AAT4611 Current Limited Load Switch in SOT23 Package General Description Features The AAT4611 SmartSwitch is a current limited Pchannel MOSFET power switch designed for highside load switching applications. This switch operates with inputs ranging from 2.7V to 5.5V, making it ideal for both 3V and 5V systems. An integrated current-limiting circuit protects the input supply against large currents which may cause the supply to fall out of regulation. The AAT4611 is also protected from thermal overload which limits power dissipation and junction temperatures. It can be used to control loads that require up to 1A. Current limit threshold is programmed with a resistor from SET to ground. The quiescent supply current is typically a low 15µA max. In shutdown mode, the supply current decreases to less than 1µA. • • • The AAT4611 is available in a Pb-free 5-pin SOT23 package and is specified over the -40°C to +85°C temperature range. • • • • • • • • SmartSwitch™ Input Voltage Range: 2.7V to 5.5V Programmable Over-Current Threshold Fast Transient Response: — <1µs Response to Short Circuit Low Quiescent Current — 15µA Typical — 1µA Max with Switch Off 160mΩ Typical RDS(ON) Only 2.5V Needed for ON/OFF Control Under-Voltage Lockout Thermal Shutdown 4kV ESD Rating 5-Pin SOT23 Package Temperature Range: -40°C to +85°C Applications • • • • Hot Swap Supplies Notebook Computers Peripheral Ports Personal Communication Devices Typical Application INPUT OUTPUT IN OUT AAT4611 ON (ON) SET ON/(ON) GND 1µF GND 4611.2006.09.1.4 RSET 0.47µF GND 1 AAT4611 Current Limited Load Switch in SOT23 Package Pin Descriptions Pin # Symbol Function 1 OUT P-channel MOSFET drain. Connect a 0.47µF capacitor from OUT to GND. 2 GND Ground connection. 3 SET Current limit set input. A resistor from SET to ground sets the current limit for the switch. 4 ON Enable input. Two versions are available, active-high and active-low. See Ordering Information for details. 5 IN P-channel MOSFET source. Connect a 1µF capacitor from IN to GND. Pin Configuration 2 SOT23-5 (Top View) OUT 1 GND 2 SET 3 5 IN 4 ON 4611.2006.09.1.4 AAT4611 Current Limited Load Switch in SOT23 Package Absolute Maximum Ratings1 TA = 25°C, unless otherwise noted. Symbol Description VIN VON VSET, VOUT IMAX TJ TLEAD VESD IN to GND ON(ON) to GND SET, OUT to GND Maximum Continuous Switch Current Operating Junction Temperature Range Maximum Soldering Temperature (at leads) ESD Rating2 - HBM Value Units -0.3 to 6 -0.3 to VIN + 0.3 -0.3 to VIN + 0.3 2 -40 to 150 300 4000 V V V A °C °C V Value Units 150 667 °C/W mW Thermal Characteristics3 Symbol ΘJA PD Description Thermal Resistance Power Dissipation 1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. 3. Mounted on a demo board. 4611.2006.09.1.4 3 AAT4611 Current Limited Load Switch in SOT23 Package Electrical Characteristics VIN = 5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are TA = 25°C. Symbol VIN IQ 4 Description IQ(OFF) ISD(OFF) VUVLO Operation Voltage Quiescent Current Off-Supply Current Off-Switch Current Under-Voltage Lockout RDS(ON) On Resistance ILIM ILIM(MIN) VON(L) Current Limit Minimum Current Limit ON (ON) Input Low Voltage VON(H) ON (ON) Input High Voltage ION(SINK) TRESP TOFF TON ON (ON) Input Leakage Current Limit Response Time Turn-Off Time Turn-On Time Conditions Min Typ 2.7 VIN = 5V, ON (ON) = Active, IOUT = 0 ON (ON) = Inactive, VIN = 5.5V ON (ON) = Inactive, VIN = 5.5V, VOUT = 0 Rising Edge, 1% Hysteresis VIN = 5.0V VIN = 4.5V VIN = 3.0V RSET = 6.8kΩ VIN = 2.7V to 3.6V VIN = 4.5V to 5.5V VON = 5.5V VIN = 5V VIN = 5V, RL = 10Ω VIN = 5V, RL = 10Ω 15 2.0 0.75 0.03 2.3 160 165 195 1 130 Max Units 5.5 30 1 15 2.7 180 V µA µA µA V mΩ 230 1.25 195 0.8 2.0 2.4 A mA V V 0.01 0.8 0.4 40 1 2 200 µA µs µs µs 4611.2006.09.1.4 AAT4611 Current Limited Load Switch in SOT23 Package Typical Characteristics Unless otherwise noted, VIN = 5V, TA = 25°C. Quiescent Current 40 25 Input Current (µA) Quiescent Current (μA) Quiescent Current vs. Temperature 20 15 10 5 0 -40 -20 0 20 40 60 80 100 120 Temperature (°C) 30 20 10 0 2.5 3 3.5 Output Current vs. Output Voltage (RSET = 16kΩ) 5 5.5 250 Input = 3V 200 RDS(ON) (mΩ) Output Current (A) 4.5 RDS(ON) vs. Temperature 0.6 0.4 0.2 150 Input = 5V 100 50 0 0 0 1 2 3 4 -40 5 -20 0 Off-Supply Current vs. Temperature 40 60 80 100 Off-Switch Current vs. Temperature 10 Off-Switch Current (µA) 10 1 0.1 0.01 -40 20 Temperature (°C) Output Voltage (V) Off-Supply Current (µA) 4 Input Voltage (V) -20 0 20 40 60 Temperature (°C) 4611.2006.09.1.4 80 100 120 1 0.1 0.01 0.001 -40 -20 0 20 40 60 80 100 120 Temperature (°C) 5 AAT4611 Current Limited Load Switch in SOT23 Package Typical Characteristics Unless otherwise noted, VIN = 5V, TA = 25°C. Turn-On vs. Temperature Turn-Off vs. Temperature 0.45 0.4 Turn-Off Time (µs) Turn-On Time (µs) 80 70 VIN = 3V 60 50 40 30 VIN = 5V 20 10 VIN = 3V 0.35 0.3 0.25 VIN = 5V 0.2 0.15 0.1 0.05 0 0 - 40 - 20 0 20 40 60 80 - 40 100 - 20 0 Temperature (°C) ON Output 3 2 1 3 2 1 0 0 -1 - 20 -1 - 0.5 40 60 ON Output 0 Time (µs) 2 0 Output Voltage 0 -4 2 3 Input and Output Voltage (V) 4 Output Current Time (µs) 6 8 9 8 6 6 Input Voltage 3 4 Output Current 0 2 Output Voltage Output Current (A) Input Voltage Output Current (A) Input and Output Voltage (V) 12 1 1 Short-Circuit Through 0.6Ω 8 0 0.5 Time (µs) Short-Circuit Through 0.3Ω 4 100 4 Voltage (V) Voltage (V) 6 5 6 80 Turn-Off 6 20 60 (RL = 10Ω; IOUT = ILIMIT) 5 0 40 Temperature (°C) Turn-On (RL = 10Ω; CL = 0.47μF; IOUT = ILIMIT) 4 20 -3 0 0 1 2 3 Time (µs) 4611.2006.09.1.4 AAT4611 Current Limited Load Switch in SOT23 Package Typical Characteristics Unless otherwise noted, VIN = 5V, TA = 25°C. RSET Coefficient vs. ILIM RSET vs. ILIM 10 RSET ILIM Product (kV) RSET (kΩ) 100 10 9 8 7 6 5 1 0.1 1 10 0 0.5 1 1.5 2 ILIM (A) ILIM (A) Current Limit vs. Temperature (RSET = 22.1kΩ; VIN - VOUT = 0.5V) Current Limit (%) 6% 4% 2% 0% -2% -4% -6% -50 - 25 0 25 50 75 100 Temperature (°C) 4611.2006.09.1.4 7 AAT4611 Current Limited Load Switch in SOT23 Package Functional Block Diagram IN OUT Over-Temperature Protection UnderVoltage Lockout ON (ON) 1.2V Reference Current Limit SET RSET GND Applications Information 1.2 Setting Current Limit 8 0.8 ILIM (A) In most applications, the variation in ILIM must be taken into account when determining RSET. The ILIM variation is due to processing variations from part to part, as well as variations in the voltages at IN (Pin 5) and OUT (Pin 1) and the operating temperature. See charts "Current Limit vs. Temperature" and "Output Current vs. Output Voltage." Together, these three factors add up to a ±25% tolerance (see ILIM specification in Electrical Characteristics section). In Figure 1, a cold device with a statistically higher current limit and a hot device with a statistically lower current limit, both with RSET equal to 10.5kΩ, are shown. While the chart, "RSET vs. ILIM" indicates an ILIM of 0.7A with an RSET of 10.5kΩ, this figure shows that the actual current limit will be at least 0.525A and no greater than 0.880A. Device With High Current Limit at -40°C 0.88A 1 0.6 0.525A 0.4 Device With Low Current Limit at 85°C 0.2 0 0 1 2 3 4 5 Output Voltage (V) Ω. Figure 1: Current Limit Using 10.5kΩ To determine RSET, start with the maximum current drawn by the load and multiply it by 1.33 (typical ILIM = minimum ILIM / 0.75). This is the typical current limit value. Next, refer to "RSET vs. ILIM" and find the RSET that corresponds to the typical current limit value; choose the largest resistor available that is less than or equal to it. For greater precision, the value of RSET may also be calculated using the ILIM RSET product found in the chart "RSET Coefficient vs. 4611.2006.09.1.4 AAT4611 Current Limited Load Switch in SOT23 Package ILIM." The maximum current is derived by multiplying the typical current for the chosen RSET in the chart by 1.25. Some standard resistor values are listed in Table 1. RSET Ω) (kΩ 40.2 30.9 24.9 22.1 19.6 17.8 16.2 14.7 13.0 10.5 8.87 7.50 6.81 6.04 5.49 4.99 4.64 typical ILIM value for 10.5kΩ. Multiplying 0.7A by 0.75 and 1.25 shows that the AAT4611 will limit the load current to greater than 0.525A but less than 0.875A. Operation in Current Limit Current Device Will Device Always Limit Not Current Current Limits (Typ) Limit Below Below (mA) (mA) (mA) 200 250 300 350 400 450 500 550 600 700 800 900 1000 1100 1200 1300 1400 150 188 225 263 300 338 375 413 450 525 600 675 750 825 900 975 1050 When a heavy load is applied to the output of the AAT4611, the load current is limited to the value of ILIM determined by RSET (see Figure 2). Since the load is demanding more current than ILIM, the voltage at the output drops. This causes the AAT4611 to dissipate a larger-than-normal quantity of power, and causes the die temperature to increase. When the die temperature exceeds an over-temperature limit, the AAT4611 will shut down until is has cooled sufficiently, at which point it will start up again. The AAT4611 will continue to cycle on and off until the load is removed, power is removed, or until a logic high level is applied to ON (Pin 4). 250 313 375 438 500 563 625 688 750 875 1000 1125 1250 1375 1500 1625 1750 Enable Input In many systems, power planes are controlled by integrated circuits which run at lower voltages than the power plane itself. The enable input ON (Pin 4) of the AAT4611 has low and high threshold voltages that accommodate this condition. The threshold voltages are compatible with 5V TTL and 2.5V to 5V CMOS. Table 1: Current Limit RSET Values. Reverse Voltage Example: A USB port requires 0.5A. 0.5A multiplied by 1.33 is 0.665A. From the chart "RSET vs. ILIM," RSET should be less than 11kΩ. 10.5 kΩ is a standard value that is slightly less than, but very close to, 11kΩ. The chart gives approximately 0.7A as a The AAT4611 is designed to control current flowing from IN to OUT. If a voltage is applied to OUT which is greater than the voltage on IN, large currents may flow. This could cause damage to the AAT4611. 1 0.5 0.25 0 5 Output Current 4 3 1Ω Load is Turned On at Time = 0 Output Voltage 2 Output Current (A) Output Voltage (V) 0.75 1 0 -0.05 0 0.05 0.1 0.15 0.2 0.25 0.3 Time (s) Figure 2: Overload Operation. 4611.2006.09.1.4 9 AAT4611 Current Limited Load Switch in SOT23 Package Ordering Information Package Enable Marking1 Part Number (Tape and Reel)2 SOT23-5 ON (active low) CLXYY AAT4611IGV-T1 SOT23-5 ON (active high) All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at http://www.analogictech.com/pbfree. Package Information SOT23-5 2.85 ± 0.15 1.90 BSC 0.40 ± 0.10 0.075 ± 0.075 0.15 ± 0.07 4° ± 4° 10° ± 5° 1.10 ± 0.20 0.60 REF 1.20 ± 0.25 2.80 ± 0.20 1.575 ± 0.125 0.95 BSC 0.60 REF 0.45 ± 0.15 GAUGE PLANE 0.10 BSC All dimensions in millimeters. 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. © Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’s standard warranty. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders. Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 10 4611.2006.09.1.4