Rev. 1.5 July 2011 www.aosmd.com Page 1 of 12
AOZ1342
Dual Channel USB Switch
General Description
The AOZ1342 power-distribution switches is intended
for applications where heavy capacitive loads and
short-circuits are likely to be encountered. This device
incorporates N-channel MOSFET power switches for
power-distribution systems that require multiple power
switches in a single package. Each switch is controlled
by a logic enable input. Gate drive is provided by an
internal charge pump designed to control the power-switch
rise times and fall times to minimize current surges
during switching. The charge pump requires no external
components and allows operation from supplies as low
as 2.7 V.
The AOZ1342 offers 1.5 A of maximum continuous
current.
The AOZ1342 is available in an Exposed Pad SO-8
package and is rated over a -40 °C to +85 °C ambient
temperature range.
Features
zTypical 70 mΩ (NFET)
z1.5 A maximum continuous current
zTwo enable options: EN or EN
zVin range: 2.7 V to 5.5 V
zOpen Drain Fault Flag
zFault Flag deglitched (blanking time)
zThermal shutdown
zReverse current blocking
zExposed pad SO-8 package
Applications
zNotebook Computers
zDesktop Computers
Typical Application
AOZ1342
IN
OC1
EN2/EN2
OC2
EN1/EN1
OUT1
OUT2
GND
VIN
Cx
0.1μF
Cx
22μF
Cx
0.1μF
Vout
Vout
Cx
RxRx
Cx
22μF
LOAD
LOAD
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 2 of 12
Ordering Information
*Contact factory for availability
AOS Green Products use reduced levels of Halogens, and are also RoHS compliant.
Please visit www.aosmd.com/web/quality/rohs_compliant.jsp for additional information.
Pin Configuration
Pin Description
Part Number
Maximum
Continuous Current Typical Short-circuit
Current Limit Enable
Setting Package Output
Discharge EnvironmentalChannel 1 Channel 2 Channel 1 Channel 2
AOZ1341AI
1 A 1A 1.5 A 1.5 A
Active Low SO-8
No Green Product
RoHS Compliant
AOZ1341EI EPAD MSOP-8
AOZ1341AI-1 Active High SO-8
AOZ1341EI-1 EPAD MSOP-8
AOZ1342PI 1.5 A 1.5A 2 A 2 A Active Low EPAD SO-8
AOZ1342PI-1 Active High EPAD SO-8
AOZ1343AI*
1.5 A 0.5A 2 A 0.75 A
Active Low SO-8
AOZ1343EI* EPAD MSOP-8
AOZ1343AI-1* Active High SO-8
AOZ1343EI-1* EPAD MSOP-8
AOZ1312AI-1 1.5 A None 2 A None Active High SO-8
AOZ1312EI-1 EPAD MSOP-8
AOZ1310CI-1 0.5 A None 0.75 A None Active High SOT23-5
Pin Name Pin Number Pin Function
GND 1 Ground
IN 2 Input voltage
EN1/EN1 3 Enable input, logic high/logic low turns on power switch IN-OUT1
EN2/EN2 4 Enable input, logic high/logic low turns on power switch IN-OUT2
OC2 5 Overcurrent, open-drain output, active low, IN-OUT1
OUT2 6 Power-switch output, IN-OUT1
OUT1 7 Power-switch output, IN-OUT2
OC1 8 Overcurrent, open-drain output, active low, IN-OUT2
OC1
OUT1
OUT2
OC2
1
2
3
4
GND
IN
EN1/EN1
EN2/EN2
Exposed Pad SO-8
(Top View)
8
7
6
5
PAD
AOZ1342
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Absolute Maximum Ratings
Exceeding the Absolute Maximum Ratings may da mage the
device.
Note:
1. Devices are inherently ESD sensitive, handling precautions are
required. Human body model is a 100 pF capacitor discharging
through a 1.5 kΩ resistor.
Recommended Operating Conditions
The device is not guaranteed to operate beyon d the
Recommended Operating Conditions.
Parameter Rating
Input Voltage (VIN)6 V
Enable Voltage (VEN)6 V
Storage Temperature (TS) -55 °C to +150 °C
Maximum Continuous Current 1.5 A
ESD Rating(1) 2 kV
Parameter Rating
Input Voltage (VIN) +2.7 V to +5.5 V
Junction Temperature (TJ) -40 °C to +125 °C
Package Thermal Resistance
Exposed Pad SO-8 (ΘJA) 45 °C/W
Electrical Characteristics
TA = 25 °C, VIN = VEN = 5.5 V, unless otherwise specified.
Symbol Parameter Conditions Min. Typ. Max. Units
POWER SWITCH
RDS(ON) Switch On-Resistance VIN = 2.7 V to 5 V, IO = 0.5 A/1.5 A 70 135 mΩ
trRise Time, Output VIN = 5.5 V CL = 1 μF, R L = 5 Ω0.6 1.5 ms
VIN = 2.7 V 0.4 1
tfFall time, Output VIN = 5.5 V 0.05 0.5 ms
VIN = 2.7 V 0.05 0.5
FET Leakage Current Out connect to ground,
2.7 V ≤ VIN ≤ 5.5 V,
V(ENx) = VIN or V(ENx) = 0 V
-40 °C ≤ TJ ≤ 125 °C(2) 1μA
ENABLE INPUT EN OR EN
VIH High-level Input Voltage 2.7 V ≤ VIN ≤ 5.5 V 2.0 V
VIL Low-level Input Voltage 2.7 V ≤ VIN ≤ 5.5 V 0.8 V
IIInput Current -0.5 0.5 μA
ton Turn-on Time CL = 100 μF, R L = 5 Ω3ms
toff Turn-off Time CL = 100 μF, RL = 5 Ω10
CURRENT LIMIT
IOS Short-circuit Output
Current (per Channel)
V(IN) = 2.7 V to 5.5 V, OUT connected to GND,
device enable into short-circuit, Channel 1 or 2
1.6 2.0 2.4 A
IOC_TRIP Overcurrent Trip
Threshold (per Channel)
V(IN) = 5 V, current ramp (≤ 100 A/s) on OUT,
Channel 1 or 2
1.6 2.2 2.5 A
SUPPLY CURRENT
Supply Current, Low-level
Output
No load on OUT,
2.7 V ≤ VIN ≤ 5.5 V,
V(ENx) = VIN or V(ENx) = 0 V
TJ = 25°C 0.5 1 μA
-40 °C ≤ TJ ≤ 125 °C(2) 0.5 5
Supply current, High-level
Output
No load on OUT,
V(ENx) = 0 V or V(ENx) = 5.5 V
TJ = 25 °C 65 81 μA
-40 °C ≤ TJ ≤ 125 °C(2) 65 90
Reverse Leakage Current V(OUTx) = 5.5 V, IN = ground 0.2 μA
AOZ1342
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Note:
2. Parameters are guaranteed by design only and not production tested.
UNDERVOLTAGE LOCKOUT
Low-level voltage, IN 2.0 2.5 V
Hysteresis, IN 200 mV
OVERCURRENT OC1 AND OC2
Output Low Voltage
VOL(OCx)
IO(OCx) = 5 mA 0.4 V
Off-state Current VO(OCx) = 5 V or 3.3 V 1 μA
OC_L Deglitch OCx assertion or deassertion 4 8 15 ms
THERMAL SHUTDOWN
Thermal Shutdown
Threshold
135 °C
Recovery from Thermal
Shutdown
105 °C
Hysteresis 30 °C
Electrical Characteristics (Continued)
TA = 25 °C, VIN = VEN = 5.5 V, unless otherwise specified.
Symbol Parameter Conditions Min. Typ. Max. Units
AOZ1342
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Functional Block Diagram
Deglitch
Deglitch
OC1
EN1/EN1
IN
EN2/EN2
OC2
OUT1
OUT2
Thermal
Shutdown
Thermal
Shutdown
Current
Limit
Gate Driver
Enable 1
Enable 2
2.2 V
Gate Driver
AOZ1342
Current
Limit
UVLO
Comparator
AOZ1342
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Functional Characteristics
Figure 1. Turn-On Delay and Rise Time
with 1μF Load (Active High)
Figure 2. Turn-Off Delay and Fall Time
with 1μF Load (Active High)
Figure 3. Turn-On Delay and Rise Time
with 100μF Load (Active High)
Figure 4. Turn-Off Delay and Fall Time
with 100μF Load (Active High)
Figure 5. Short-circuit Current, Device Enable
to Short (Active High)
Figure 6. 0.6Ω Load Connected to Enable to Device
(Active High)
EN
5V/div
VOUT
2V/div
EN
5V/div
VOUT
2V/div
EN
2V/div
IOUT
1A/div
OC
2V/div
IOUT
1A/div
EN
5V/div
VOUT
2V/div
EN
5V/div
VOUT
2V/div
400μs/div 400μs/div
400μs/div 400μs/div
400μs/div 2ms/div
RL = 5Ω
CL = 1μF
TA = 25°C
RL = 5Ω
CL = 1μF
TA = 25°C
RL = 5Ω
CL = 100μF
TA = 25°C
RL = 5Ω
CL = 100μF
TA = 25°C
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 7 of 12
Typical Characteristics
Figure 7. Supply Current, Output Enabled
vs. Junction Temperature
70
60
50
40
30
20
10
0
Junction Temperature (
°
C)
Supply Current (μA)
Vin=2.5V
Vin=3.3V
Vin=5V
Vin=5.5V
Figure 8. Supply Current, Output Disabled
vs. Junction Temperature
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Junction Temperature (°C)
Supply Current (μA)
Figure 9. Rds(on) vs. Ambient Temperature
160
140
120
100
80
60
40
20
0
Ambient Temperature (°C)
Vin=2.5V
Vin=3.3V
Vin=5V
Vin=5.5V
Figure 10. UVLO Threshold vs. Junction Temperature
2.10
2.12
2.14
2.16
2.18
2.2
2.22
2.24
2.26
2.28
2.30
Junction Temperature (°C)
Threshold (V)
Rising
Falling
-50 0 50 100 150 -50 0 50 100 150
-50 0 50 100 150
-40 -20 0 20 40 60 80
Vin=2.5V
Vin=3.3V
Vin=5V
Vin=5.5V
Rdson (mΩ)
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 8 of 12
Detailed Description
The AOZ1342 family of power-distribution switches are
intended for applications where heavy capacitive loads
and short-circuits are likely to be encountered. This
device incorporates 70 mΩ N-channel MOSFET power
switches for power-distribution systems that require
multiple power switches in a single package. Each switch
is controlled by a logic enable input. Gate drive is
provided by an internal charge pump designed to control
the power-switch rise times and fall times to minimize
current surges during switching. The charge pump
requires no external components and allows operation
from supplies as low as 2.7 V.
Thermal Shut-down Protection
When the output load exceeds the current-limit threshold
or a short is present, the device limits the output current
to a safe level by switching into a constant-current mode,
pulling the overcurrent (OC) logic output low.
During current limit or short circuit conditions, the
increasing power dissipation in the chip causes the die
temperature to rise. When the die temperature reaches a
certain level, the thermal shutdown circuitry will shutdown
the device. The thermal shutdown will cycle repeatedly
until the short circuit condition is resolved.
Applications Information
Input Capacitor Selection
The input capacitor prevents large voltage transients
from appearing at the input, and provides the
instantaneous current needed each time the switch turns
on and to also limit input voltage drop. The input
capacitor also prevents high-frequency noise on the
power line from passing through the output of the power
side. The choice of input capacitor is based on its ripple
current and voltage ratings rather than its capacitor
value. The input capacitor should be located as close as
possible to the VIN pin. A 0.1 μF ceramic cap is
recommended. However, a higher value capacitor will
reduce the voltage drop at the input.
Output Capacitor Selection
The output capacitor acts in a similar way. A small 0.1 μF
capacitor prevents high-frequency noise from going into
the system. Also, the output capacitor has to supply
enough current for the large load that it may encounter
during system transients. This bulk capacitor must be
large enough to supply a fast transient load in order to
prevent the output from dropping.
Power Dissipation Calculation
Calculate the power dissipation for normal load condition
using the following equation:
PD = RON x (IOUT)2
The worst case power dissipation occurs when the load
current hits the current limit due to over-current or short
circuit faults. The power dissipation under these
conditions can be calculated using the following
equation:
PD = (VIN – VOUT) x ILIMIT
Layout Guid elines
Good PCB layout is important for improving the thermal
and overall performance of AOZ1342. To optimize the
switch response time to output short-circuit conditions,
keep all traces as short as possible to reduce the effect of
unwanted parasitic inductance. Place the input and
output bypass capacitors as close as possible to the IN
and OUT pins. The input and output PCB traces should
be as wide as possible for the given PCB space. Use a
ground plane to enhance the power dissipation capability
of the device.
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 9 of 12
USB Power Distribution Application
Figure 11. Typical Six-Port USB Host/Self-Powered Hub Applications Circuitry
AOZ1342
IN
D+
VBUS
D-
OUT1
OUT2
GND
Power Supply
Cx
0.1μF
Cx
22μF
0.1μF10kΩ10kΩ
GND
USB
Controller
D+
VBUS
D-
Cx
0.1μF
Cx
22μFGND
D+
VBUS
D-
Cx
0.1μF
Cx
22μFGND
D+
VBUS
D-
Cx
0.1μF
Cx
22μFGND
D+
VBUS
D-
Cx
0.1μF
Cx
22μFGND
D+
VBUS
D-
Cx
0.1μF
Cx
22μFGND
OC1
EN2/EN2
OC2
EN1/EN1
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 10 of 12
Package Dimensions, Exposed Pad SO-8
Notes:
1. Package body sizes exclude mold flash and gate burrs.
2. Dimension L is measured in gauge plane.
3. Tolerance 0.10mm unless otherwise specified.
4. Controlling dimension is millimeter, converted inch dimensions are not necessarily exact.
5. Die pad exposure size is according to lead frame design.
6. Followed from JEDEC MS-012
Symbols
A
A1
A2
B
C
D
D0
D1
E
e
E1
E2
E3
L
y
θ
| L1–L1' |
L1
Dimensions in millimeters
RECOMMENDED LAND PATTERN
Min.
1.40
0.00
1.40
0.31
0.17
4.80
3.20
3.10
5.80
—
3.80
2.21
0.40
—
0°
—
D0
UNIT: mm
θ
Nom.
1.55
0.05
1.50
0.406
—
4.96
3.40
3.30
6.00
1.27
3.90
2.41
0.40 REF
0.95
—
3°
0.04
1.04 REF
Max.
1.70
0.10
1.60
0.51
0.25
5.00
3.60
3.50
6.20
—
4.00
2.61
1.27
0.10
8°
0.12
Dimensions in inches
D1
E1 E
E3E2
Note 5
L1'
L1
L
Gauge plane
0.2500
C
D
7 (4x)
B
3.70
2.20
2.87
2.71
5.74
1.27
0.80
0.635
eA1
A2 A
Symbols
A
A1
A2
B
C
D
D0
D1
E
e
E1
E2
E3
L
y
θ
| L1–L1' |
L1
Min.
0.055
0.000
0.055
0.012
0.007
0.189
0.126
0.122
0.228
—
0.150
0.087
0.016
—
0°
—
Nom.
0.061
0.002
0.059
0.016
—
0.195
0.134
0.130
0.236
0.050
0.153
0.095
0.016 REF
0.037
—
3°
0.002
0.041 REF
Max.
0.067
0.004
0.063
0.020
0.010
0.197
0.142
0.138
0.244
—
0.157
0.103
0.050
0.004
8°
0.005
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 11 of 12
Tape and Reel Dimensions, Exposed Pad SO-8
Carrier Tape
Reel
Tape Size
12mm
Reel Size
ø330
M
ø330.00
±0.50
Package
SO-8
(12mm)
A0
6.40
±0.10
B0
5.20
±0.10
K0
2.10
±0.10
D0
1.60
±0.10
D1
1.50
±0.10
E
12.00
±0.10
E1
1.75
±0.10
E2
5.50
±0.10
P0
8.00
±0.10
P1
4.00
±0.10
P2
2.00
±0.10
T
0.25
±0.10
N
ø97.00
±0.10
K0
UNIT: mm
B0
G
M
W1
S
K
H
N
W
V
R
Trailer Tape
300mm min. or
75 empty pockets
Components Tape
Orientation in Pocket
Leader Tape
500mm min. or
125 empty pockets
A0
P1
P2
Feeding Direction
P0
E2
E1
E
D0
T
D1
W
13.00
±0.30
W1
17.40
±1.00
H
ø13.00
+0.50/-0.20
K
10.60
S
2.00
±0.50
G
—
R
—
V
—
Leader/Trailer and Orientation
UNIT: mm
AOZ1342
Rev. 1.5 July 2011 www.aosmd.com Page 12 of 12
Part Marking
Z1342PI
FAY Part Number Code
Assembly Lot Code
Year & Week Code
WLT
Fab Code & Assembly
Location Code
AOZ1342PI
(Exposed Pad SO-8)
Z1342PI1
FAY Part Number Code
Assembly Lot Code
Year & Week Code
WLT
Fab Code & Assembly
Location Code
AOZ1342PI-1
(Exposed Pad SO-8)
As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant into
the body or (b) support or sustain life, and (c) whose
failure to perform when properly used in accordance
with instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of
the user.
2. A critical component in any component of a life
support, device, or system whose failure to perform can
be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or
effectiveness.
This datasheet contains preliminary data; supplementary data may be published at a later date.
Alpha & Omega Semiconductor reserves the right to make changes at any time without notice.
LIFE SUPPORT POLICY
ALPHA & OMEGA SEMICONDUCTOR PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL
COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS.
