MIC2005/2015
Fixed Current Limit
Power Distribution Switch
Kickstart™ is a trademark of Micrel, Inc
MLF and MicroLeadFrame are trademarks of Amkor Technology, Inc.
Protected by U.S. Patent No. 7,170,732
UL Certification No. E179633
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
General Description
MIC2005/2015 is a current limiting, high-side power
switch, designed for general purpose power distribution
and control in digital televisions (DTV), printers, set top
boxes (STB), PCs, PDAs, and other peripheral devices.
MIC2005/2015 primary functions are current limiting and
power switching. It is thermally protected and will
shutdown should its internal temperature reach unsafe
levels, protecting both the device and the load, under
high current or fault conditions.
Features include fault reporting, with fault blanking to
eliminate noise-induced false alarms, output slew rate
limiting, under voltage detection, automatic-on output,
and enable pin with choice of either active low or active
high enable. The FET is self-contained, with the current
limit value being factory set to one of several convenient
levels.
MIC2015 offers a unique new patented feature:
Kickstart
, which allows momentary high current
surges to pass unrestricted without sacrificing overall
system safety.
MIC2005/2015 is an excellent choice for USB and IEEE
1394 (FireWire) applications or for any system where
current limiting and power control are desired.
The MIC2005/2015 is offered in space saving 5-pin
SOT-23, 6-pin SOT-23, and 2mm x 2mm MLF
packages.
Data sheets and support documentation can be found
on Micrel’s web site at www.micrel.com.
Features
70m typical on-resistance
Enable active high or active low
2.5V - 5.5V operating range
Pre-set current limit values of 0.5 A, 0.8 A, and 1.2 A
Automatic-on output after fault
Thermal Protection
Under voltage lock-out (UVLO)
Low quiescent current
UL Certified
Applications
Digital televisions (DTV)
Set top boxes
PDAs
Printers
USB / IEEE 1394 Power Distribution
Desktop and Laptop PCs
Game consoles
Docking stations
Chargers
UL Certification Required
_________________________________________________________________________________________________________
Typical Application
MIC2005/2015
Figure 1. Typical Application Circuit
January 2008
M9999-011708-
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(408) 944-0800
Micrel MIC2005/2015
January 2008 2
M9999-011708-
MIC2005/2015 Pin Functions
Part Number Pin Function
Normal Limiting Kickstart I Limit4 I Adj. Enable C
SLEW
FAULT/
DLM3 Load
Discharge
2003 2013 -- -- -- -- -- --
2004 2014 -- -- -- --
20051 2015 -- -- --
20052
X
-- -- --
2006 2016
Fixed
-- -- --
2007 2017 -- --
2008 2018 -- -- --
2009 2019
Adj.
-- -- --
Notes: 1. C
SLEW
available on 5-Pin SOT-23-5
2. C
SLEW
not available on 5-Pin SOT-23-5
3. Dynamic Load Management
4. Adj = Adjustable current limit Fixed = Factory programmed current limit
Ordering Information
Part Number Marking2 Current Limit Kickstart Package
MIC2005-0.5YM5 F05F 0.5 A
MIC2005-0.8YM5 F08F 0.8 A
MIC2005-1.2YM5 F12F 1.2 A
SOT-23-5
MIC2005-0.5YM6 FF05 0.5 A
MIC2005-0.8YM6 FF08 0.8 A
MIC2005-1.2YM6 FF12 1.2 A
SOT-23-6
MIC2005-0.5YML E05 0.5 A
MIC2005-0.8YML E08 0.8 A
MIC2005-1.2YML E12 1.2 A
No
2 mmX2 mm MLF
MIC2015-0.5YM6 FN05 0.5 A
MIC2015-0.8YM6 FN08 0.8 A
MIC2015-1.2YM6 FN12 1.2 A
SOT-23-6
MIC2015-0.5YML N05 0.5 A
MIC2015-0.8YML N09 0.8 A
MIC2015-1.2YML N12 1.2 A
Yes
2 mmX2 mm MLF
Notes: 1. All MIC2005/2015 parts are lead free.
2. Under-bar symbol ( _ ) may not be to scale
A
(408) 944-0800
Micrel MIC2005/2015
January 2008 3
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Pin Configuration
NODAP EDISKCAB DNUORGSI
V
OUT
1
2
34
5
6
NIC
NIC
V
IN
GND
ENABLE
6-Lead 2 mm X 2 mm MLF (ML)
Top View
SOT 23-6 (M6)
Top View
SOT 23-5 (M5)
Top View
Pin Description
Pin Number
SOT-23
5-Pin 6-Pin MLF
Pin
Name Type Description
1 1 6 VIN Input
Supply input. This pin provides power to both the output switch and the
MIC2005/2015’s internal control circuitry.
2 2 5 GND -- Ground.
3 3 4 ENABLE Input Switch Enable (Input): Active-high (-1) or active-low (-2)
4 4 3 FAULT/ Output
Fault status. A logic LOW on this pin indicates the MIC2005/2015 is in current
limiting, or has been shut down by the thermal protection circuit. This is an
‘Open Drain’ output allowing logical OR’ing of multiple MIC2005/2015s.
5 2 CLSEW Input
Slew rate control. Adding a small value capacitor between this pin and VIN
slows turn-ON of the power FET.
6 6 1 VOUT Output
Switch output. The load being driven by MIC2005/2015 is connected to this
pin.
Micrel MIC2005/2015
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Absolute Maximum Ratings
(1)
V
IN
, V
OUT
............................................................ –0.3 to 6V
All other pins..................................................–0.3 to 5.5V
Power Dissipation.................................. Internally Limited
Continuous Output Current..................................... 2.25A
Maximum Junction Temperature........................... 150°C
Storage Temperature .............................. –65°C to 150°C
Operating Ratings
(2)
Supply Voltage............................................. 2.5V to 5.5V
Continuous Output Current Range .................... 0 to 2.1A
Ambient Temperature Range ....................–40°C to 85°C
Package Thermal Resistance (θ
JA
)
SOT-23-5/6 .......................................... 230°C/W
MLF 2x2 mm............................................ 90°C/W
MLF 2x2 mm θ
JC
(5)
.................................. 45°C/W
Electrical Characteristics
V
IN
= 5V, T
AMBIENT
= 25°C unless specified otherwise. Bold indicates –40°C to +85°C limits.
Symbol Parameter Conditions Min Typ Max Units
V
IN
Switch Input Voltage 2.5 5.5 V
I
IN
Internal Supply Current Switch = OFF,
ENABLE = 0V 1
5 µA
I
IN
Internal Supply Current Switch = ON, I
OUT
= 0
ENABLE = 1.5V
80 300 µA
I
LEAK
Output Leakage Current V
IN
= 5V, V
OUT
= 0 V, ENABLE
= 0 12
100 µA
70 100 m
R
DS(ON)
Power Switch Resistance V
IN
= 5V, I
OUT
= 100 mA 125 m
I
LIMIT
Current Limit: –0.5 V
OUT
= 0.8V
IN
to V
OUT
= 1V 0.5 0.7 0.9 A
I
LIMIT
Current Limit: –0.8 V
OUT
= 0.8V
IN
to V
OUT
= 1V 0.8 1.1 1.5 A
I
LIMIT
Current Limit: –1.2 V
OUT
= 0.8V
IN
, to V
OUT
= 1V 1.2 1.6 2.1 A
I
LIMIT_2nd
Secondary current limit
(Kickstart) MIC2015, V
IN
= 2.7V 2.2 4 6 A
V
IN
Rising 2.0 2.25 25 V
UVLO
THRESHOL
D
Under Voltage Lock Out
Threshold V
IN
Falling 1.9 2.15 2.4 V
V
IL
(max.) 0.5 V
V
EN
ENABLE Input Voltage V
IH
(min) 1.5 V
I
EN
ENABLE Input Current V
EN
= 0V to 5.0V 1 5 µA
V
FAULT
Fault status Output Voltage I
OL
= 10mA 0.25 0.4 V
T
J
increasing 145
OT
THRESHOLD
Over-temperature Threshold T
J
decreasing 135 °C
Micrel MIC2005/2015
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AC Characteristics
Symbol Parameter Condition Min Typ Max Units
t
RISE
Output Turn-ON rise time R
L
= 10, C
LOAD
= 1µF,
V
OUT
= 10% to 90% 500 1000 1500 µs
Time from current limiting to
FAULT/ state change.
MIC2005
20 32 49 ms
t
D_FAULT
Delay before asserting or
releasing FAULT/ Time from I
OUT
continuously
exceeding primary current limit
condition to FAULT/ state
change. MIC2015
77 128 192 ms
t
D_LIMIT
Delay before current limiting MIC2015 77 128 192 ms
t
RESET
Delay before resetting
Kickstart current limit delay,
t
LIMIT
Out of current limit following a
current limit.
MIC2015
77 128 192 ms
t
ON_DLY
Output Turn-ON Delay R
L
= 43, C
L
= 120µF,
V
EN
= 50% to V
OUT
= 90% 1000 1500 µs
t
OFF_DLY
Output Turn-OFF Delay R
L
= 43, C
L
= 120µF,
V
EN
= 50% to V
OUT
= 90% 700 µs
ESD
Symbol Parameter Condition Min Typ Max Units
V
OUT
and GND ± 4 kV V
ESD_HB
Electro Static Discharge
Voltage: Human Body Model All other pins ± 2 kV
ESD_MCHN
Electro Static Discharge
Voltage; Machine Model
All pins
Machine Model
± 200 V
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
4. Specification for packaged product only.
5. Requires proper thermal mounting to achieve this performance.
Micrel MIC2005/2015
January 2008 6
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Timing Diagrams
ENABLE
VOUT
50%
90%
10%
t
ON_DLY
t
OFF_DLY
50%
Switching Delay Times
90%
10%
90%
10%
t
FALL
t
RISE
Rise and Fall Times
90%
10%
t
RISE
VOUT
Output Rise Time
Micrel MIC2005/2015
January 2008 7
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Typical Characteristics
0
20
40
60
80
100
23456
SUPPLY CURRENT (µA)
V
IN
(V)
Supply Current
Output Enabled
-40°C
85°C
25°C
0
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
234567
SUPPLY CURRENT (µA)
V
IN
(V)
Supply Current
Output Disabled
-40°C
85°C
25°C
0
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
-50 -30 -10 10 30 50 70 90
(µA)
TEMPERATURE (°C)
Switch Leakage Current - OFF
1.25
1.30
1.35
1.40
1.45
1.50
1.55
1.60
1.65
-50-30-101030507090
I
LIMIT
(A)
TEMPERATURE (°C)
I
LIMIT
vs. Temperature
(MIC20xx-1.2)
V
IN
= 2.5V
V
IN
= 5V
V
IN
= 3V
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
-50-30-101030507090
I
LIMIT
(A)
TEMPERATURE (°C)
5V
3V
2.5V
I
LIMIT
vs. Temperature
(MIC20xx - 0.8)
Note:
Please note that the 3
plots overlay each
0.55
0.57
0.59
0.61
0.63
0.65
0.67
0.69
0.71
0.73
0.75
-50 -30 -10 10 30 50 70 90
I
LIMIT
(A)
TEMPERATURE (°C)
5V
3V
2.5V
I
LIMIT
vs. Temperature
(MIC20xx - 0.5)
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-50-30-101030507090
I
LIMIT
(A)
TEMPERATURE (°C)
I
LIMIT
vs.
Temperature
1.2A
0.8A
0.5A
0
20
40
60
80
100
22.533.544.555.5
R
ON
(mOhm)
V
IN
(V)
R
ON
vs.
Supply Voltage
0
20
40
60
80
100
120
-50 -30 -10 10 30 50 70 90
R
ON
(mOhm)
TEMPERATURE (°C)
R
ON
vs.
Temperature
2.5V
3.3V
5V
2.05
2.1
2.15
2.2
2.25
2.3
-50 0 50 100 150
THRESHOLD (V)
TEMPERATURE (°C)
UVLO Threshold
vs. Temperature
V RISING
V FALLING
Micrel MIC2005/2015
January 2008 8
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Functional Characteristics
Micrel MIC2005/2015
January 2008 9
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Micrel MIC2005/2015
January 2008 10
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Functional Diagram
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lamrehT
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TEFrorriM
yrotcaF
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timiLtnerruC
pooLlortnoc
lortnoCetaG
cigoLlortnoC
remiTyaleDdna
GND
VOUT
VIN
Figure 2 MIC2005/2015 Block Diagram
Micrel MIC2005/2015
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Functional Description
VIN and VOUT
V
IN
is both the power supply connection for the internal
circuitry driving the switch and the input (Source
connection) of the power MOSFET switch. V
OUT
is the
Drain connection of the power MOSFET and supplies
power to the load. In a typical circuit, current flows from
V
IN
to V
OUT
toward the load. Since the switch is bi-
directional when enabled, if V
OUT
is greater than V
IN
,
current will flow from V
OUT
to V
IN
.
When the switch is disabled, current will not flow to the
load, except for a small unavoidable leakage current of
a few microamps. However, should V
OUT
exceed V
IN
by
more than a diode drop (~0.6V), while the switch is
disabled, current will flow from output to input via the
power MOSFET’s body diode. This effect can be used
to advantage when large bypass capacitors are placed
on MIC2005/2015’s output. When power to the switch is
removed, the output capacitor will be automatically
discharged.
If discharging C
LOAD
is required by your application,
consider using MIC2005/2015 or MIC2007/2017 in place
of MIC2005/2015. These MIC2000 family members are
equipped with a discharge FET to insure complete
discharge of C
LOAD
.
Current Sensing and Limiting
MIC2005/2015 protects the system power supply and
load from damage by continuously monitoring current
through the on-chip power MOSFET. Load current is
monitored by means of a current mirror in parallel with
the power MOSFET switch. Current limiting is invoked
when the load exceeds an internally set over-current
threshold. When current limiting is activated the output
current is constrained to the limit value, and remains at
this level until either the load/fault is removed, the load’s
current requirement drops below the limiting value, or
the MIC2005/2015 goes into thermal shutdown.
Kickstart (MIC2015 only)
The MIC2015 is designed to allow momentary current
surges (Kickstart) before the onset of current limiting,
which permits dynamic loads, such as small disk drives
or portable printers to draw the energy needed to
overcome inertial loads without sacrificing system
safety. In this respect, the MIC2015 differs markedly
from MIC2005 and its peers, which immediately limit
load current, potentially starving the motor and causing
the appliance to stall or stutter.
During this delay period, typically 128 ms, a secondary
current limit is in effect. If the load demands a current in
excess the secondary limit, MIC2015 acts immediately
to restrict output current to the secondary limit for the
duration of the Kickstart period. After this time the
MIC2015 reverts to its normal current limit. An example
of Kickstart operation is shown below.
TUO
TUO
Figure 3. Kickstart Operation
Picture Key:
A) MIC2015 is enabled into an excessive load (slew
rate limiting not visible at this time scale) The initial
current surge is limited by either the overall circuit
resistance and power supply compliance, or the
secondary current limit, whichever is less.
B) R
ON
of the power FET increases due to internal
heating (effect exaggerated for emphasis).
C) Kickstart period.
D) Current limiting initiated. FAULT/ goes LOW.
E) V
OUT
is non-zero (load is heavy, but not a dead short
where V
OUT
= 0. Limiting response will be the same
for dead shorts).
F) Thermal shutdown followed by thermal cycling.
G) Excessive load released, normal load remains.
MIC2015 drops out of current limiting.
H) FAULT/ delay period followed by FAULT/ going
HIGH.
Under Voltage Lock Out
Under voltage lock-out insures no anomalous operation
occurs before the device’s minimum input voltage of
2.5V had been achieved. Prior to reaching this voltage,
the output switch (power MOSFET) is OFF and no
circuit functions, such as FAULT/ or ENABLE, are
considered to be valid or operative.
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ENABLE
ENABLE is a HIGH or LOW true control signal, which
activates the main MOSFET switch. ENABLE has two
voltage ranges depending on whether the switch is an
active high or active low device.. ENABLE can be wire-
OR’d with other MIC2005/2015s or similar devices
without damage to the device. ENABLE may be driven
higher than VIN, but no higher than 5.5V.
FAULT/
FAULT/ is an N-channel ‘open drain’ output, which is
asserted (LOW true) when MIC2005/2015’s either
begins current limiting or enters thermal shutdown.
In MIC2005/2015, FAULT/ asserts after a brief delay
period, usually 32 ms. This delay ensures that FAULT/
is asserted only upon valid, enduring, over-current
conditions and that transitory event error reports are
filtered out.
After a fault clears, FAULT/ remains asserted for the
delay period; 32ms for the MIC2005/2015.
Because FAULT/ is an ‘open drain’ it must be pulled
HIGH with an external resistor output and it may be
wire-OR’d with other similar outputs, sharing a single
pull-up resistor. FAULT/ may be tied to a pull-up voltage
source which is higher than VIN, but no greater than
5.5V.
Slew Rate Control (Not present with SOT23-5 (M5))
Large capacitive loads can create significant current
surges when charged through a high-side switch such
as the MIC2005/2015. For this reason, MIC2005/2015
provides built-in slew rate control to limit the initial inrush
currents upon enabling the power MOSFET switch.
Slew rate control is active upon powering up, and upon
re-enabling the load. At shutdown, the discharge slew
rate is controlled by the external load and output
capacitor.
Thermal Shutdown
Thermal shutdown is employed to protect
MIC2005/2015 from damage should the die temperature
exceed safe operating levels. Thermal shutdown shuts
off the output MOSFET if the die temperature reaches
145°C.
MIC2005/2015 will automatically resume operation
when the die temperature cools down to 135°C. If
resumed operation results in reheating of the die,
another shutdown cycle will occur and the
MIC2005/2015 will continue cycling between ON and
OFF states until the offending load has been removed.
Depending on PCB layout, package type, ambient
temperature, etc., hundreds of milliseconds may elapse
from the incidence of a fault to the output MOSFET
being shut off. This delay is due to thermal time
constants within the system itself. In no event will the
device be damaged due to thermal overload because
die temperature is monitored continuously by on-chip
circuitry.
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Application Information
I
LIMIT
vs. I
OUT
measured
MIC2005/2015’s current limiting circuitry is designed to
act as a constant current source to the load. As the load
tries to pull more than the allotted current, V
OUT
drops
and the input to output voltage differential increases.
When V
IN
-V
OUT
exceeds 1V, I
OUT
drops below I
LIMIT
to
reduce the drain of fault current on the system’s power
supply and to limit internal heating of MIC2005/2015.
When measuring I
OUT
it is important to bear this voltage
dependence in mind, otherwise the measurement data
may appear to indicate a problem when none really
exists. This voltage dependence is illustrated in Figures
4 and 5.
In Figure 4 output current is measured as V
OUT
is pulled
below V
IN
, with the test terminating when V
OUT
is 1V
below V
IN
. Observe that once I
LIMIT
is reached I
OUT
remains constant throughout the remainder of the test.
In Figure 5 this test is repeated but with V
IN
- V
OUT
exceeding 1V.
When V
IN
- V
OUT
> 1V, MIC2005/2015’s current limiting
circuitry responds by decreasing I
OUT
, as can be seen in
Figure 5. In this demonstration, V
OUT
is being controlled
and I
OUT
is the measured quantity. In real life
applications V
OUT
is determined in accordance with
Ohm’s law by the load and the limiting current.
Figure 4. I
OUT
in Current Limiting for V
OUT
1V
Figure 5. I
OUT
in Current Limiting for V
OUT
>1V
This folding back of I
LIMIT
can be generalized by plotting
I
LIMIT
as a function of V
OUT
, as shown below. The slope
of V
OUT
between I
OUT
= 0 and I
OUT
= I
LIMIT
(where I
LIMIT
=
1) is determined by R
ON
of MIC2005/2015 and I
LIMIT
.
0
0.2
0.4
0.6
0.8
1.0
1.2
0123456
NORMALIZED OUTPUT CURRENT (A)
OUTPUT VOLTAGE (V)
Normalized Output Current
vs. Output Voltage (5V)
Figure 6.
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0
0.2
0.4
0.6
0.8
1.0
1.2
0 0.5 1.0 1.5 2.0 2.5 3.0
NORMALIZED OUTPUT CURRENT (A)
OUTPUT VOLTAGE (V)
Normalized Output Current
vs. Output Voltage (2.5V)
Figure 7.
C
SLEW
(Not present with SOT23-5 (M5))
The C
SLEW
input is provided to increase control of the
output voltage ramp at turn-on. This input allows
designers the option of decreasing the output’s slew rate
(slowing the voltage rise) by adding an external
capacitance between the pin, C
SLEW
, and VIN. This
capacitance slows the rate at which the pass FET gate
voltage increases and thus, slows both the response to
an Enable command as well as VOUT’s ascent to its
final value.
Figure 8 illustrates effect of C
SLEW
on turn-ON delay
and output rise time.
Figure 8
C
SLEW
’s effect on I
LIMIT
An unavoidable consequence of adding C
SLEW
capacitance is a reduction in the MIC2005/2015’s ability
to quickly limit current transients or surges. A sufficiently
large capacitance can prevent both the primary and
secondary current limits from acting in time to prevent
damage to the MIC2005/2015 or the system from a
short circuit fault. For this reason, the upper limit on the
value of C
SLEW
is 4nF.
Kickstart (MIC2015)
Kickstart allows brief current surges to pass to the load
before the onset of normal current limiting, which
permits dynamic loads to draw bursts of energy without
sacrificing system safety.
Functionally, Kickstart is a forced override of the normal
current limiting function provided by MIC2015. The
Kickstart period is governed by an internal timer which
allows current to pass unimpeded to the load for 128ms
and then normal (primary) current limiting goes into
action.
During Kickstart a secondary current limiting circuit is
monitoring output current to prevent damage to the
MIC2015, as a hard short combined with a robust power
supply can result in currents of many tens of amperes.
This secondary current limit is nominally set at 4 Amps
and reacts immediately and independently of the
Kickstart period. Once the Kickstart timer has finished its
count the primary current limiting circuit takes over and
holds I
OUT
to its programmed limit for as long as the
excessive load persists.
Once MIC2015 drops out of current limiting the Kickstart
timer initiates a lock-out period of 128ms such that no
further bursts of current above the primary current limit,
will be allowed until the lock-out period has expired.
Kickstart may be over-ridden by the thermal protection
circuit and if sufficient internal heating occurs, Kickstart
will be terminated and I
OUT
Æ 0. Upon cooling, if the
load is still present I
OUT
Æ I
LIMIT
, not I
KICKSTART
.
Figure 9. Kickstart
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Supply Filtering
A 0.1µF to 1µF bypass capacitor positioned close to the
V
IN
and GND pins of MIC2005/2015 is both good design
practice and required for proper operation of
MIC2005/2015. This will control supply transients and
ringing. Without a bypass capacitor, large current surges
or an output short may cause sufficient ringing on V
IN
(from supply lead inductance) to cause erratic operation
of MIC2005/2015’s control circuitry. Good quality, low
ESR capacitors, such as Panasonic’s TE or ECJ series,
are suggested.
When bypassing with capacitors of 10µF and up, it is
good practice to place a smaller value capacitor in
parallel with the larger to handle the high frequency
components of any line transients. Values in the range
of 0.01µF to 0.1µF are recommended. Again, good
quality, low ESR capacitors should be chosen.
Power Dissipation
Power dissipation depends on several factors such as
the load, PCB layout, ambient temperature, and supply
voltage. Calculation of power dissipation can be
accomplished by the following equation:
()
2
OUTDS(ON)D
IRP ×=
To relate this to junction temperature, the following
equation can be used:
AA)-(JDJ
TRPT +×=
θ
Where: T
J
= junction temperature,
T
A
= ambient temperature
R
θ(J-A)
is the thermal resistance of the package
In normal operation MIC2005/2015’s Ron is low enough
that no significant I2R heating occurs. Device heating is
most often caused by a short circuit, or very heavy load,
when a significant portion of the input supply voltage
appears across MIC2005/2015’s power MOSFET.
Under these conditions the heat generated will exceed
the package and PCB’s ability to cool the device and
thermal limiting will be invoked.
In Figure 10 die temperature is plotted against I
OUT
assuming a constant case temperature of 85°C. The
plots also assume a worst case R
ON
of 140 m at a die
temperature of 135°C. Under these conditions it is clear
that an SOT-23 packaged device will be on the verge of
thermal shutdown, typically 140°C die temperature,
when operating at a load current of 1.25A. For this
reason we recommend using MLF packaged
MIC2005/2015s for any design intending to supply
continuous currents of 1A or more.
Die Temperature vs. Iout for Tcase = 85°C
0
20
40
60
80
100
120
140
160
0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
Iout - Amps
Die Temperature - °C
SOT-23
MLF
Figure 10. Die Temperature vs. I
OUT
Figure 10 assumes no backside contact is made to the
thermal pad provided on the MLF package. For optimal
performance at higher current levels, or in higher
temperature environments, thermal contact with the
PCB and the exposed power paddle on the back side of
the MLF package should be made. This significantly
reduces the package’s thermal resistance thereby
extending the MIC2005/2015’s operating range. It
should be noted that this backside paddle is electrically
active and is connected to the MIC2005/2015’s GND
pin.
Micrel
MIC2005/2015
January 2008 16
M9999-011708-
A
(408) 944-0800
Package Information
2 Vias
0.3 mm diam.
to Ground Plane
0.8 mm
1.4 mm
Figure 11. Pad for thermal mounting to PCB
6-Pin SOT-23 (M6)
Micrel
MIC2005/2015
January 2008 17
M9999-011708-
A
(408) 944-0800
Package Information (Cont.)
0.20 (0.00
8
)
0.09 (0.00
4
)
0.60 (0.024)
0.10 (0.004)
3.02 (0.119)
2.80 (0.110) 10°
0°
3.00 (0.118)
2.60 (0.102)
1.75 (0.069)
1.50 (0.059)
0.95 (0.037) REF
1.30 (0.051)
0.90 (0.035)
0.15 (0.006)
0.00 (0.000)
DIMENSIONS:
MM (INCH)
0.50 (0.020)
0.35 (0.014)
1.90 (0.075) RE
F
5-Pin SOT-23 (M5)
6 Pin 2mm × 2mm MLF (ML)
Micrel
MIC2005/2015
January 2008 18
M9999-011708-
A
(408) 944-0800
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.
© 2004 Micrel, Incorporated.