5V to 5.5V 20 mA＜IL＜400 mA From VCC50 VSB50 terminals, IL= 0 to 400mA From AUX33 terminal, IL = 0A IAUX IL33 ILIMIT Out33 load current Output current limit TTSD Thermal shutdown（NOTE 2） Thys Thermal hysteresis（NOTE2） CL Load capacitance Min Typ 4.5 5 Max Unit 5.5 V 3.135 3.3 2 40 3.465 V mV mV 1.0 3.0 mA 1.0 3.0 mA 0.4 Out33 output short to 0v 150 180 ℃ 15 Minimal ESR to insure stability of regulated output Reverse leakage output current Tested for input that is grounded. AUX33, VSB50 or VCC50 = GND, Out33 = 3.3v VLO Threshold voltage, low VSB50 or VCC50↓ VHI Threshold voltage, high VSB50 or VCC50↑ VSB50 = VCC50 = 0V, R（SWITCH） Auxiliary switch resistance AUX33 = 3.3V, IL = 150mA RθJA Thermal impedance, Without copper for heat spreading Junction-to-ambient（NOTE3） With copper for heat spreading A 1.5 4.7 IIkg（REV） 4.0 4.25 4.2 4.45 100 70 μF 50 μA 4.4 4.65 0.4 V V Ω ℃/W NOTE 2：Design targets only. Not tested in production. NOTE 3：Please refer to "Thermal Information" – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 VCC50 VSB50 3.3V + + - - VCC50 Detector AUX33 Control 3.3V VSB50 Detector Low on Resistance OUT33 GND GND GND OVER TEMPERATURE PROTECTION GND – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 TYPICAL CHARACTERISTICS Figure 1. 3.3V VCC50 Cold Start Figure 2. 3.3V AUX33 Cold Start – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 TYPICAL CHARACTERISTICS Figure 3. Figure 4. 3.3V VCC50 Power Up(VSB50=5V) 3.3V VCC50 Power Up(AUX33=3.3V) – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 TYPICAL CHARACTERISTICS Figure 5. 3.3V VSB50 Power Up(AUX33=3.3V) Figure 6. 3.3V VCC50 Power Down(VSB=5V) – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 TYPICAL CHARACTERISTICS Figure 7. 3.3V VCC50 Power Down(AUX33=3.3V) Figure 8. 3.3V Load Transient Response Falling. TYPICAL CHARACTERISTICS – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 Figure 9. 3.3V Load Transient Response Rising – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 THERMAL INFORMATION To ensure reliable operation of the device, the junction temperature of the output device must be within the safe operating area（SOA）. This is achieved by having a means to dissipate the heat generated from the junction of the output structure. There are two components that contribute to thermal resistance. They consist of two paths in series. The first is the junction to case thermal resistance, RJC; the second is the case to ambient thermal resistance, RCA. The overall junction to ambient thermal resistance, RJA, is determined by： RJA＝RJC＋RCA The ability to efficiently dissipate the heat from the junction is a function of the package style and board layout incorporated in the application. The operating junction temperature is determined by the operation ambient temperature, TA, and the junction power dissipation, PJ. The junction temperature, TJ, is equal to the following thermal equation： TJ＝TA＋PJ（RJC）＋PJ（RCA） TJ＝TA＋PJ（RJA） This particular application uses the 8-pin SO package with standard lead frame with a dedicated ground terminal. Hence, the maximum power dissipation allowable for an operating ambient temperature of 70℃, and a maximum junction temperature of 150℃ is determined as： PJ＝（TJ－TA）/ RJA PJ＝（150－70）/70＝1.1W Worst case maximum power dissipation is determined by： PD＝（5.5－3.135）×0.4＝0.946W Normal operating maximum power dissipation is： PD＝（5－3.3）×0.4＝0.68W Note: The thermal characteristics of the AAT1204 were measured using a double-sided board with two square inches of copper area connected to the GND pins for "heat spreading". The use of multi-layer board construction with power planes will further enhance the thermal performance of the package. – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 THERMAL INFORMATION Power-W 1.78 0.946 0.68 25 83 102 150 Ambient Temperature - °C NOTE: These curves are to be used for guideline purposes only. For a particular application, a more specijic thermal characterization is required. Power Dissipation Derating Curves – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 APPLICATION INFORMATION 1 8 VSB50 GND VCC50 GND GND 4.7μF 0.1μF 2 4.7μF 0.1μF 3 7 AAT1204 OUT33 3.3V GND 6 GND GND 4.7μF 5 4 AUX33 4.7μF GND GND 0.1μF Typical Application Schematic – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0 Advanced Analog Technology, Inc. AAT1204 Package Dimension θ L D E1 7°(4X) A1 8REF. 7°(4X) 6(MIN) 50TYP. B eB Symbol A A1 B D E1 eB L θ Dimension in mils Min Nom Max 59 63 67 22 24 26 12 16 20 188 190 192 152 154 156 229 235 241 24 --- 0º 3º 6º Dimension in Min Nom 1.498 1.600 0.56 0.610 0.305 0.406 4.775 4.826 3.861 3.912 5.816 5.969 0.6 -- 0º 3º mm Max 1.702 0.66 0.508 4.877 3.962 6.121 -- 6º – 台灣類比科技股份有限公司 – Advanced Analog Technology, Inc. V 1.0