Datasheet AAT4280IGU-1-T1 Datasheet (Analogic) [ru]

Page 1

SmartSwitch

™

General Description

The AAT4280 SmartSwitch is a P-channel MOSFET power switch designed for high-side load switching applications. The P-channel MOSFET device has a typical R

DS(ON)

of 80mΩ, allowing increased load

switch power handling capacity. This device is available in three different versions with flexible turn on and off characteristics from very fast to slew rate limited. The standard AAT4280 (-1) version has a slew rate limited turn on load switch and is functionally compatible with the AAT4250 device while offering superior R

DS(ON)

characteristics. The AAT4280 (-2) version features fast load switch turn on capabilities, typically less than 500ns turn on and 3µs turn off times. The AAT4280 (-3) variation offers a shutdown load discharge circuit to rapidly turn off a load circuit when the switch is disabled. All AAT4280 load switch versions operate with an input voltage ranging from

1.8V to 5.5V, making them ideal for both 3V and 5V systems. The AAT4280 also features an under-voltage lockout which turns the switch off when an input under-voltage condition exists. Input logic levels are TTL and 2.5V to 5V CMOS compatible. The quiescent supply current is very low, typically 2.5µA. In shutdown mode, the supply current decreases to less than 1µA.

The AAT4280 is available in a Pb-free, 6-pin SOT23 or 8-pin SC70JW package and is specified over the -40°C to +85°C temperature range.

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

OUT

0.1μF

1μF

OUTIN

GND

OUT

GND

ON/OFF

GND

4280.2006.11.1.4 1

Page 2

Pin Descriptions

Pin Configuration

SOT23-6

(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

GND

ON/OFF

OUT

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

Page 3

Absolute Maximum Ratings

TA= 25°C, unless otherwise noted.

Thermal Characteristics

Value

Symbol Description

SOT23-6 SC70JW-8

Units

Thermal Resistance 120 140 °C/W

Power Dissipation 833 714 mW

Symbol Description Value Units

IN to GND -0.3 to 6 V

ON/OFF to GND -0.3 to 6 V

OUT

OUT to GND -0.3 to VIN+ 0.3 V

MAX

Maximum Continuous Switch Current 2.3 A

Maximum Pulsed Current

IN ≥ 2.5V 6 A IN < 2.5V 3 A

Operating Junction Temperature Range -40 to 150 °C

Storage Temperature Range -65 to 150 °C

LEAD

Maximum Soldering Temperature (at leads) 300 °C

ESD

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 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 an AAT4280 demo board in still 25ºC air.

Page 4

Electrical Characteristics

VIN= 5V, TA= -40°C to +85°C, unless otherwise noted. Typical values are TA= 25°C.

Symbol Description Conditions Min Typ Max Units

AAT4280 All Versions

Operation Voltage 1.8

5.5 V

UVLO

Under-Voltage Lockout VINFalling 1.0 1.4 1.8 V

UVLO(hys)

Under-Voltage Lockout Hysteresis 250 mV

Quiescent Current ON/OFF = Active 2.5 4 µA

Q(OFF)

Off Supply Current ON/OFF = Inactive, OUT = Open 1 µA

SD(OFF)

Off Switch Current ON/OFF = Inactive, V

OUT

= 0 1 µA

VIN= 5V, TA= 25°C 80 120

DS(ON)

On Resistance

= 4.2V, TA= 25°C 85 130

mΩ

VIN= 3V, TA= 25°C 100 150 VIN= 1.8V, TA= 25°C 160 250

RDS

On Resistance Temperature

2800 ppm/°C

Coefficient

ON/OFF Input Logic Low Voltage VIN= 2.7V to 5.5V

0.8 V

VIN= 2.7V to ≤ 4.2V 2

ON/OFF Input Logic High Voltage VIN= 3.3V 1.8 V

VIN= >4.2V to 5.5V 2.4

SINK

ON/OFF Input Leakage V

ON/OFF

= 5.5V 1 µA

AAT4280-1

D(ON)

Output Turn-On Delay VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 20 40 µs

Output Turn-On Rise Time VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 1000 1500 µs

D(OFF)

Output Turn-Off Delay Time VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 4 10 µs

AAT4280-2

D(ON)

Output Turn-On Delay VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 0.5 2 µs

Output Turn-On Rise Time VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 0.5 1 µs

D(OFF)

Output Turn-Off Delay Time VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 4 10 µs

AAT4280-3

D(ON)

Output Turn-On Delay VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 20 40 µs

Output Turn-On Rise Time VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 100 150 µs

D(OFF)

Output Turn-Off Delay Time VIN= 5V, R

LOAD

= 10Ω, TA= 25°C 4 10 µs

Output Pull-Down Resistance

ON/OFF = Inactive, T

= 25°C 150 250 Ω

During 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 VINoutside this range, consult typical ON/OFF threshold curve.

Page 5

Typical Characteristics

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)

OFFSW

(

ON/OFF Threshold vs. Input Voltage

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

Input Voltage (V)

ON/OFF Threshold (V)

DS(ON)

vs. Temperature

100

110

120

-40 -20 0 20 40 60 80 100

Temperature (°C)

DS(ON)

)

VIN = 5V

VIN = 3V

DS(ON)

vs. Input Voltage

110

130

150

170

190

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

Input Voltage (V)

DS(ON)

)

500mA

100mA

Quiescent Current vs. Input Voltage

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0 123456

Input Voltage (V)

Quiescent Current (

Quiescent Current vs. Temperature

-40 -20 0 20 40 60 80 100

Temperature (°C)

Quiescent Current (

VIN = 5V

VIN = 3V

AAT4280

Slew Rate Controlled Load Switch

4280.2006.11.1.4 5

Page 6

Typical Characteristics —AAT4280-1

Unless otherwise noted, VIN= 5V, TA= 25°C.

AAT4280-1 Turn-Off

= 5V; R

= 10Ω)

Time (10

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-1 Turn-Off

= 3V; R

= 6Ω)

Time (10

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-1 Turn-On

= 5V; R

= 10Ω)

Time (500

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-1 Turn-On

= 3V; R

= 6Ω)

Time (500

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280

Slew Rate Controlled Load Switch

6 4280.2006.11.1.4

Page 7

AAT4280

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

= 5V; R

= 10Ω)

Time (5

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-2 Turn-Off

= 3V; R

= 6Ω)

Time (5μs/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-2 Turn-On

= 5V; R

= 10Ω)

Time (5

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-2 Turn-On

= 3V; R

= 6Ω)

Time (5

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

Page 8

Typical Characteristics —AAT4280-3

Unless otherwise noted, VIN= 5V, TA= 25°C.

AAT4280-3 Turn-Off

= 5V; R

= 10

Ω)

Time (5μs/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-3 Turn-Off

= 3V; R

= 6Ω)

Time (5

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-3 Turn-On

= 5V; R

= 10Ω)

Time (50

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280-3 Turn-On

= 3V; R

= 6Ω)

Time (50

s/div)

ON/OFF (5V/div)

OUT

(2V/div)

IIN (200mA/div)

AAT4280

Slew Rate Controlled Load Switch

8 4280.2006.11.1.4

Page 9

Functional Description

The AAT4280 is a family of flexible P-channel MOSFET power switches designed for high-side load switching applications. There are three versions of the AAT4280 with different turn-on and turn-off characteristics to choose from, depending upon the specific requirements of an application. The first version, 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 applications. 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 voltages ranging from 1.8V to 5.5V. All versions of this device have extremely low operating current, making 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-voltage 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

UnderVoltage Lockout

Level

Shift

ON/OFF

OUT

GND

Turn-On

Slew Rate

Control

*AAT4280-3 only

Page 10

AAT4280

Slew Rate Controlled Load Switch

10 4280.2006.11.1.4

Applications Information

Input Capacitor

A 1µF or larger capacitor is typically recommended for CINin most applications. A CINcapacitor is not required for basic operation. However, CINis useful in preventing load transients from affecting upstream circuits. CINshould be located as close to the device VINpin as practically possible. Ceramic, tantalum, or aluminum electrolytic capacitors may be selected for CIN. There is no specific capacitor ESR requirement for CIN. However, for higher current operation, ceramic capacitors are recommended for CINdue to their inherent capability over tantalum capacitors to withstand 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 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, maintaining a reverse bias on the internal parasitic diode. Conditions where V

OUT

might exceed V

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 VINfor brief periods of time during normal operation, the use of a larger value CINcapacitor is

highly recommended. A larger value of C

with

respect to C

OUT

will effect a slower CINdecay rate

during shutdown, thus preventing V

OUT

from exceeding VIN. In applications where there is a greater danger of V

OUT

exceeding VINfor extended periods of time, it is recommended to place a Schottky diode from VINto V

OUT

(connecting the

cathode to VINand 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 utilizing the minimum recommended footprint, as stated in the Layout Considerations section of this datasheet.

At any given ambient temperature (TA), the maximum package power dissipation can be determined by the following equation:

D(MAX)

= [T

J(MAX)

- TA] / Θ

Constants for the AAT4280 are maximum junction temperature, T

J(MAX)

= 125°C, and package thermal

resistance, ΘJA= 120°C/W. Worst case conditions are calculated at the maximum operating temperature where TA= 85°C. Typical conditions are calculated under normal ambient conditions where T

= 25°C. At TA= 85°C, P

D(MAX)

= 333mW. At TA=

25°C, P

D(MAX)

= 833mW.

The maximum continuous output current for the AAT4280 is a function of the package power dissipation and the RDSof the MOSFET at T

J(MAX)

. The

maximum RDSof the MOSFET at T

J(MAX)

is calculated by increasing the maximum room temperature RDSby the RDStemperature coefficient. The temperature coefficient (TC) is 2800ppm/°C. Therefore,

MAX RDS125°C = RDS25°C · (1 + TC· ΔT)

MAX RDS125°C = 120mΩ · (1 + 0.0028 · (125°C - 25°C)) = 154mΩ

Page 11

AAT4280

Slew Rate Controlled Load Switch

4280.2006.11.1.4 11

For maximum current, refer to the following equation:

OUT(MAX)

< ( P

D(MAX)

/ RDS)

1/2

For example, if VIN= 5V, R

DS(MAX)

= 154mΩ and T

= 25°C, I

OUT(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 dutycycle manner.

High Peak Output Current Applications

Some applications require the load switch to operate 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 dissipation 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 operates at a continuous 100mA load current level and has short 2A current peaks, as in a GSM application. 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 R

reported for 5V can be scaled by the ratio seen in the chart to derive the RDSfor a 4V VIN: 120mΩ · 87mΩ /80mΩ = 130mΩ. De-rated for temperature: 130mΩ x (1 + 0.0028 · (125°C -25°C)) = 166mΩ. The power dissipation for a 100mA load is calculated as follows:

D(MAX)

= I

OUT

· R

D(100mA)

= (100mA)2· 166mΩ

D(100mA)

= 1.66mW

D(87.5%D/C)

= %DC · P

D(100mA)

D(87.5%D/C)

= 0.875 · 1.66mW

D(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:

D(MAX)

= I

OUT

· R

D(2A)

= (2A)2· 166mΩ

D(2A)

= 664mW

D(12.5%D/C)

= %DC · P

D(2A)

D(12.5%D/C)

= 0.125 · 664mW

D(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 dissipation under the varied load.

D(total)

= P

D(100mA)

+ P

D(2A)

D(total)

= 1.45mW + 83mW

D(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 ambient temperatures, the duty cycle can be further increased.

Page 12

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 R

DS(ON)

of the AAT4280, a few

circuit board layout rules should be followed: V

and V

OUT

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 connected to the ground pins should be made as large as possible. For best performance, CINand C

OUT

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.

Page 13

Ordering Information

Package Information

SOT23-6

All dimensions in millimeters.

1.90 BSC

0.95 BSC

0.45

0.15 0.10 BSC

2.85

0.15

0.075

0.40 ± 0.10 × 6

1.575

0.125

1.20

0.25

1.10

0.20

2.80

0.20

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 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.

Device Option Package Marking

Part Number (Tape and Reel)

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.

Page 14

SC70JW-8

All dimensions in millimeters.

0.225 ± 0.075

0.45

0.10

0.05

2.10 ± 0.30

2.00

0.20

° ± 3°

4° ± 4

1.75

0.10

0.85

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

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.

Page 15