AAT4250

AAT4250 AAT | Alldatasheet

Document overview

• Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
• PDF pages: 13

Technical content

Features

• 1.8V to 5.5V Input Voltage Range
• 120m Ω (5V) Typical R DS(ON)
• Low Quiescent Current:
• Typical 2µA
• Typical 0.1µA with Enable Off
• Only 2.0V Needed for ON/OFF Control
• Temperature Range: -40°C to +85°C
• 5kV ESD Rating
• SOT23-5 or SC70JW-8 Package

Applications

• Hot Swap Supplies
• Notebook Computers
• Personal Communication Devices AAT4250 Slew Rate Controlled Load Switch Typical Application AAT4250 ON/OFF IN OUT GND ON 1µF 0.1µF INPUT GND GND CIN COUT OUTPUT 4250.2006.03.1.3 1

SOT23-5 (SOT25) (Top View) SC70JW-8 (Top View) GND GND GND IN IN ON/OFF GND OUT 1 GND IN ON/OFFN/C OUT 1 3 4 Pin # SOT23-5 SC70JW-8 Symbol Function 1 1 OUT P-channel MOSFET drain. 2 2, 3, 4, 5 GND Ground connection. 3 N/A N/C Not internally connected. 4 6 ON/OFF Active-high enable input. Logic high turns the switch on. 5 7, 8 IN P-channel MOSFET source. AAT4250 Slew Rate Controlled Load Switch 2 4250.2006.03.1.3

TA = 25°C, unless otherwise noted. Thermal Characteristics3 Symbol Description Value Units ΘJA Thermal Resistance 150 °C/W PD Power Dissipation 667 mW Symbol Description Value Units VIN IN to GND -0.3 to 6 V VON ON/OFF to GND -0.3 to 6 V VOUT OUT to GND -0.3 to V IN + 0.3 V IMAX Maximum Continuous Switch Current 1.7 A IDM Maximum Pulsed Current IN ≥ 2.5V 4 AIN < 2.5V 2 TJ Operating Junction Temperature Range -40 to 150 °C TLEAD Maximum Soldering Temperature (at leads) 300 °C VESD ESD Rating2 - HBM 5000 V AAT4250 Slew Rate Controlled Load Switch 4250.2006.03.1.3 3 1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi- tions 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 1.5k Ω resistor into each pin. 3. Mounted on an AAT4250 demo board in still 25ºC air.

Electrical Characteristics

VIN = 5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are T A = 25°C. Symbol Description Conditions Min Typ Max Units VIN Operation Voltage 1.8 1 5.5 V IQ Quiescent Current V IN = 5V, ON/OFF = VIN, IOUT = 0 2 4 µA IQ(OFF) Off Supply Current ON/OFF = GND, V IN = 5V, OUT Open 1 µA ISD(OFF) Off Switch Current ON/OFF = GND, V IN = 5V, VOUT = 0 0.1 1 µA VUVLO Under-Voltage Lockout V IN Falling 1.0 1.5 1.8 V VUVLO(hys) Under-Voltage Lockout 250 mVHysteresis VIN = 5V, TA = 25°C 120 175 RDS(ON) On Resistance V IN = 3V, TA = 25°C 135 200 m Ω VIN = 1.8V 165 TCRDS On Resistance Temperature 2800 ppm/°CCoefficient VIL ON/OFF Input Logic VIN = 2.7V to 5.5V2 0.8 VLow Voltage VIH ISINK ON Input Leakage V ON = 5V 0.01 1 µA TD Output Turn-On Delay Time 300 µs TDOFF Turn-Off Delay Time VIN = 5V, RLOAD = 10Ω 10 µsVIN = 3V, RLOAD = 5Ω 10 VIN = 5V, RLOAD = 16.5Ω, TA = 0 to 50°C 1000 TON Turn-On Rise Time V IN = 5V, RLOAD = 10Ω, COUT = 0.1µF 1500 µs VIN = 3V, RLOAD = 5Ω, COUT = 0.1µF 1500 AAT4250 Slew Rate Controlled Load Switch 4 4250.2006.03.1.3 1. Part requires minimum start-up of V IN ≥ 2.0V to ensure operation down to 1.8V. 2. For VIN outside this range, consult typical ON/OFF threshold curve.

Slew Rate Controlled Load Switch 4250.2006.03.1.3 5 Typical Characteristics Unless otherwise noted, VIN = 5V, TA = 25°C. Turn-On Time vs. Temperature (CIN = 1µF; COUT = 0.1µF) 0.5 1.0 1.5 2.0 2.5 3.0 -40 -20 0 20 40 60 80 100 Temperature (°C) Turn-On Time (ms) VIN = 5V RLOAD = 10ΩVIN = 3V RLOAD = 5Ω Turn-Off Time vs. Temperature (CIN = 1µF; COUT = 0.1µF) -40 -20 0 20 40 60 80 100 Temperature (°C) Turn-Off Time (µs) VIN = 5V RLOAD = 10Ω VIN = 3V RLOAD = 5Ω Off-Switch Current vs. Temperature 100 1000 10000 -40 -20 0 20 40 60 80 100 Temperature (°C) Off-Switch Current (nA) Off-Supply Current vs. Temperature 100 1000 -40 -20 0 20 40 60 80 100 Temperature (°C) Off-Supply Current (nA) Quiescent Current vs. Input Voltage 0.5 1.5 2.5 3.5 0123456 Quiescent Current (µA) Input Voltage (V) Quiescent Current vs. Temperature 0.5 1.5 2.5 3.5 -40 -20 0 20 40 60 80 100 Temperature (°C) Quiescent Current (µA) VIN = 3V VIN = 5V

Slew Rate Controlled Load Switch 6 4250.2006.03.1.3 Typical Characteristics Unless otherwise noted, VIN = 5V, TA = 25°C. Turn-Off Waveforms (CIN = 1µF; COUT = 1µF; VIN = 5V) Time (µs) -1 1 3 5 7 9 11 13 15 VOUT Voltage (V) V(ON/OFF)0 Turn-Off Waveforms (CIN = 1µF; COUT = 1µF; VIN = 3V) Time (µs) -1 1 3 5 7 9 11 13 15 VOUT Voltage (V)V(ON/OFF) -1 0 1 2 3 4 1.2 Time (ms) Turn-On Waveforms (CIN = 1µF; COUT = 10µF; VIN = 5V) VOUT 0.8 0.6 0.4 0.2 IIN Voltage (V) Current (A) V(ON/OFF) Voltage (V) -1 0 1 2 3 4 0.5 1.5 Time (ms) Turn-On Waveforms (CIN = 1µF; COUT = 10µF; VIN = 3V) VOUT Current (A) V(ON/OFF) IIN Voltage (V) -1 0 1 2 3 4 1.2 Time (ms) Turn-On Waveforms (CIN = 1µF; COUT = 0.1µF; VIN = 5V) VOUT 0.8 0.6 0.4 0.2 IIN Current (A) V(ON/OFF) Voltage (V) -1 0 1 2 3 4 0.5 1.5 Time (ms) Turn-On Waveforms (CIN = 1µF; COUT = 0.1µF; VIN = 3V) V(ON/OFF) VOUT IIN Current (A)

Slew Rate Controlled Load Switch 4250.2006.03.1.3 7 Typical Characteristics Unless otherwise noted, VIN = 5V, TA = 25°C. Typical ON/OFF Threshold vs. Input Voltage 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 Input Voltage (V) ON/OFF Threshold VIH VIL RDS(ON) vs. Input Voltage 110 120 130 140 150 160 170 180 190 Input Voltage (V) RDS(ON) (mΩ) IOUT = 100mA RDS(ON) vs. Temperature 120 110 100 150 140 130 160 -40 -20 0 20 40 60 80 100 Temperature (°C) RDS(ON) (mΩ) VIN = 3V VIN = 5V

Slew Rate Controlled Load Switch 8 4250.2006.03.1.3 Functional Description The AAT4250 is a slew rate controlled P-channel MOSFET power switch designed for high-side load switching applications. It operates with input volt- ages ranging from 1.8V to 5.5V which, along with its extremely low operating current, makes it ideal for battery-powered applications. In cases where the input voltage drops below 1.8V, the AAT4250 MOS- FET is protected from entering the saturated region of operation by automatically shutting down. In addition, the TTL compatible ON/OFF pin makes the AAT4250 an ideal level-shifted load switch. The slew rate controlling feature eliminates inrush cur- rent when the MOSFET is turned on, allowing the AAT4250 to be used with a small input capacitor, or no input capacitor at all. During slewing, the current ramps linearly until it reaches the level required for the output load condition. The proprietary control method works by careful control and monitoring of the MOSFET gate voltage. When the device is switched ON, the gate voltage is quickly increased to the threshold level of the MOSFET. Once at this level, the current begins to slew as the gate voltage is slowly increased until the MOSFET becomes fully enhanced. Once it has reached this point, the gate is quickly increased to the full input voltage and R DS(ON) is minimized. Applications Information Input Capacitor A 1µF or larger capacitor is typically recommended for C IN in most applications. A CIN capacitor is not required for basic operation; however, it is useful in preventing load transients from affecting upstream circuits. C IN should be located as close to the device V IN pin as practically possible. Ceramic, tantalum, or aluminum electrolytic capacitors may be selected for C IN. There is no specific capacitor equivalent series resistance (ESR) requirement for C IN. However, for higher current operation, ceram- ic capacitors are recommended for CIN due to their inherent capability over tantalum capacitors to with- stand input current surges from low-impedance sources, such as batteries in portable devices. Output Capacitor For proper slew operation, a 0.1µF capacitor or greater is required between V OUT and GND. Likewise, with the output capacitor, there is no spe- cific capacitor ESR requirement. If desired, C OUT may be increased without limit to accommodate any load transient condition without adversely affecting the slew rate. Functional Block Diagram Under- Voltage Lockout Level Shift Slew Rate Control IN ON/OFF GND OUT

The AAT4250 features an enable / disable function. This pin (ON) is active high and is compatible with TTL or CMOS logic. To assure the load switch will turn on, the ON control level must be greater than 2.0V. The load switch will go into shutdown mode when the voltage on the ON pin falls below 0.8V. When the load switch is in shutdown mode, the OUT pin is tri-stated, and quiescent current drops to leakage levels below 1µA. Reverse Output-to-Input Voltage Conditions and Protection Under normal operating conditions, a parasitic diode exists between the output and input of the load switch. The input voltage should always remain greater than the output load voltage, maintaining a reverse bias on the internal parasitic diode. Conditions where V OUT might exceed VIN should be avoided since this would forward bias the internal parasitic diode and allow excessive current flow into the V OUT pin, possibly damaging the load switch. In applications where there is a possibility of V OUT exceeding VIN for brief periods of time during nor- mal operation, the use of a larger value CIN capaci- tor is highly recommended. A larger value of C IN with respect to C OUT will effect a slower C IN decay rate during shutdown, thus preventing V OUT from exceeding V IN. In applications where there is a greater danger of VOUT exceeding VIN for extended periods of time, it is recommended to place a Schottky diode from V IN to V OUT (connecting the cathode to VIN and anode to V OUT). The Schottky diode forward voltage should be less than 0.45V. Thermal Considerations and High Output Current Applications The AAT4250 is designed to deliver a continuous output load current. The limiting characteristic for maximum safe operating output load current is package power dissipation. In order to obtain high operating currents, careful device layout and circuit operating conditions must be taken into account. The following discussions will assume the load switch is mounted on a printed circuit board utilizing the minimum recommended footprint as stated in the Printed Circuit Board Layout Recommendations section of this datasheet. At any given ambient temperature (T A), the maxi- mum package power dissipation can be deter- mined by the following equation: Constants for the AAT4250 are maximum junction temperature (T J(MAX) = 125°C) and package ther- mal resistance (ΘJA = 150°C/W). Worst case con- ditions are calculated at the maximum operating temperature, T A = 85°C. Typical conditions are cal- culated under normal ambient conditions where TA = 25°C. At T A = 85°C, P D(MAX) = 267mW. At TA = 25°C, PD(MAX) = 667mW. The maximum continuous output current for the AAT4250 is a function of the package power dissi- pation and the R DS of the MOSFET at TJ(MAX). The maximum RDS of the MOSFET at T J(MAX) is calcu- lated by increasing the maximum room tempera- ture R DS by the R DS temperature coefficient. The temperature coefficient (TC) is 2800ppm/°C. Therefore, at 125°C: R DS(MAX) = RDS(25°C) × (1 + TC × ∆T) RDS(MAX) = 224mΩ For maximum current, refer to the following equation: For example, if VIN = 5V, RDS(MAX) = 224mΩ, and TA = 25°C, IOUT(MAX) = 1.7A. If the output load current were to exceed 1.7A or if the ambient temperature were to increase, the internal die temperature would increase and the device would be damaged. Higher peak currents can be obtained with the AAT4250. To accomplish this, the device thermal resistance must be reduced by increasing the heat sink area or by operating the load switch in a duty- cycle manner. Duty cycles with peaks less than 2ms in duration can be considered using the method below. IOUT(MAX) < PD(MAX) RDS 2⎛⎞ PD(MAX) = TJ(MAX) - TA θJA AAT4250 Slew Rate Controlled Load Switch 4250.2006.03.1.3 9

Slew Rate Controlled Load Switch 10 4250.2006.03.1.3 High Peak Output Current Applications Some applications require the load switch to oper- ate at a continuous nominal current level with short duration, high-current peaks. Refer to the I DM specification in the Absolute Maximum Ratings table to ensure the AAT4250’s maximum pulsed current rating is not exceeded. The duty cycle for both output current levels must be taken into account. To do so, first calculate the power dissi- pation at the nominal continuous current level, and then add the additional power dissipation due to the short duration, high-current peak scaled by the duty factor. For example, a 4V system using an AAT4250 oper- ates at a continuous 100mA load current level and has short 2A current peaks, as in a GSM applica- tion. The current peak occurs for 576µs out of a 4.61ms period. First, the current duty cycle is calculated: % Peak Duty Cycle: X/100 = 576µs/4.61ms % Peak Duty Cycle = 12.5% The load current is 100mA for 87.5% of the 4.61ms period and 2A for 12.5% of the period. Since the Electrical Characteristics do not report R DS(MAX) for 4V operation, it must be approximated by consulting the chart of R DS(ON) vs. VIN. The RDS reported for 5V RDS can be scaled by the ratio seen in the chart to derive the RDS for 4V VIN: 175mΩ x 120mΩ/115mΩ = 183mΩ. Derated for temperature: 183mΩ x (1 + 0.002800 x (125°C -25°C)) = 235m Ω. The power dissipation for a 100mA load is calculated as follows: PD(MAX) = I2 OUT x RDS PD(100mA) = (100mA)2 x 235mΩ PD(100mA) = 2.35mW PD(87.5%D/C) = %DC x PD(100mA) PD(87.5%D/C) = 2.1mW The power dissipation for 100mA load at 87.5% duty cycle is 2.1mW. Now the power dissipation for the remaining 12.5% of the duty cycle at 2A is cal- culated: P D(MAX) = I2 OUT x RDS PD(2A) = (2A)2 x 235mΩ PD(2A) = 940mW PD(12.5%D/C) = %DC x PD(2A) PD(12.5%D/C) = 0.125 x 940mW PD(12.5%D/C) = 117.5mW The power dissipation for 2A load at 12.5% duty cycle is 117mW. Finally, the two power figures are summed to determine the total true power dissipa- tion under the varied load. P D(total) = PD(100mA) + PD(2A) PD(total) = 2.1mW + 117.5mW PD(total) = 120mW The maximum power dissipation for the AAT4250 operating at an ambient temperature of 85°C is 267mW. The device in this example will have a total power dissipation of 120mW. This is well within the thermal limits for safe operation of the device; in fact, at 85°C, the AAT4250 will handle a 2A pulse for up to 28% duty cycle. At lower ambient temperatures, the duty cycle can be further increased. Printed Circuit Board Layout Recommendations For proper thermal management, and to take advantage of the low RDS(ON) of the AAT4250, a few circuit board layout rules should be followed: V IN and VOUT should be routed using wider than normal traces, and GND should be connected to a ground plane. For best performance, C IN and COUT should be placed close to the package pins.

Slew Rate Controlled Load Switch 4250.2006.03.1.3 11 Figure 1: Evaluation Board Figure 2: Evaluation Board Figure 3: Evaluation Board Top Side Silk Screen Layout / Component Side Layout. Solder Side Layout. Assembly Drawing. Evaluation Board Layout The AAT4250 evaluation layout follows the printed circuit board layout recommendations, and can be used for good applications layout. Note: Board layout shown is not to scale.

Slew Rate Controlled Load Switch 12 4250.2006.03.1.3

Ordering Information

Package Information

SOT23-5 (SOT25) All dimensions in millimeters. 4° ± 4° 0.15 ± 0.07 0.45 ± 0.15 0.10 BSC 1.20 ± 0.25 1.575 ± 0.125 2.80 ± 0.20 0.40 ± 0.10 0.60 REF 2.85 ± 0.15

1.90 BSC

0.95 BSC 1.10 ± 0.20 10° ± 5° GAUGE PLANE 0.075 ± 0.075

0.60 REF

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 Marking 1 Part Number (Tape and Reel)2 SOT23-5 (SOT25) ACXYY AAT4250IGV-T1 SC70JW-8 ACXYY AAT4250IJS-T1 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD.

Slew Rate Controlled Load Switch 4250.2006.03.1.3 13 SC70JW-8 All dimensions in millimeters. 0.225 ± 0.075 0.45 ± 0.10 0.05 ± 0.05 2.10 ± 0.30 2.00 ± 0.20 7° ± 3° 4° ± 4° 0.15 ± 0.05

1.10 MAX

0.100 2.20 ± 0.20 0.048REF 0.50 BSC 0.50 BSC 0.50 BSC Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 © 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 con- trol 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.