AAT4610B PRODUCT DATASHEET. Current Limited Load Switch AAT4610B SOT23-5. General Description. Features. Applications. Typical Application

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1 General Description The AATB SmartSwitch is a current limited P-channel MOSFET power switch designed for high-side load switching applications. This switch operates with inputs ranging from.v to.v, making it ideal for both V and V systems. An integrated current-limiting circuit protects the input supply against large currents which may cause the supply to fall out of regulation. The AATB is also protected from thermal overload which limits power dissipation and junction temperatures. It can be used to control loads that require up to A. Current limit threshold is programmed with a resistor from SET to ground. The quiescent supply current is typically a low 9μA. In shutdown mode, the supply current decreases to less than μa. The AATB is available in a Pb-free -pin SOT or 8-pin SC7JW package and is specified over the - C to +8 C temperature range. Features AATB Input Voltage Range:.V to.v Programmable Over-Current Threshold Fast Transient Response: ns Response to Short Circuit Low Quiescent Current 9μA Typical μa Max with Switch Off mω Typical R DS(ON) Only.V Needed for ON/OFF Control Under-Voltage Lockout Thermal Shutdown kv ESD Rating UL Approved File No. E77 -Pin SOT or 8-Pin SC7JW Package Temperature Range: - C to +8 C Applications Hot Swap Supplies Notebook Computers Peripheral Ports Personal Communication Devices UL Recognized Component Typical Application INPUT IN AATB SOT- OUT OUTPUT ON (ON) ON/(ON) SET μf R SET.7μF B

2 AATB Pin Descriptions SOT- Pin Number SC7JW-8 Symbol Function OUT P-channel MOSFET drain. Connect a.7μf capacitor from OUT to., 7, 8 Ground connection. SET Current limit set input. A resistor from SET to ground sets the current limit for the switch. ON Enable input. Two versions are available, active-high and active-low. See Ordering Information for details., IN P-channel MOSFET source. Connect a μf capacitor from IN to. Pin Configuration SOT- (Top View) SC7JW-8 (Top View) OUT SET IN ON SET ON IN IN 8 7 OUT B.9.9..

3 AATB Absolute Maximum Ratings T A = C, unless otherwise noted. Symbol Description Value Units V IN IN to -. to V V ON ON(ON) to -. to V IN +. V V SET, V OUT SET, OUT to -. to V IN +. V I MAX Maximum Continuous Switch Current A T J Operating Junction Temperature Range - to C T LEAD Maximum Soldering Temperature (at Leads) C V ESD ESD Rating - HBM V Thermal Characteristics Symbol Description Value Units Θ JA Thermal Resistance (SOT- or SC7JW-8) C/W P D Power Dissipation (SOT- or SC7JW-8) 7 mw. 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.. Human body model is a pf capacitor discharged through a.kω resistor into each pin.. Mounted on a demo board. B

4 AATB Electrical Characteristics V IN = V, T A = - C to +8 C, unless otherwise noted. Typical values are T A = C. Symbol Description Conditions Min Typ Max Units V IN Operation Voltage.. V I Q Quiescent Current V IN = V, ON (ON) = Active, I OUT = 9 μa I Q(OFF) Off Supply Current ON (ON) = Inactive, V IN =.V μa I SD(OFF) Off Switch Current ON (ON) = Inactive, V IN =.V, V OUT =. μa V UVLO Under-Voltage Lockout Rising Edge, % Hysteresis.8. V V IN =.V, T A = C 8 R DS(ON) On Resistance V IN =.V, T A = C mω V IN =.V, T A = C 9 TC RDS On Resistance Temperature Coefficient 8 ppm/ C I LIM Current Limit R SET =.8kΩ... A I LIM(MIN) Minimum Current Limit ma V ON(L) ON (ON) Input Low Voltage V IN =.7V to.v.8 V V ON(H) ON (ON) Input High Voltage V IN =.7V to <.V. V IN.V to.v. V I ON(SINK) ON (ON) Input Leakage V ON =.V. μa T RESP Current Limit Response Time V IN = V. μs T OFF Turn-Off Time V IN = V, R L = Ω μs T ON Turn-On Time V IN = V, R L = Ω μs T SD Over-Temperature Threshold V IN = V T J Increasing T J Decreasing C. For V IN outside this range, consult Typical ON (ON) Threshold curve. B.9.9..

5 AATB Typical Characteristics Unless otherwise noted, V IN = V, T A = C. Quiescent Current vs. Temperature Quiescent Current vs. Input Voltage Quiescent Current (μa) Quiescent Current (μa) Input Voltage (V) Output Current vs. Output Voltage (R SET =.kω) R DS(ON) vs. Temperature Output Current (A) Output Voltage (V) R DS(ON) (mω) Input = V 8 Input = V Temperature ( C) Off-Supply Current vs. Temperature Off-Switch Current vs. Temperature Off-Supply Current (μa) Off-Switch Current (μa) B

6 AATB Typical Characteristics Unless otherwise noted, V IN = V, T A = C. Turn-On vs. Temperature (R LOAD = Ω; C LOAD =.7μF) Turn-Off vs. Temperature (R LOAD = Ω; C LOAD =.7μF) Turn-On Time (μs) V IN = V V IN = V Turn-Off Time (μs) V IN = V V IN = V Turn-On (R L = Ω; C L =.7μF) Turn-Off (R L = Ω; C L =.7μF) Voltage (V) ON Output Voltage (V) ON Output Time (μs) Time (μs) Short-Circuit Through.Ω V IH and V IL vs. V IN Input and Output Voltage (V) 8 7 Input Voltage 8 Output Current Output Voltage Time (μs) Output Current (A) V IH. V IL V IN (V) B.9.9..

7 AATB Typical Characteristics Unless otherwise noted, V IN = V, T A = C. R SET vs. I LIM R SET Coefficient vs. I LIM R SET (kω) R SET I LIM Product (kv) I LIM (ma) I LIM (A) Output Current vs. Temperature (R SET =.kω). Current Limit (%) B

8 AATB Functional Block Diagram IN OUT Under- Voltage Lockout Over-Temperature Protection ON (ON).V Reference Current Limit SET R SET Application Information Setting Current Limit In most applications, the variation in I LIM must be taken into account when determining R SET. The I LIM variation is due to processing variations from part to part, as well as variations in the voltages at IN and OUT, plus the operating temperature. See charts Current Limit vs. Temperature and Output Current vs. V OUT. Together, these three factors add up to a ±% tolerance (see I LIM specification in Electrical Characteristics section). Figure illustrates a cold device with a statistically higher current limit and a hot device with a statistically lower current limit, both with R SET equal to 8.87kΩ. While the chart, "R SET vs. I LIM indicates an I LIM of.a with an R SET of.kω, this figure shows that the actual current limit will be at least.8a and no greater than.7a. To determine R SET, start with the maximum current drawn by the load and multiply it by. (typical I LIM = minimum I LIM /.7). This is the typical current limit value. Next, refer to R SET vs. I LIM and find the R SET 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 R SET may also be calculated using the I LIM R SET product found in the chart R SET Coefficient vs. I LIM. The maximum current is derived by multiplying the typical current for the chosen R SET in the chart by.. A few standard resistor values are listed in Table. Current Limit (A) Current Limit vs. Output Voltage (R SET = 8.87kΩ) IMAX =.7A Device with high current limit at - C Device with low current limit at 8 C IMIN =.8A Output Voltage (V) Figure : Current Limit Using.kΩ. 8 B.9.9..

9 AATB R SET (kω) Current Limit Typ (ma) Device Will Not Current Limit Below (ma) Device Always Current Limits Below (ma) Table : Current Limit R SET Values Example: A USB port requires.a..a multiplied by. is.a. From the chart named R SET vs. I LIM, R SET should be less than 8kΩ. 7.8kΩ is a standard value that is a little less than 8kΩ but very close. The chart reads approximately.a as a typical I LIM value for 7.8kΩ. Multiplying.A by.7 and. shows that the AATB will limit the load current to greater than.9a but less than.a. Operation in Current Limit When a heavy load is applied to the output of the AATB, the load current is limited to the value of I LIM determined by R SET (see Figure ). Since the load is demanding more current than I LIM, the voltage at the output drops. This causes the AATB to dissipate a larger than normal quantity of power, and its die temperature to increase. When the die temperature exceeds an over-temperature limit, the AATB will shut down until is has cooled sufficiently, at which point it will startup again. The AATB 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. 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 of the AATB has low and high threshold voltages that accommodate this condition. The threshold voltages are compatible with V TTL and.v to V CMOS. Reverse Voltage The AATB 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 AATB. Overload Operation Output Voltage (V).7.. Output Current Ω load is turned on at time = Output Voltage Output Current (A) Figure : Overload Operation. B

10 AATB Ordering Information Package Enable Marking Part Number (Tape and Reel) SOT- ON (active high) 8FXYY AATBIGV--T SC7JW-8 ON (active high) 8GXYY AATBIJS--T SOT- ON (active low) B9XYY AATBIGV-T SC7JW-8 ON (active low) B8XYY AATBIJS-T 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.% by weight in homogeneous materials. For more information, please visit our website at Package Information SOT-.8 ±..9 BSC.9 BSC.7 ±..8 ±.. REF. ±.. ±.. ±.7 GAUGE PLANE ±. ±..7 ±.7 ±. REF. ±.. BSC All dimensions in millimeters.. XYY = assembly and date code.. Sample stock is generally held on part numbers listed in BOLD. B.9.9..

11 AATB SC7JW-8. BSC. BSC. BSC.7 ±.. ±.. ±.7. ±..8 ±.. MAX. ±... ±. 7 ± ±.8REF. ±.. ±. All dimensions in millimeters. Advanced Analogic Technologies, Inc. Scott Boulevard, Santa Clara, CA 9 Phone (8) 77- Fax (8) 77- 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. Except as provided in AnalogicTech s terms and conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. 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. B