EXAR SP619EK-L

SP619
High Current Power Switch
FEATURES
• Max RDS(ON) .377 Ohms
• Overcurrent deactivation 800mA
• Max leakage current less than 2µA
while deactivated
• Small 6 pin SOT-23 package
• Built-in Over-temperature Protection
• 4.5V to 5.5V input voltage range
6
5
4
SP619
SOT23-6
APPLICATIONS
• Ultra low cost handsets
• PDA, DSC, MP3 players
• Cell phones
• Power Distribution Switch
• Battery-Charger Circuit
1
2
3
DESCRIPTION
The SP619 is a low RDS(ON) high current switch designed with precision current limiting to protect connected devices from damage due to a short circuit condition or
against current surges that may cause the supply voltages to fall out of regulation. This switch is functional over an input voltage range of 2.5V to 7V, but is targeted
at 5V applications. The SP619 is also protected from thermal overload which
limits power dissipation. In shutdown mode, the supply current drops to 2µA.
TYPICAL APPLICATION CIRCUIT
Vin
SP619
Vout
Vin
100K
Cin .1µF
Cout
.1µF
LOAD
EN
ON/OFF
80K
April 2008 Rev L
GND
SP619 High Current Power Switch
1
© 2008 EXAR Corporation
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation of the device at these ratings or any other
above those indicated in the operation sections of
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absolute maximum rating conditions for extended
periods of time may affect reliability.
VIN……….…………………………….….…-0.3V to 7V
Storage Temperature..…....……….… -65°C to 150°C
Junction Temperature..................... ……..…….150°C
Lead Temperature (Soldering, 10 sec)......…….300°C
(6'5$7,1*
Human Body Model……………………….…….2000V
Machine Model…………………………………....200V
23(5$7,1*5$7,1*6
Thermal resistance SOT23-6
Junction to Ambient……………………….….….191°C
Junction to lead ……………………...……………50°C
RECOMMENDED OPERATING CONDITIONS
8QOHVVRWKHUZLVHVSHFL¿HG9IN = 4.5V - 5.5V, CIN = 0.1µF, TA = -10°C to + 85°C
3$5$0(7(5
CONDITIONS
MIN
Operating Input Voltage
Range
TYP (Note 1)
4.5
Overcurrent Deactivation
Range
(1 9
620
Overcurrent Duration Before Deactivation
(1 9
1
Shutdown Supply Current
MAX
5.5
V
1010
mA
5.25
ms
VIN=4.5V
2
µA
Quiescent Supply Current
(1 99IN=4.5V
IOUT=0mA
350
µA
Quiescent Supply Current
(1 99IN=4.5V
IOUT=725mA
5.25
mA
VIN=4.5V IOUT=100mA
(1 9
.377
Ÿ
23
.Ÿ
55
ms
RDS(ON)
800
UNITS
Post Fault Output Load for
Recovery
(QDEOH 9
10
Post Fault Activation Turn
On Time
(QDEOH 9
1
SP619 will self recover
when temperature drops
below the trip point .
120
150
180
°C
90
120
135
°C
.5
V
1.4
V
Thermal Shutdown Die
Temperature
Thermal Restart Die Temperature
(1$%/(/RJLF/2:
(1$%/(3LQ/RJLF+,*+
Driver is disabled
Driver is active
.655
15
Turn On Delay
RL NŸ&L= 0.01µF
(Note 2,3)
600
µs
Turn Off Delay
RL NŸ&L= 0.01µF
(Note 2,4)
200
µs
Rise Time
RL NŸ&L= 0.01µF
(Note 2)
100
µs
Fall Time
RL NŸ&L= 0.01µF
(Note 2)
2500
µs
1RWH7\SLFDOVDUH7J=25°C
1RWH&KDUDFWHUL]HGQRWWHVWHG
1RWH7XUQRQGHOD\LVPHDVXUHGIURPWKHWLPHWKHHQDEOHSLQLVWXUQHGRQWRWKHWLPHLWWDNHVWKHRXWSXWWRULVHWRRILWV ¿QDOYDOXH
1RWH7XUQRIIGHOD\LVPHDVXUHGIURPWKHWLPHWKHHQDEOHSLQLVWXUQHGWRWKHWLPHLWWDNHVIRUWKHRXWSXWWRIDOOWRRILWV current value.
April 2008 Rev L
SP619 High Current Power Switch
2
© 2008 EXAR Corporation
FAULT AND RECOVERY TRUTH TABLE*
Enable
Load
Temperature
(TJ)
Previous
State
Switch
Current State/Fault
(Note*)
Low
X
X
X
Open
Off
High
< 800 mA
< 163ºC
Off
Closed
Normal
High
< 800 mA
> 163ºC
Off
Open
Thermal Cutoff
High
> 800 mA
< 163ºC
Off
Open
Overcurrent
High
> 800 mA
> 163ºC
Off
Open
Thermal Cutoff,
Overcurrent
High
NŸ
< 163ºC
Overcurrent
Open
Load Condition
High
NŸ
> 163ºC
Overcurrent
Open
Thermal Cutoff,
Overcurrent, Load
Condition
High
!NŸ
< 163ºC
Overcurrent
Closed
Normal
High
!NŸ
> 163ºC
Overcurrent
Open
Thermal Cutoff
High
NŸ
< 120ºC
Thermal Cutoff
Open
Load Condition
High
NŸ
> 120ºC
Thermal Cutoff
Open
Load Condition,
Thermal Cutoff
High
!NŸ
< 120ºC
Thermal Cutoff
Closed
Normal
High
!NŸ
> 120ºC
Thermal Cutoff
Open
Thermal Cutoff
1RWH7KLVWDEOHLVIRUIDXOWFRQGLWLRQVQRWIRUFRQWLQXRXVRSHUDWLRQHOVHGDPDJHWRWKHGHYLFHPD\
occur. In order to recover to the normal state after a Thermal Cutoff fault, the part’s junction temperDWXUHPXVWGHFUHDVHEHORZž&DQGWKHORDGRQLWVRXWSXWPXVWEHJUHDWHUWKDQNŸ
PIN ASSIGNMENTS
PIN
NUMBER
PIN
NAME
FUNCTION
1
VIN
Input power supply pin (4.5V to 5.5V)
2
*1'
*URXQGFRQQHFWLRQ
3
(QDEOH
A logic high turns on the switch
4
NC
No connect
5
NC
No connect
6
VOUT
Switch output
April 2008 Rev L
SP619 High Current Power Switch
3
© 2008 EXAR Corporation
THEORY OF OPERATIION
The SP619 is a switch capable of handling
up to 800mA of current.
inrush current that can be encountered.
At 6 volts in, the inrush current was about
250mA into a 100µF capacitor.
The SP619 is targeted as a for 5V USB
protection power distribution switch. And
can be used in general power distribution
applications where short circuits are likely
to be encountered.
Output Voltage Rise Time
The output voltage of the SP619 has an
output capacitance dependency on the
slope of VOUT. A simple RC circuit is created when the switch is turned on.
(TXDWLRQ
-t
V(t)=VO+VIN
RDS(ON) • COUT
1-e
Short circuit operation
When the SP619 enters a short circuit condition, the switch is disabled. The output
of the SP619 will not restart until the outSXWLPSHGDQFHLVJUHDWHUWKDQ.Ÿ7KH
enable pin can be used to re-enable the
SP619 into any load condition that is not
a fault condition. Refer to the truth table on
page 4 for more information on the different SP619 switch states. The typical deactivation time is about 2ms.
(
(
Where VO is initial Voltage condition typically 0V
VIN is the input voltage
RDS(ON) is the switch resistance
COUT is the output capacitance
For 4.2V VIN and 100µF output capacitance
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4.17
Enable
The enable pin allows easy control of the
SP619. The enable pin should not be enabled high prior to a voltage being present on the input of the device. The enable
pin should not exceed the input voltage by
PRUHWKDQ9GXHWRDQLQWHUQDO(6'GLode. Doing so will affect the operation of
the SP619 and could damage the device.
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*1' VKRXOG EH XVHG RQ WKH HQDEOH SLQ
This resistor will pull the enable low when
an enable signal is not present. This prevents the SP619 from falsely turning on.
The enable pin can also be used to restart
the part into a load condition that is high in
current. Please refer to the truth table on
page 4 for more details.
3.33
VOUT 2.5
1.67
0.83
0
0
0.33
0.67
1
time in uS
1.33
1.67
2
This is comparable to actual measured
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Inrush Current
The SP619 is a simple resistive switch.
When the switch is turned on into a highly
FDSDFLWLYHORDGWKHUHFRXOGEHDVLJQL¿FDQW
April 2008 Rev L
SP619 High Current Power Switch
4
© 2008 EXAR Corporation
THEORY OF OPERATION
Overtemperature Protection
The SP619 has built-in overtemperature
protection to protect the part against damage if the die temperature gets too hot. The
typical thermal cutoff is about 150ºC. The
part will self recover if the temperature drops
below the thermal restart threshold of about
120ºC.
Layout Considerations
The input and output decoupling capacitors
should be placed as close as possible to the
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EH VWLWFKHG WR WKH *1' SODLQ WR KHOS ZLWK
thermal performance. The input and output
traces should be as large as possible. The
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and should be placed close to the output decoupling cap.
Vin
146-6642-00
U1 Vout
ON/OFF
GND
Solved by
TM
SP619
Recommended Layout
April 2008 Rev L
SP619 High Current Power Switch
5
© 2008 EXAR Corporation
6 PIN SOT-23
April 2008 Rev L
SP619 High Current Power Switch
6
© 2008 EXAR Corporation
ORDERING INFORMATION
Part number
Temperature range
Package Type
63(./
From -10 to +85ºC
Lead Free 6 pin SOT23
63(./75
From -10 to +85ºC
Lead Free 6 pin SOT23
/TR = Tape and Reel.
For further assistance:
Email: [email protected]
EXAR Technical Documentation: http://www.exar.com/TechDoc/default.aspx?
Exar CorporationHeadquarters and Sales Office
48720 Kato Road
Fremont, CA 94538
main: 510-668-7000
fax: 510-668-7030
EXAR Corporation reserves the right to make changes to the products contained in this publication in order
to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any
circuits described herein, conveys no license under any patent or other right, and makes no representation
that the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration
purposes and may vary depending upon a user’s specific application. While the information in this publication
has been carefully checked; no responsibility, however, is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the
failure or malfunction of the product can reasonably be expected to cause failure of the life support system or
to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless
EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has
been minimized; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately
protected under the circumstances.
April 2008 Rev L
SP619 High Current Power Switch
7
© 2008 EXAR Corporation