AAT4280 AAT | Alldatasheet

Document overview

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Technical content

Features

  • 1.8V to 5.5V Input Voltage Range
  • Very Low R DS(ON), Typically 80mΩ (5V)
  • Slew Rate Limited Turn-On Time Options — 1ms — 0.5µs — 100µs
  • Fast Shutdown Load Discharge Option
  • Low Quiescent Current — 2.5µA Typical — 1µA Max in Shutdown
  • TTL/CMOS Input Logic Level
  • Temperature Range: -40ºC to +85°C
  • 4kV ESD Rating
  • 6-Pin SOT23 or 8-Pin SC70JW Package

Applications

  • Cellular Telephones
  • Digital Still Cameras
  • Hot Swap Supplies
  • Notebook Computers
  • Personal Communication Devices
  • Personal Digital Assistants (PDA) AAT4280 Slew Rate Controlled Load Switch Typical Application AAT4280 COUT 0.1μF CIN 1μF OUTIN GND VOUT GNDGND VIN ON/OFF GND IN ON 4280.2006.11.1.4 1

(Top View) SC70JW-8 (Top View) Selector Guide Slew Rate Active Part Number (typ) Pull Down Enable AAT4280-1 1ms Active High AAT4280-2 0.5µs Active High AAT4280-3 100µs √ Active High OUT ON/OFF GND IN IN IN IN IN 1 GND IN GND INON/OFF OUT 1 3 4 Pin # SOT23-6 SC70JW-8 Symbol Function 1 2 OUT This pin is the P-channel MOSFET drain connection. Bypass to ground through a 0.1µF capacitor. 2, 5 4 GND Ground connection. 3 3 ON/OFF Enable input. 4, 6 1, 5, 6, 7, 8 IN This pin is the input to the P-channel MOSFET source. Bypass to ground through a 1.0µF capacitor. AAT4280 Slew Rate Controlled Load Switch 2 4280.2006.11.1.4

TA = 25°C, unless otherwise noted. Thermal Characteristics3 Value Symbol Description SOT23-6 SC70JW-8 Units ΘJA Thermal Resistance 120 140 °C/W PD Power Dissipation 833 714 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 2.3 A IDM Maximum Pulsed Current IN ≥ 2.5V 6 A IN < 2.5V 3 A TJ Operating Junction Temperature Range -40 to 150 °C TS Storage Temperature Range -65 to 150 °C TLEAD Maximum Soldering Temperature (at leads) 300 °C VESD ESD Rating2 - HBM 4000 V AAT4280 Slew Rate Controlled Load Switch 4280.2006.11.1.4 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 AAT4280 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 AAT4280 All Versions VIN Operation Voltage 1.8 1 5.5 V VUVLO Under-Voltage Lockout V IN Falling 1.0 1.4 1.8 V VUVLO(hys) Under-Voltage Lockout Hysteresis 250 mV IQ Quiescent Current ON/OFF = Active 2.5 4 µA IQ(OFF) Off Supply Current ON/OFF = Inactive, OUT = Open 1 µA ISD(OFF) Off Switch Current ON/OFF = Inactive, V OUT = 0 1 µA VIN = 5V, TA = 25°C 80 120 RDS(ON) On Resistance VIN = 4.2V, TA = 25°C 85 130 mΩVIN = 3V, TA = 25°C 100 150 VIN = 1.8V, TA = 25°C 160 250 TCRDS On Resistance Temperature 2800 ppm/°CCoefficient VIL ON/OFF Input Logic Low Voltage V IN = 2.7V to 5.5V2 0.8 V VIN = 2.7V to ≤ 4.2V 2 VIH ON/OFF Input Logic High Voltage V IN = 3.3V 1.8 V VIN = >4.2V to 5.5V 2.4 ISINK ON/OFF Input Leakage V ON/OFF = 5.5V 1 µA AAT4280-1 TD(ON) Output Turn-On Delay V IN = 5V, RLOAD = 10Ω, TA = 25°C 20 40 µs TON Output Turn-On Rise Time V IN = 5V, RLOAD = 10Ω, TA = 25°C 1000 1500 µs TD(OFF) Output Turn-Off Delay Time V IN = 5V, RLOAD = 10Ω, TA = 25°C 4 10 µs AAT4280-2 TD(ON) Output Turn-On Delay V IN = 5V, RLOAD = 10Ω, TA = 25°C 0.5 2 µs TON Output Turn-On Rise Time V IN = 5V, RLOAD = 10Ω, TA = 25°C 0.5 1 µs TD(OFF) Output Turn-Off Delay Time V IN = 5V, RLOAD = 10Ω, TA = 25°C 4 10 µs AAT4280-3 TD(ON) Output Turn-On Delay V IN = 5V, RLOAD = 10Ω, TA = 25°C 20 40 µs TON Output Turn-On Rise Time V IN = 5V, RLOAD = 10Ω, TA = 25°C 100 150 µs TD(OFF) Output Turn-Off Delay Time V IN = 5V, RLOAD = 10Ω, TA = 25°C 4 10 µs RPD Output Pull-Down Resistance ON/OFF = Inactive, TA = 25°C 150 250 ΩDuring OFF AAT4280 Slew Rate Controlled Load Switch 4 4280.2006.11.1.4 1. Part requires minimum start-up of VIN ≥ 2.0V to ensure operation down to 1.8V. 2. For VIN outside this range, consult typical ON/OFF threshold curve.

Unless otherwise noted, VIN = 5V, TA = 25°C. Off-Switch Current vs. Temperature 0.001 0.010 0.100 1.000 -40 -20 0 20 40 60 80 100 Temperature (°C) IOFFSW (μA) ON/OFF Threshold vs. Input Voltage 0.4 0.60.8 1.0 1.2 1.41.6 1.8 2.02.2 Input Voltage (V) ON/OFF Threshold (V) VIH VIL RDS(ON) vs. Temperature 100 110 120 -40 -20 0 20 40 60 80 100 Temperature (°C) RDS(ON) (mΩ) VIN = 5V VIN = 3V RDS(ON) vs. Input Voltage 110 130 150 170 190 Input Voltage (V) RDS(ON) (mΩ) 500mA 100mA Quiescent Current vs. Input Voltage 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0123456 Input Voltage (V) Quiescent Current (μA) Quiescent Current vs. Temperature -40 -20 0 20 40 60 80 100 Temperature (°C) Quiescent Current (μA) VIN = 5V VIN = 3V AAT4280 Slew Rate Controlled Load Switch 4280.2006.11.1.4 5

Typical Characteristics—AAT4280-1 Unless otherwise noted, VIN = 5V, TA = 25°C. AAT4280-1 Turn-Off (VIN = 5V; RL = 10Ω) Time (10μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-1 Turn-Off (VIN = 3V; RL = 6Ω) Time (10μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-1 Turn-On (VIN = 5V; RL = 10Ω) Time (500μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-1 Turn-On (VIN = 3V; RL = 6Ω) Time (500μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280 Slew Rate Controlled Load Switch 6 4280.2006.11.1.4

Slew Rate Controlled Load Switch 4280.2006.11.1.4 7 Typical Characteristics—AAT4280-2 Unless otherwise noted, VIN = 5V, TA = 25°C. AAT4280-2 Turn-Off (VIN = 5V; RL = 10Ω) Time (5μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-2 Turn-Off (VIN = 3V; RL = 6Ω) Time (5μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-2 Turn-On (VIN = 5V; RL = 10Ω) Time (5μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-2 Turn-On (VIN = 3V; RL = 6Ω) Time (5μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div)

Typical Characteristics—AAT4280-3 Unless otherwise noted, VIN = 5V, TA = 25°C. AAT4280-3 Turn-Off (VIN = 5V; RL = 10Ω) Time (5μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-3 Turn-Off (VIN = 3V; RL = 6Ω) Time (5μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-3 Turn-On (VIN = 5V; RL = 10Ω) Time (50μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280-3 Turn-On (VIN = 3V; RL = 6Ω) Time (50μs/div) ON/OFF (5V/div) VOUT (2V/div) IIN (200mA/div) AAT4280 Slew Rate Controlled Load Switch 8 4280.2006.11.1.4

The AAT4280 is a family of flexible P-channel MOS- FET power switches designed for high-side load switching applications. There are three versions of the AAT4280 with different turn-on and turn-off char- acteristics to choose from, depending upon the spe- cific requirements of an application. The first ver- sion, the AAT4280-1, has a moderate turn-on slew rate feature, which reduces inrush current when the MOSFET is turned on. This function allows the load switch to be implemented with either a small input capacitor or no input capacitor at all. During turn-on slewing, the current ramps linearly until it reaches the level required for the output load condition. The proprietary turn-on current 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. The second version, the AAT4280-2, is a very fast switch intended for high-speed switching applica- tions. This version has no turn-on slew rate control and no special output discharge features. The final version, the AAT4280-3, has the addition of a minimized slew rate limited turn-on function and a shutdown output discharge circuit to rapidly turn off a load when the load switch is disabled through the ON/OFF pin. All versions of the AAT4280 operate with input volt- ages ranging from 1.8V to 5.5V. All versions of this device have extremely low operating current, mak- ing them ideal for battery-powered applications. In cases where the input voltage drops below 1.8V, the AAT4280 MOSFET device is protected from entering into the saturation region of operation by automatically shutting down through an under-volt- age lockout control circuit. The ON/OFF control pin is TTL compatible and will also function with 2.5V to 5V logic systems, making the AAT4280 an ideal level-shifting load switch. AAT4280 Slew Rate Controlled Load Switch 4280.2006.11.1.4 9 Functional Block Diagram Under- Voltage Lockout Level Shift IN ON/OFF OUT GND Turn-On Slew Rate Control *AAT4280-3 only

Slew Rate Controlled Load Switch 10 4280.2006.11.1.4 Applications Information Input Capacitor A 1µF or larger capacitor is typically recommended for CIN in most applications. A CIN capacitor is not required for basic operation. However, C IN is use- ful 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 capac- itors may be selected for C IN. There is no specific capacitor ESR requirement for C IN. However, for higher current operation, ceramic capacitors are recommended for C IN due to their inherent capabil- ity over tantalum capacitors to withstand input cur- rent surges from low impedance sources, such as batteries in portable devices. Output Capacitor For proper slew operation, a 0.1µF capacitor or greater between V OUT and GND is recommended. The output capacitor has no specific capacitor type or ESR requirement. If desired, C OUT may be increased without limit to accommodate any load transient condition without adversely affecting the device turn-on slew rate time. Enable Function The AAT4280 features an enable / disable function. This pin (ON/OFF) is compatible with both TTL or CMOS logic. 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, main- taining a reverse bias on the internal parasitic diode. Conditions where V OUT might exceed V IN should be avoided since this would forward bias the internal parasitic diode and allow excessive current flow into the V OUT pin and possibly damage the load switch. In applications where there is a possibility of V OUT exceeding VIN for brief periods of time during normal operation, the use of a larger value CIN capacitor is highly recommended. A larger value of C IN with respect to COUT 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 AAT4280 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 need to be taken into account. The following discussions will assume the load switch is mounted on a printed circuit board utiliz- ing the minimum recommended footprint, as stated in the Layout Considerations 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: P D(MAX) = [TJ(MAX) - TA] / ΘJA Constants for the AAT4280 are maximum junction temperature, TJ(MAX) = 125°C, and package thermal resistance, ΘJA = 120°C/W. Worst case conditions are calculated at the maximum operating tempera- ture where 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) = 333mW. At TA = 25°C, PD(MAX) = 833mW. The maximum continuous output current for the AAT4280 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 temperature R DS by the R DS temperature coefficient. The tem- perature coefficient (TC) is 2800ppm/°C. Therefore, MAX RDS125°C = RDS25°C · (1 + TC · ΔT) MAX RDS125°C = 120mΩ · (1 + 0.0028 ·

Slew Rate Controlled Load Switch 4280.2006.11.1.4 11 For maximum current, refer to the following equation: IOUT(MAX) < ( PD(MAX) / RDS)1/2 For example, if VIN = 5V, RDS(MAX) = 154mΩ and TA = 25°C, IOUT(MAX) = 2.3A. If the output load current were to exceed 2.3A 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 AAT4280. 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. 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. 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 in the additional power dissipation due to the short duration, high-current peak scaled by the duty factor. For example, a 4V system using an AAT4280 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 calculated approximately by consulting the chart of R DS(ON) vs. VIN. The RDS reported for 5V can be scaled by the ratio seen in the chart to derive the R DS for a 4V V IN: 120mΩ · 87mΩ /80mΩ = 130mΩ. De-rated for temperature: The power dissipation for a 100mA load is calculat- ed as follows: P D(MAX) = IOUT 2 · RDS PD(100mA) = (100mA)2 · 166mΩ PD(100mA) = 1.66mW PD(87.5%D/C) = %DC · PD(100mA) PD(87.5%D/C) = 1.45mW The power dissipation for 100mA load at 87.5% duty cycle is 1.45mW. Now the power dissipation for the remaining 12.5% of the duty cycle at 2A is calculated: P D(MAX) = IOUT 2 · RDS PD(2A) = (2A)2 · 166mΩ PD(2A) = 664mW PD(12.5%D/C) = %DC · PD(2A) PD(12.5%D/C) = 83mW The power dissipation for 2A load at 12.5% duty cycle is 83mW. 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) = 1.45mW + 83mW PD(total) = 84.5mW The maximum power dissipation for the AAT4280 operating at an ambient temperature of 85°C is 333mW. The device in this example will have a total power dissipation of 84.5mW. This is well within the thermal limits for safe operation of the device; in fact, at 85°C, the AAT4280 will handle a 2A pulse for up to 50% duty cycle. At lower ambi- ent temperatures, the duty cycle can be further increased.

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. AAT4280 Slew Rate Controlled Load Switch 12 4280.2006.11.1.4 Printed Circuit Board Layout Recommendations For proper thermal management and to take advantage of the low RDS(ON) of the AAT4280, 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. To maximize package thermal dispation and power handling capacity of the AAT4280 SOT23-6/ SC70JW-8 package, the ground plane area con- nected to the ground pins should be made as large as possible. For best performance, C IN and COUT should be placed close to the package pins. Evaluation Board Layout The AAT4280 evaluation layout follows the printed circuit board layout recommendations, and can be used for good applications layout. Refer to Figures 1 through 3. Note: Board layout shown is not to scale.

Ordering Information

Package Information

All dimensions in millimeters.

1.90 BSC

0.95 BSC

0.45 ± 0.15 0.10 BSC 2.85 ± 0.15 0.075 ± 0.075 0.40 ± 0.10 × 6 1.575 ± 0.125 1.20 ± 0.25 1.10 ± 0.20 2.80 ± 0.20 4° ± 4° 10° ± 5° 0.15 ± 0.07 GAUGE PLANE

0.60 REF

All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means Device Option Package Marking 1 Part Number (Tape and Reel)2 AAT4280-1 SOT23-6 COXYY AAT4280IGU-1-T1 AAT4280-2 SOT23-6 BZXYY AAT4280IGU-2-T1 AAT4280-3 SOT23-6 CJXYY AAT4280IGU-3-T1 AAT4280-1 SC70JW-8 COXYY AAT4280IJS-1-T1 AAT4280-2 SC70JW-8 BZXYY AAT4280IJS-2-T1 AAT4280-3 SC70JW-8 CJXYY AAT4280IJS-3-T1 AAT4280 Slew Rate Controlled Load Switch 4280.2006.11.1.4 13 1. XYY = assembly and date code. 2. Sample stock is generally held on all part numbers listed in BOLD.

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 AAT4280 Slew Rate Controlled Load Switch 14 4280.2006.11.1.4 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 sub- ject 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. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and produ ct names appearing in this document are regis- tered trademarks or trademarks of their respective holders.