AAT4608 ANALOGICTECH

Document overview

  • Manufacturer or author: Provided By www.digicamel.com(FREE DATASHEET DOWNLOAD SITE)
  • PDF pages: 10

Technical content

Features

  • 2.7V to 5.5V Input voltage range
  • Programmable over current threshold
  • Fast transient response:
  • <1µs response to short circuit
  • Low quiescent current
  • 15µAtypical
  • 1µAmax with Switch off
  • 160mΩ typical R DS(ON)
  • Undervoltage Lockout
  • Thermal shutdown
  • Temp range -40 to 85°C
  • 4kV ESDRating
  • 5 pin SOT-23 package

Applications

  • Peripheral ports
  • Notebook computers
  • Personal communication devices
  • Hot swap supplies AAT4608 Current Limited Load Switch in SOT-23 Package Typical Application AAT4608 IN SET INPUT GND GND GND OUT SOT-23 OUTPUT 0.47µFRSET1µF Preliminary Information 4608.2001.10.0.9 1

Current Limited Load Switch in SOT-23 Package 2 4608.2001.10.0.9 Pin Configuration 5-Pin SOT-23 (Top View) Pin Descriptions Pin # Symbol Function 1 OUT P-channel MOSFETdrain. Connect 0.47µF capacitor from OUTto GND.

2 GND Ground connection

3 SET Current-Limit Set Input. Aresistor from SETto ground sets the current limit for the switch. 4 NC No internal connection. 5 IN P-channel MOSFETsource. Connect 1µF capacitor from IN to GND.

3 SET

Current Limited Load Switch in SOT-23 Package 4608.2001.10.0.9 3 Absolute Maximum Ratings (TA=25°C unless otherwise noted) Note: Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at con- ditions other than the operating conditions specified is not implied. Only one Absolute Maximum rating should be applied at any one time. Note 1: Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. Thermal Characteristics Note 2: Mounted on a demo board. Electrical Characteristics (VIN = 5V, TA = -40 to 85°C unless otherwise noted. Typical values are at TA=25°C) Symbol Description Conditions Min Typ Max Units VIN Operation Voltage 2.7 5.5 V IQ Quiescent Current V IN = 5V, IOUT = 0 15 30 µA VUVLO Undervoltage Lockout Rising edge, 1% hysteresis, 2.0 2.3 2.7 V VIN=5.0V 160 180 m Ω RDS(ON) On-Resistance V IN=4.5V 165 m Ω VIN=3.0V 195 230 m Ω ILIM Current Limit RSET = 6.8kΩ 0.5 1 2.0 A ILIM(MIN) Minimum Current Limit 150 mA TRESP Current Limit Response Time V IN=5V 0.8 µs Symbol Description Value Units ΘJA Thermal Resistance2 150 °C/W PD Power Dissipation2 667 mW Symbol Description Value Units VIN IN to GND -0.3 to 6 V VSET,VOUT SET, OUTto GND -0.3 to V IN+0.3 V IMAX Maximum Continuous Switch Current 2 A TJ Operating Junction Temperature Range -40 to 150 °C TLEAD Maximum Soldering Temperature (at Leads) 300 °C VESD ESDRating1 - HBM 4000 V

(Unless otherwise noted, VIN = 5V, TA = 25°C) Short Circuit through 0.6Ω 0123 Time (µs) Input and Output Output (A) Output Current InputVoltage Output Voltage (V) Short Circuit through 0.3Ω 0123 Time (µs) Input and Output Output (A) Output Current InputVoltage Output Voltage (V) RDS(ON) vs. Temperature 100 150 200 250 -40 -20 0 20 40 60 80 100 Te RDS(ON) (mΩ ) mperature (C) Input=3V Input=5V Output Current vsVOUT 0.2 0.4 0.6 012345 Vout (V) Output Current (A) RSET=16kΩ Quiescent Current 2.5 3 3.5 4 4.5 5 5.5 Input ( V ) Input ( µ A ) Quiescent Current vs. Temperature -40 -20 0 20 40 60 80 100 120 Temperature Quiescent Current (µA) (C) AAT4608 Current Limited Load Switch in SOT-23 Package 4 4608.2001.10.0.9

(Unless otherwise noted, VIN = 5V, TA = 25°C) Current Limit v. Temperature -6% -4% -2% -50 -25 0 25 50 75 100 Temperature (C) Current Limit (%) RSET=22.1k VIN-VOUT=0.5V RSET coefficent vsILIM 0 0.5 1 1.5 2 ILIM(A) RSET ILIM Product (kV) RSET vsILIM 100 0.1 10 1 ILIM(A) RSET (kΩ ) AAT4608 Current Limited Load Switch in SOT-23 Package 4608.2001.10.0.9 5

1.2V Reference Under- voltage Lockout Over-Temp Protection OUT SET GND RSET IN AAT4608 Current Limited Load Switch in SOT-23 Package 6 4608.2001.10.0.9

Current Limited Load Switch in SOT-23 Package 4608.2001.10.0.9 7 Applications Information Setting Current Limit In most applications, the variation in I LIM 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 3), plus the operating temper- ature. See charts "Current Limit vs. Temperature", and "Output Current vs. V OUT". Together these three factors add up to a ±25% tolerance (see I LIM specification in Electrical Characteristics section). In the figure below, a cold device with a statistical- ly higher current limit, and a hot device with a sta- tistically lower current limit, both with R SET equal to 10.5kΩ are shown. While the chart, "R SET vs. ILIM" indicates an ILIM of 0.7A with an R SET of 10.5kΩ , this figure shows that the actual current limit will be at least 0.525A, and no greater than 0.880A. To determine R SET,start with the maximum current drawn by the load, and multiply it by 1.33. (typi- cal_I LIM = 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 "R SET coeffi- cient vs. ILIM". The maximum current is derived by multiplying the typical current for the chosen R SET in the chart by 1.25. Afew standard resistor values are listed in the table "Current Limit R SET Values". Current Limit RSET Values Example: AUSB port requires 0.5A. 0.5Amultiplied by 1.33 is 0.665A. From the chart named "R SET vs. ILIM", RSET should be less than 11kΩ. 10.5 kΩ is a standard value that is a little less than 11k Ω but very close. The chart reads approximately 0.700A as a typical I LIM value for 10.5k Ω. Multiplying 0.700A by 0.75 and 1.25 shows that the AAT4608 will limit the load current to greater than 0.525Abut less than 0.875A. RSET Current Device will Device always (kΩ ) Limit typ not current current limits (mA) limit below: below: (mA) (mA) 40.2 200 150 250 30.9 250 188 313 24.9 300 225 375 22.1 350 263 438 19.6 400 300 500 17.8 450 338 563 16.2 500 375 625 14.7 550 413 688 13.0 600 450 750 10.5 700 525 875 8.87 800 600 1000 7.50 900 675 1125 6.81 1000 750 1250 6.04 1100 825 1375 5.49 1200 900 1500 4.99 1300 975 1625 4.64 1400 1050 1750 Current LimitUsing10.5kΩ 0.2 0.4 0.6 0.8 1.2 012345 VOUT (V) ILIM (A) 0.88A 0.525A Device with high current limit at -40°C Device with low current limit at 85°C

Operation in Current Limit When a heavy load is applied to the output of the AAT4608, the load current is limited to the value of I LIM determined by RSET. See the figure "Overload Operation". Since the load is demanding more cur- rent than I LIM, the voltage at the output drops. This causes the AAT4608 to dissipate a larger than nor- mal quantity of power, and its die temperature to increase. When the die temperature exceeds an over temperature limit, the AAT4608 will shut down until is has cooled sufficiently, at which point it will startup again. The AAT4608 will continue to cycle on and off until the load is removed or power is removed. Reverse Voltage The AAT4608 is designed to control current flowing from IN to OUT. If a voltage is applied to OUTwhich is greater than the voltage on IN, large currents may flow. This could cause damage to the AAT4608. AAT4608 Current Limited Load Switch in SOT-23 Package 8 4608.2001.10.0.9 Overload Operation Time ( s ) Output ( V) 0.25 0.5 0.75 Output (A) OutputCurrent OutputVoltage 1Ω loadis turnedonattime=0

Current Limited Load Switch in SOT-23 Package 4608.2001.10.0.9 9

Ordering Information

Package Information

E A c b D e L I H S Package Marking Part Number Bulk Tape and Reel SOT-23-5 N/A AAT4608IGV-T1 SOT-23-5 N/A AAT4608IGV-1-T1 Dim Millimeters Inches Min Max Min Max A 0.95 1.45 0.037 0.057 A1 0.05 0.15 0.002 0.006 A2 0.90 1.30 0.035 0.051 b 0.35 0.50 0.014 0.019 c 0.08 0.20 0.003 0.078 D 2.84 3.00 0.112 0.112 E1.50 1.70 0.059 0.067 e 1.90 0.0748 H 2.60 3.00 0.102 0.118 L 0.35 0.55 .0137 .0216 S 0.47 0.55 0.019 .0216 S1 .95 0.037 Θ 0° 10° 0° 10°

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