MICREL MIC94042YFL

MIC94040/1/2/3
28mΩ RDSON 3A High Side Load Switch
in 1.2mm x 1.2mm MLF® package
General Description
Features
The MIC94040/1/2/3 is a family of high-side load switches
designed to operate from 1.7V to 5.5V input voltage. The load
switch pass element is an internal 28mΩ RDSON P-channel
MOSFET which enables the device to support up to 3A of
continuous current. Additionally, the load switch supports 1.5V
logic level control and shutdown features in a tiny 1.2mm x
®
1.2mm 4 pin MLF package.
The MIC94040 and MIC94041 feature rapid turn on, while the
MIC94042 and MIC94043 provide a slew rate controlled softstart turn-on of 100µs. The soft-start feature is provided to
prevent an in-rush current event from pulling down the input
supply voltage.
The MIC94041 and MIC94043 feature an active load
discharge circuit which switches in a 200Ω load when the
switch is disabled to automatically discharge a capacitive load.
An active pull-down on the enable input keeps the
MIC94040/1/2/3 in a default OFF state until the enable pin is
pulled above 1.2V. Internal level shift circuitry allows low
voltage logic signals to switch higher supply voltages. The
enable voltage can be as high as 5.5V and is not limited by
the input voltage.
The MIC94040/1/2/3 operating voltage range makes them
ideal for Lithium ion and NiMH/NiCad/Alkaline battery
powered systems, as well as non-battery powered
applications. The devices provide low quiescent current and
low shutdown current to maximize battery life.
Datasheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
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28mΩ RDSON
3A continuous operating current
®
1.2mm x 1.2mm space saving 4-pin MLF package
1.7V to 5.5V input voltage range
Internal level shift for CMOS/TTL control logic
Ultra low quiescent current
Micro-power shutdown current
Soft-Start: MIC94042, MIC94043
Load discharge circuit: MIC94041, MIC94043
Ultra fast turn off time
Junction operating temperature from -40ºC to +125ºC
Applications
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Cellular phones
Portable Navigation Devices (PND)
Personal Media Players (PMP)
Ultra Mobile PCs
Portable instrumentation
Other Portable applications
PDAs
Industrial and DataComm equipment
________________________________________________________________________________________________________
Typical Application
MIC94040 (ultra fast turn on)
MIC94042 (soft-start)
MIC94041 (ultra fast turn on with auto-dsicharge)
MIC94043 (soft-start with auto-discharge)
MLF and MicroLeadFrame is a registered trademark of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
May 2008
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Ordering Information
(1)
Part Number
Part Marking
—
P4
—
P1
—
P2
—
P3
MIC94040YFL
MIC94041YFL
MIC94042YFL
MIC94043YFL
Fast
Turn On
Soft-Start
Load
Discharge
•
•
•
•
•
•
(2)
Package
4-Pin (1.2mm x 1.2mm) MLF
®
4-Pin (1.2mm x 1.2mm) MLF
®
4-Pin (1.2mm x 1.2mm) MLF
®
4-Pin (1.2mm x 1.2mm) MLF
®
Notes:
®
1. MLF Pin 1 Identifier symbol is “”.
®
2. MLF is a GREEN RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Pin Configuration
Top View
®
4-Pin (1.2mm x1.2mm) MLF
Pin Description
Pin Number
Pin Name
1
VOUT
Drain of P-channel MOSFET.
2
GND
Ground should be connected to electrical ground.
3
VIN
Source of P-channel MOSFET.
4
EN
Enable (Input): Active-high CMOS/TTL control input for switch. Internal ~2MW Pull down resistor.
Output will be off if this pin is left floating.
May 2008
Pin Function
2
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Absolute Maximum Ratings(1)
Operating Ratings(2)
Input Voltage (VIN) ...........................................................+6V
Enable Voltage (VEN) ......................................................+6V
(3)
Continuous Drain Current (ID)
TA = 25°C ................................................................. ±3A
TA = 85°C .................................................................±2A
(4)
Pulsed Drain Current (IDP) .........................................±6.0A
(5)
Continuous Diode Current (IS) ................................–50mA
Storage Temperature (Ts) ......................... –55°C to +150°C
(6)
ESD Rating – HBM ....................................................... 3kV
Input Voltage (VIN) ..........................................+1.7 to +5.5V
Junction Temperature (TJ) .......................–40°C to +125°C
Package Thermal Resistance
®
MLF (qJC) ........................................................ 90°C/W
Electrical Characteristics
TA = 25°C, bold values indicate –40°C< TA < +85°C, unless noted.
Symbol
Parameter
Condition
Min
VEN_TH
Enable Threshold Voltage
VIN = 1.7V to 4.5V, ID = –250µA
0.4
IQ
Quiescent Current
VIN = VEN = 5.5V, ID = OPEN
Measured on VIN MIC94040, MIC94041
VIN = VEN = 5.5V, ID = OPEN
Measured on VIN MIC94042, MIC94043
Typ
Max
Units
1.2
V
0.1
1
µA
7
10
IEN
Enable Input Current
VIN = VEN = 5.5V, ID = OPEN
2.5
4
µA
ISHUT-Q
Quiescent Current (shutdown)
VIN = +5.5V, VEN = 0V, ID = OPEN
Measured on VIN
0.1
1
µA
ISHUT-SWITCH
OFF State Leakage Current
VIN = +5.5V, VEN = 0V, ID = SHORT
(7)
Measured on VOUT,
0.1
1
µA
RDS(ON)
P-Channel Drain to Source ON
Resistance
VIN = +5.0V, ID = –100mA, VEN = 1.5V
28
55
mΩ
VIN = +4.5V, ID = –100mA, VEN = 1.5V
30
60
mΩ
VIN = +3.6V, ID = –100mA, VEN = 1.5V
33
65
mΩ
VIN = +2.5V, ID = –100mA, VEN = 1.5V
45
90
mΩ
VIN = +1.8V, ID = –100mA, VEN = 1.5V
72
145
mΩ
VIN = +1.7V, ID = –100mA, VEN = 1.5V
82
160
mΩ
VIN = +3.6V, ITEST = 1mA, VEN = 0V
250
400
Ω
RSHUTDOWN
Turn-Off Resistance
(MIC94041, MIC94043)
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. With thermal contact to PCB. See thermal considerations section.
4. Pulse width <300µs with < 2% duty cycle.
5. Continuous body diode current conduction (reverse conduction, i.e. VOUT to VIN) is not recommended.
6. Devices are ESD sensitive. Handling precautions recommended. HBM (Human body model), 1.5kΩ in series with 100pF.
7. Measured on the MIC94040YFL and MIC94042YFL.
May 2008
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M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Electrical Characteristics (Dynamic)
TA = 25°C, bold values indicate –40°C< TA < +85°C, unless noted.
Symbol
Parameter
Condition
tON_DLY
Turn-On Delay Time
VIN = +3.6V, ID = –100mA, VEN = 1.5V
MIC94040, MIC94041
tON_RISE
Turn-On Rise Time
Min
Typ
Max
Units
0.97
1.5
µs
VIN = +3.6V, ID = –100mA, VEN = 1.5V
MIC94042, MIC94043
50
106
185
µs
VIN = +3.6V, ID = –100mA, VEN = 1.5V
MIC94040, MIC94041
0.5
0.9
5
µs
VIN = +3.6V, ID = –100mA, VEN = 1.5V
MIC94042, MIC94043
50
116
200
µs
tOFF_DLY
Turn-Off Delay Time
VIN = +3.6V, ID = –100mA, VEN = 0V
100
200
ns
tOFF_FALL
Turn-Off Fall Time
VIN = +3.6V, ID = –100mA, VEN = 0V
20
100
ns
May 2008
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M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Typical Characteristics
May 2008
MIC94040/1/2/3
MIC94040/1/2/3
MIC94040/1/2/3
MIC94040/1
MIC94042/3
MIC94040/41
MIC94042/3
MIC94042/3
MIC94040/1
5
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Typical Characteristics
MIC94042/3
MIC94040/1
MIC94042/3
MIC94040/1
MIC94042/3
MIC94040/1/2/3
MIC94042/3
May 2008
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M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Functional Characteristics
MIC94040
May 2008
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M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
MIC94041
May 2008
8
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
MIC94042
May 2008
9
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
MIC94043
May 2008
10
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Application Information
Power Dissipation Considerations
As with all power switches, the current rating of the
switch is limited mostly by the thermal properties of the
package and the PCB it is mounted on. There is a
simple ohms law type relationship between thermal
resistance, power dissipation and temperature, which
are analogous to an electrical circuit:
Example:
A switch is intended to drive a 2A load and is placed on
a printed circuit board which has a ground plane area of
2
at least 25mm by 25mm (625mm ). The Voltage source
is a Li-ion battery with a lower operating threshold of 3V
and the ambient temperature of the assembly can be up
o
to 50 C.
Summary of variables:
ISW = 2A
VIN = 3V to 4.2V
o
TA = 50 C
o
RqJC = 90 C/W from Datasheet
o
RqCA = 53 C/W Read from Graph in Figure 3
Figure 1. Simple Electrical Circuit
From this simple circuit we can calculate Vx if we know
Isource, Vz and the resistor values, Rxy and Ryz using
the equation:
Vx = Isource ◊ (Rxy + Ryz)+ Vz
Thermal circuits can be considered using these same
rules and can be drawn similarly by replacing current
sources with power dissipation (in Watts), resistance
o
with thermal resistance (in C/W) and voltage sources
o
with temperature (in C).
Figure 3. Excerpt from the LDO Book
2
PDISS = ISW x RSWmax
The worst case switch resistance (RSWmax) at the lowest
VIN of 3V is not available in the datasheet, so the next
lower value of VIN is used.
Figure 2. Simple Thermal Circuit
RSWmax @ 2.5v = 90mW
Now replacing the variables in the equation for Vx, we
can find the junction temperature (TJ) from power
dissipation, ambient temperature and the known thermal
resistance of the PCB (RqCA) and the package (RqJC).
o
If this were a figure for worst case RSWmax for 25 C, an
additional consideration is to allow for the maximum
o
junction temperature of 125 C, the actual worst case
resistance in this case can be 30% higher (See RDSON
variance vs. temperature graph). However, 90mΩ is the
maximum over temperature.
Therefore:
2
TJ = 2 x 0.090 x (90+53) + 50
o
TJ = 101 C
o
This is below the maximum 125 C.
TJ = PDISS x (RqJC + RqCA) + TA
2
PDISS is calculated as ISWITCH x RSWmax. RqJC is found in
the operating ratings section of the datasheet and RqCA
(the PCB thermal resistance) values for various PCB
copper areas is discussed in the document “Designing
with Low Dropout Voltage Regulators” available from the
Micrel website (LDO Application Hints).
May 2008
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M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
Package Information
®
4-Pin (1.2mm x 1.2mm) MLF
May 2008
12
M9999-053008-A
Micrel, Inc.
MIC94040/1/2/3
®
Suggested Landing Pattern for 4 Pin (1.2mm x 1.2mm) MLF
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its
use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical
implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
© 2008 Micrel, Incorporated.
May 2008
13
M9999-053008-A