MIC2005-1.2YM5TX [MICROCHIP]
IC,PERIPHERAL DRIVER,1 DRIVER,TSOP,5PIN,PLASTIC;型号: | MIC2005-1.2YM5TX |
厂家: | MICROCHIP |
描述: | IC,PERIPHERAL DRIVER,1 DRIVER,TSOP,5PIN,PLASTIC 驱动 |
文件: | 总18页 (文件大小:1066K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
MIC2005/2015
Fixed Current Limit
Power Distribution Switch
General Description
Features
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.
• 70mΩ 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
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.
• Under voltage lock-out (UVLO)
• Low quiescent current
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.
• UL Certified
Applications
• Digital televisions (DTV)
• Set top boxes
• PDAs
MIC2015 offers a unique new patented feature:
• Printers
Kickstart
™
, which allows momentary high current
• USB / IEEE 1394 Power Distribution
• Desktop and Laptop PCs
• Game consoles
• Docking stations
• Chargers
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.
• UL Certification Required
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.
_________________________________________________________________________________________________________
Typical Application
MIC2005/2015
Figure 1. Typical Application Circuit
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
M9999-011708-A
(408) 944-0800
January 2008
Micrel
MIC2005/2015
MIC2005/2015 Pin Functions
Part Number
Pin Function
CSLEW FAULT/
Load
Discharge
4
3
Normal Limiting
Kickstart
I Adj.
Enable
I Limit
DLM
2003
2004
2013
2014
2015
X
--
--
--
--
--
--
--
--
--
--
--
▲
--
--
--
--
▲
--
▲
▲
▲
▲
▲
▲
▲
1
Fixed
Adj.
--
▲
▲
▲
--
2005
2
--
--
2005
2006
2007
2008
2009
2016
2017
2018
2019
--
▲
▲
▲
--
--
▲
▲
▲
--
▲
--
--
▲
--
Notes: 1. CSLEW available on 5-Pin SOT-23-5
2. CSLEW not available on 5-Pin SOT-23-5
3. Dynamic Load Management
4. Adj = Adjustable current limit
Fixed = Factory programmed current limit
Ordering Information
2
Marking
Part Number
Current Limit
0.5 A
Kickstart
Package
MIC2005-0.5YM5
MIC2005-0.8YM5
MIC2005-1.2YM5
MIC2005-0.5YM6
MIC2005-0.8YM6
MIC2005-1.2YM6
MIC2005-0.5YML
MIC2005-0.8YML
MIC2005-1.2YML
MIC2015-0.5YM6
MIC2015-0.8YM6
MIC2015-1.2YM6
MIC2015-0.5YML
MIC2015-0.8YML
MIC2015-1.2YML
F05F
F08F
F12F
FF05
FF08
FF12
E05
0.8 A
SOT-23-5
1.2 A
0.5 A
No
0.8 A
SOT-23-6
1.2 A
0.5 A
E08
0.8 A
2 mmX2 mm MLF
SOT-23-6
E12
1.2 A
FN05
FN08
FN12
N05
0.5 A
0.8 A
1.2 A
Yes
0.5 A
N09
0.8 A
2 mmX2 mm MLF
N12
1.2 A
Notes: 1. All MIC2005/2015 parts are lead free.
2. Under-bar symbol ( _ ) may not be to scale
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M9999-011708-A
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January 2008
Micrel
MIC2005/2015
Pin Configuration
VOUT
1
VIN
6
5
4
PAD ON
BACKSIDE
IS GROUND
NIC
GND
2
NIC
ENABLE
3
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
Pin
MLF
Name
Type
Description
5-Pin
6-Pin
Supply input. This pin provides power to both the output switch and the
MIC2005/2015’s internal control circuitry.
1
1
6
VIN
Input
2
3
2
3
5
4
GND
--
Ground.
ENABLE
Input
Switch Enable (Input): Active-high (-1) or active-low (-2)
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.
4
4
3
FAULT/
Output
Slew rate control. Adding a small value capacitor between this pin and VIN
slows turn-ON of the power FET.
5
6
2
1
CLSEW
VOUT
Input
Switch output. The load being driven by MIC2005/2015 is connected to this
pin.
6
Output
3
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January 2008
Micrel
MIC2005/2015
Absolute Maximum Ratings(1)
Operating Ratings(2)
VIN, VOUT............................................................–0.3 to 6V Supply Voltage............................................. 2.5V to 5.5V
All other pins..................................................–0.3 to 5.5V Continuous Output Current Range .................... 0 to 2.1A
Power Dissipation.................................. Internally Limited
Continuous Output Current..................................... 2.25A
Maximum Junction Temperature........................... 150°C
Storage Temperature .............................. –65°C to 150°C
Ambient Temperature Range ....................–40°C to 85°C
Package Thermal Resistance (θJA)
SOT-23-5/6 ..........................................
MLF 2x2 mm............................................
MLF 2x2 mm θJC (5) ..................................
230°C/W
90°C/W
45°C/W
Electrical Characteristics
VIN = 5V, TAMBIENT = 25°C unless specified otherwise. Bold indicates –40°C to +85°C limits.
Symbol
Parameter
Conditions
Min
2.5
Typ
Max
5.5
Units
VIN
Switch Input Voltage
V
Switch = OFF,
IIN
Internal Supply Current
1
5
µA
ENABLE = 0V
Switch = ON, IOUT = 0
ENABLE = 1.5V
IIN
Internal Supply Current
Output Leakage Current
Power Switch Resistance
80
300
100
µA
µA
VIN = 5V, VOUT = 0 V, ENABLE
= 0
ILEAK
RDS(ON)
12
70
100
125
0.9
1.5
2.1
mΩ
mΩ
A
VIN = 5V, IOUT = 100 mA
ILIMIT
ILIMIT
ILIMIT
Current Limit: –0.5
Current Limit: –0.8
Current Limit: –1.2
VOUT = 0.8VIN to VOUT = 1V
VOUT = 0.8VIN to VOUT = 1V
VOUT = 0.8VIN, to VOUT = 1V
0.5
0.8
1.2
0.7
1.1
1.6
A
A
Secondary current limit
(Kickstart)
ILIMIT_2nd
MIC2015, VIN = 2.7V
2.2
4
6
A
VIN Rising
2.0
1.9
2.25
2.15
25
2.4
0.5
V
V
UVLOTHRESHOL
D
Under Voltage Lock Out
Threshold
V
IN Falling
VIL(max.)
V
VEN
ENABLE Input Voltage
VIH(min)
1.5
V
IEN
ENABLE Input Current
VEN = 0V to 5.0V
IOL = 10mA
TJ increasing
TJ decreasing
1
5
µA
V
VFAULT
Fault status Output Voltage
0.25
145
135
0.4
OTTHRESHOLD
Over-temperature Threshold
°C
4
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January 2008
Micrel
MIC2005/2015
AC Characteristics
Symbol
Parameter
Condition
Min
Typ
Max
Units
RL = 10Ω, CLOAD = 1µF,
tRISE
Output Turn-ON rise time
500
1000
1500
µs
V
OUT = 10% to 90%
Time from current limiting to
FAULT/ state change.
MIC2005
Time from IOUT continuously
exceeding primary current limit
condition to FAULT/ state
change. MIC2015
20
77
32
49
ms
ms
Delay before asserting or
releasing FAULT/
tD_FAULT
128
192
tD_LIMIT
tRESET
Delay before current limiting
MIC2015
77
77
128
128
192
192
ms
ms
Delay before resetting
Kickstart current limit delay,
tLIMIT
Out of current limit following a
current limit.
MIC2015
RL = 43Ω, CL = 120µF,
tON_DLY
Output Turn-ON Delay
Output Turn-OFF Delay
1000
1500
700
µs
µs
V
EN = 50% to VOUT = 90%
RL = 43Ω, CL = 120µF,
EN = 50% to VOUT = 90%
tOFF_DLY
V
ESD
Symbol
VESD_HB
Parameter
Condition
Min
Typ
Max
Units
kV
Electro Static Discharge
Voltage: Human Body Model
VOUT and GND
All other pins
All pins
± 4
± 2
kV
Electro Static Discharge
Voltage; Machine Model
± 200
V
ESD_MCHN
Machine Model
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.
5
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January 2008
Micrel
MIC2005/2015
Timing Diagrams
ENABLE
50%
50%
tON_DLY
tOFF_DLY
90%
VOUT
10%
Switching Delay Times
tRISE
tFALL
90%
90%
10%
10%
Rise and Fall Times
tRISE
90%
VOUT
10%
Output Rise Time
6
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January 2008
Micrel
MIC2005/2015
Typical Characteristics
Supply Current
Output Disabled
Switch Leakage Current - OFF
Supply Current
Output Enabled
1.00
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0
100
1.00
25°C
0.90
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0
-40°C
80
85°C
60
40
20
0
-40°C
85°C
25°C
2
3
4
5
6
7
2
3
4
5
6
-50 -30 -10 10 30 50 70 90
V
(V)
V
(V)
TEMPERATURE (°C)
ILIMIT vs. Temperature
(MIC20xx - 0.5)
IN
IN
ILIMIT vs. Temperature
(MIC20xx - 0.8)
ILIMIT vs. Temperature
(MIC20xx-1.2)
1.65
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
0.75
0.73
0.71
0.69
0.67
0.65
0.63
0.61
0.59
0.57
0.55
VIN = 2.5V
1.60
1.55
1.50
1.45
1.40
1.35
1.30
1.25
VIN = 3V
VIN = 5V
Note:
5V
Please note that the 3
3V
5V
3V
plots overlay each
2.5V
2.5V
-50 -30 -10 10 30 50 70 90
TEMPERATURE (°C)
-50 -30 -10 10 30 50 70 90
TEMPERATURE (°C)
-50 -30 -10 10 30 50 70 90
TEMPERATURE (°C)
RON vs.
RON vs.
ILIMIT vs.
Supply Voltage
Temperature
Temperature
100
1.4
120
2.5V
5V
1.2
1.0
0.8
0.6
0.4
0.2
0
100
80
60
40
20
0
3.3V
80
60
40
20
0
0.8A
0.5A
1.2A
2
2.5
3
3.5
V
4
(V)
4.5
5
5.5
-50 -30 -10 10 30 50 70 90
TEMPERATURE (°C)
-50 -30 -10 10 30 50 70 90
TEMPERATURE (°C)
IN
UVLO Threshold
vs. Temperature
2.3
2.25
2.2
V RISING
V FALLING
2.15
2.1
2.05
-50
0
50
100
150
TEMPERATURE (°C)
7
M9999-011708-A
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January 2008
Micrel
MIC2005/2015
Functional Characteristics
8
M9999-011708-A
(408) 944-0800
January 2008
Micrel
MIC2005/2015
9
M9999-011708-A
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January 2008
Micrel
MIC2005/2015
Functional Diagram
Under
Voltage
Detector
VIN
Current
Mirror FET
Power
FET
Control Logic
and Delay Timer
Gate Control
VOUT
GND
Thermal
Sensor
VREF
Slew Rate
Control
Current Limit
control Loop
Factory
adjusted
Figure 2 MIC2005/2015 Block Diagram
10
M9999-011708-A
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January 2008
Micrel
MIC2005/2015
duration of the Kickstart period. After this time the
MIC2015 reverts to its normal current limit. An example
of Kickstart operation is shown below.
Functional Description
VIN and VOUT
VIN is both the power supply connection for the internal
circuitry driving the switch and the input (Source
connection) of the power MOSFET switch. VOUT is the
Drain connection of the power MOSFET and supplies
power to the load. In a typical circuit, current flows from
VIN to VOUT toward the load. Since the switch is bi-
directional when enabled, if VOUT is greater than VIN,
current will flow from VOUT to VIN.
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 VOUT exceed VIN 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 CLOAD 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
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.
discharge of CLOAD
.
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.
B) RON of the power FET increases due to internal
heating (effect exaggerated for emphasis).
C) Kickstart period.
D) Current limiting initiated. FAULT/ goes LOW.
E) VOUT is non-zero (load is heavy, but not a dead short
where VOUT = 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.
Kickstart (MIC2015 only)
H) FAULT/ delay period followed by FAULT/ going
HIGH.
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.
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.
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
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January 2008
Micrel
MIC2005/2015
ENABLE
Slew Rate Control (Not present with SOT23-5 (M5))
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.
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.
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.
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.
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.
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.
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.
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MIC2005/2015
Application Information
ILIMIT vs. IOUT 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, VOUT drops
and the input to output voltage differential increases.
When VIN -VOUT exceeds 1V, IOUT drops below ILIMIT to
reduce the drain of fault current on the system’s power
supply and to limit internal heating of MIC2005/2015.
When measuring IOUT 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 VOUT is pulled
below VIN, with the test terminating when VOUT is 1V
below VIN. Observe that once ILIMIT is reached IOUT
remains constant throughout the remainder of the test.
In Figure 5 this test is repeated but with VIN - VOUT
exceeding 1V.
Figure 5. IOUT in Current Limiting for VOUT >1V
When VIN - VOUT > 1V, MIC2005/2015’s current limiting
circuitry responds by decreasing IOUT, as can be seen in
Figure 5. In this demonstration, VOUT is being controlled
and IOUT is the measured quantity. In real life
applications VOUT is determined in accordance with
Ohm’s law by the load and the limiting current.
This folding back of ILIMIT can be generalized by plotting
ILIMIT as a function of VOUT, as shown below. The slope
of VOUT between IOUT = 0 and IOUT = ILIMIT (where ILIMIT
=
1) is determined by RON of MIC2005/2015 and ILIMIT
.
Normalized Output Current
vs. Output Voltage (5V)
1.2
1.0
0.8
0.6
0.4
0.2
0
0
1
2
3
4
5
6
OUTPUT VOLTAGE (V)
Figure 6.
Figure 4. IOUT in Current Limiting for VOUT ≤1V
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MIC2005/2015
short circuit fault. For this reason, the upper limit on the
value of CSLEW is 4nF.
Normalized Output Current
vs. Output Voltage (2.5V)
1.2
1.0
0.8
0.6
0.4
0.2
0
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.
0
0.5 1.0 1.5 2.0 2.5 3.0
OUTPUT VOLTAGE (V)
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 IOUT to its programmed limit for as long as the
excessive load persists.
Figure 7.
CSLEW (Not present with SOT23-5 (M5))
The CSLEW 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, CSLEW, 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.
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 IOUT Æ 0. Upon cooling, if the
Figure 8 illustrates effect of CSLEW on turn-ON delay
and output rise time.
load is still present IOUT Æ ILIMIT, not IKICKSTART
.
Figure 8
CSLEW’s effect on ILIMIT
An unavoidable consequence of adding CSLEW
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
Figure 9. Kickstart
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MIC2005/2015
plots also assume a worst case RON of 140 mΩ 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.
Supply Filtering
A 0.1µF to 1µF bypass capacitor positioned close to the
VIN 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 VIN
(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.
Die Temperature vs. Iout for Tcase = 85°C
160
140
120
100
80
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.
60
Power Dissipation
40
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:
SOT-23
20
MLF
0
0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2
Iout - Amps
PD = RDS(ON)
×
(
IOUT
)
Figure 10. Die Temperature vs. IOUT
To relate this to junction temperature, the following
equation can be used:
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.
TJ = PD ×Rθ(J-A) + TA
Where: TJ = junction temperature,
TA = ambient temperature
Rθ(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 IOUT
assuming a constant case temperature of 85°C. The
15
M9999-011708-A
(408) 944-0800
January 2008
Micrel
MIC2005/2015
Package Information
2 Vias
0.3 mm diam.
to Ground Plane
1.4 mm
0.8 mm
Figure 11. Pad for thermal mounting to PCB
6-Pin SOT-23 (M6)
16
M9999-011708-A
(408) 944-0800
January 2008
Micrel
MIC2005/2015
Package Information (Cont.)
1.90 (0.075) REF
0.95 (0.037) REF
1.75 (0.069)3.00 (0.118)
1.50 (0.059)2.60 (0.102)
DIMENSIONS:
MM (INCH)
1.30 (0.051)
0.90 (0.035)
3.02 (0.119)
2.80 (0.110)
0.20 (0.00)8
0.09 (0.00)4
10°
0°
0.15 (0.006)
0.00 (0.000)
0.50 (0.020)
0.35 (0.014)
0.60 (0.024)
0.10 (0.004)
5-Pin SOT-23 (M5)
6 Pin 2mm × 2mm MLF (ML)
17
M9999-011708-A
(408) 944-0800
January 2008
Micrel
MIC2005/2015
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.
18
M9999-011708-A
(408) 944-0800
January 2008
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