MIC5216
500mA-Peak Output LDO Regulator
MM8 and Micrel Mini 8 are trademarks of Micrel, 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
March 2007
M9999-032307
General Description
The MIC5216 is an efficient linear voltage regulator with
high peak output current capability, very low dropout
voltage, and better than 1% output voltage accuracy.
Dropout is typically 10mV at light loads and less than
500mV at full load.
The MIC5216 is designed to provide a peak output current
for startup conditions where higher inrush current is
demanded. It features a 500mA peak output rating.
Continuous output current is limited only by package and
layout.
The MIC5216 has an internal undervoltage monitor with a
flag output. It also can be enabled or shutdown by a
CMOS or TTL compatible signal. When disabled, power
consumption drops nearly to zero. Dropout ground current
is minimized to help prolong battery life. Other key features
include reversed-battery protection, current limiting,
overtemperature shutdown, and low noise performance.
The MIC5216 is available in fixed output voltages in
space-saving SOT-23-5 and MM8™ 8-pin power MSOP
packages. For higher power requirements see the
MIC5209 or MIC5237.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Features
• Error Flag indicates undervoltage fault
• Guaranteed 500mA-peak output over the full operating
temperature range
• Low 500mV maximum dropout voltage at full load
• Extremely tight load and line regulation
• Tiny SOT-23-5 and MM8™ power MSOP-8 package
• Low-noise output
• Low temperature coefficient
• Current and thermal limiting
• Reversed input polarity protection
• CMOS/TTL-compatible enable/shutdown control
• Near-zero shutdown current
Applications
• Laptop, notebook, and palmtop computers
• Cellular telephones and battery-powered equipment
• Consumer and personal electronics
• PC Card V
CC
and V
PP
regulation and switching
• SMPS post-regulator/dc-to-dc modules
• High-efficiency linear power supplies
Typical Application
5V Low-Noise Regulator
3.3V Low-Noise Regu l ator
Micrel, Inc. MIC5216
March 2007
2 M9999-032307
Ordering Information
Part Number
Standard Marking Pb-Free Marking
Voltage Junction
Temp. Range Package
MIC5216-2.5BMM MIC5216-2.5YMM 2.5V –40° to +125°C 8-Pin MSOP
MIC5216-3.3BMM MIC5216-3.3YMM 3.3V –40° to +125°C 8-Pin MSOP
MIC5216-5.0BMM MIC5216-5.0YMM 5.0V –40° to +125°C 8-Pin MSOP
MIC5216-2.5BM5 LH25 MIC5216-2.5YM5 LH25 2.5V –40° to +125°C 5-Pin SOT-23
MIC5216-3.3BM5 LH33 MIC5216-3.3YM5 LH33 3.3V –40° to +125°C 5-Pin SOT-23
MIC5216-3.6BM5 LH36 MIC5216-3.6YM5 LH36 3.6V –40° to +125°C 5-Pin SOT-23
MIC5216-5.0BM5 LH50 MIC5216-5.0YM5 LH50 5.0V –40° to +125°C 5-Pin SOT-23
Micrel, Inc. MIC5216
March 2007
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Pin Configur ation
MIC5216-xxBMM/YMM
MM8™ MSOP-8
Fixed Voltages
MIC5216-xxBM5/YM5
SOT-23-5
Fixed Voltages
Pin Description
Pin Number
MSOP-8 Pin Number
SOT-23-5 Pin Name Pin Function
2 1 IN Supply Input
5–8 2 GND Ground: MSOP-8 pins 5 through 8 are internally connected.
3 5 OUT Regulator Output
1 3 EN
Enable (Input): CMOS compatible control input. Logic high = enable; logic
low or open = shutdown.
4 4 FLG
Error Flag (Output): Open-Collector output. Active low indicates an output
undervoltage condition.
Micrel, Inc. MIC5216
March 2007
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Absolute Maximum Ratings
Supply Input Voltage (V
IN
).............................. –20V to +20V
Power Dissipation (P
D
) .............................. Internally Limited
Junction Temperature (T
J
) ........................–40°C to +125°C
Lead Temperature (soldering, 5 sec.)........................ 260°C
Operating Ratings
Supply Input Voltage (V
IN
)................................. 2.5V to 12V
Enable Input Voltage (V
EN
)..................................... 0V to V
IN
Junction Temperature (T
J
) ........................ –40°C to +125°C
Thermal Resistance (θ
JA
).......................................... Note 1
Electrical Characteristics
V
IN
= V
OUT
+1V; C
OUT
= 4.7µF; I
OUT
= 100µA; T
J
= 25°C, bold values indicate –40°C < T
J
< +125°C, unless noted.
Symbol Parameter Condition Min Typ Max Units
V
O
Output Voltage Accuracy Variation from nominal V
OUT
–1
–2
1
2
%
%
∆V
O
/∆T Output Voltage Temperature
Coefficient
Note 2 40 ppm/°C
∆V
O
/V
O
Line Regulation V
IN
= V
OUT
+1V to 12V 0.009 0.05
0.1
%/V
%/V
∆V
O
/V
O
Load Regulation I
OUT
= 100µA to 150mA (Note 3) 0.05
0.5
0.7
%
%
V
IN
– V
O
Dropout Voltage, Note 4 I
OUT
= 100µA
I
OUT
= 50mA
I
OUT
= 150mA
I
OUT
= 500mA
10
115
165
300
60
80
175
250
300
400
500
600
mV
mV
mV
mV
mV
mV
mV
mV
I
GND
Ground Pin Current, Notes 5, 6
(per regulator)
V
EN
≥ 3.0V, I
OUT
= 100µA
V
EN
≥ 3.0V, I
OUT
= 50mA
V
EN
≥ 3.0V, I
OUT
= 150mA
V
EN
≥ 3.0V, I
OUT
= 500mA
80
350
1.8
8
130
170
650
900
2.5
3.0
20
25
µA
µA
µA
µA
mA
mA
mA
mA
I
GND
Quiescent Current, Note 6 V
EN
≤ 0.4V
V
EN
≤ 0.18V
0.05
0.10
3
8
µA
µA
PSRR Ripple Rejection Frequency = 120Hz 75 dB
I
LIMIT
Current Limit V
OUT
= 0V 700 1000 mA
∆V
O
/∆P
D
Thermal Regulation Note 7 0.05 %/W
e
no
Output Noise I
OUT
= 50mA, C
OUT
= 2.2µF 500 nV/√Hz
Micrel, Inc. MIC5216
March 2007
5 M9999-032307
Symbol Parameter Condition Min Typ Max Units
Enable Input
V
ENL
Enable Input Voltage V
EN
= logic low (regulator shutdown) 0.4
0.18
V
V
V
ENH
V
EN
= logic high (regulator enabled) 2.0 V
I
ENL
I
ENH
Enable Input Current V
ENL
≤ 0.4V
V
ENL
≤ 0.18V
V
ENH
≥ 2.0V
0.01
0.01
5
–1
–2
20
25
µA
µA
µA
µA
Error Flag Output
V
ERR
Flag Threshold Undervoltage condition (below nominal)
Note 8
–2 –6 –10 %
V
IL
Output Logic-Low Voltage I
L
= 1mA, undervoltage condition 0.2 0.4 V
I
FL
Flag Leakage Current Flag off, V
FLAG
= 0V to 12V –1 0.1 +1 µA
Notes:
1. Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating
the device outside of its operating ratings. The maximum allowable power dissipation is a function of the maximum junction temperature, T
J(max)
, the
junction-to-ambient thermal resistance, θ
JA
, and the ambient temperature, T
A
. The maximum allowable power dissipation at any ambient temperature
is calculated using: P
D(max)
= (T
J(max)
– T
A
) / θ
JA
. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the
regulator will go into thermal shutdown. See Table 1 and the “Thermal Considerations” section for details.
2. Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
3. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range from
100mA to 500mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
4. Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1V differential.
5. Ground pin current is the regulator quiescent current plus pass transistor base current. The total current drawn from the supply is the sum of the load
current plus the ground pin current.
6. V
EN
is the voltage externally applied to devices with the EN (enable) input pin.
7. Thermal regulation is defined as the change in output voltage at a time “t” after a change in power dissipation is applied, excluding load or line
regulation effects. Specifications are for a 500mA load pulse at V
IN
= 12V for t = 10ms.
8. The error flag comparator includes 3% hysteresis.
Micrel, Inc. MIC5216
March 2007
6 M9999-032307
Typical Characteristics
-100
-80
-60
-40
-20
0
1E+11E+21E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Pow er Suppl
y
Rejection Ratio
I
OUT
= 100µA
C
OUT
= 1µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M -100
-80
-60
-40
-20
0
1E+11E+21E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Pow er Suppl
y
Rejection Ratio
I
OUT
= 1mA
C
OUT
= 1µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M -100
-80
-60
-40
-20
0
1E+11E+21E+31E+41E+51E+61E+7
)Bd(RRSP
FREQUENCY (Hz)
Pow er Suppl
y
Rejection Ratio
I
OUT
= 100mA
C
OUT
= 1µF
V
IN
= 6V
V
OUT
= 5V
10 100 1k 10k 100k 1M 10M
0
10
20
30
40
50
60
0 0.1 0.2 0.3 0.4
)Bd(NOITCEJERELPPIR
VOLTAGE DROP (V)
Powe r Suppl y Ripp le Re je cti on
vs. Voltage Drop
I
OUT
= 100mA
10mA
1mA
C
OUT
= 1µF
500mA pending
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+31E+4 1E+5 1E+6 1E+
7
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10mA
1mA
100mA
10 100 1k 10k 100k 1M 10M
V
OUT
= 5V
C
OUT
= 10µF
electrolytic
500mA Pending
0.0001
0.001
0.01
0.1
1
10
1E+1 1E+2 1E+3 1E+4 1E+5 1E+6 1E+7
(ESIONµ/V )zH
FREQUENCY (Hz)
Noise Performance
10 100 1k 10k 100k 1M 10M
10mA, C
OUT
= 1µF
V
OUT
= 5V
500mA Pending
Micrel, Inc. MIC5216
March 2007
7 M9999-032307
Block Diagram
MIC5216 Fixed Regulator with External Components
Micrel, Inc. MIC5216
March 2007
8 M9999-032307
Application Information
The MIC5216 is designed for 150mA to 200mA output
current applications where a high current spike (500mA)
is needed for short, startup conditions. Basic application
of the device will be discussed initially followed by a
more detailed discussion of higher current applications.
Enable/Shutdown
Forcing EN (enable/shutdown) high (> 2V) enables the
regulator. EN is compatible with CMOS logic. If the
enable/shutdown feature is not required, connect EN to
IN (supply input). See Figure 5.
Input Capacitor
A 1µF capacitor should be placed from IN to GND if
there is more than 10 inches of wire between the input
and the ac filter capacitor or if a battery is used as the
input.
Output Capacitor
An output capacitor is required between OUT and GND
to prevent oscillation. 1µF minimum is recommended.
Larger values improve the regulator’s transient
response. The output capacitor value may be increased
without limit.
The output capacitor should have an ESR (equivalent
series resistance) of about 5Ω or less and a resonant
frequency above 1MHz. Ultralow-ESR capacitors could
cause oscillation and/or underdamped transient
response. Most tantalum or aluminum electrolytic
capacitors are adequate; film types will work, but more
expensive. Many aluminum electrolytics have
electrolytes that freeze at about –30°C, so solid
tantalums are recommended for operation below –25°C.
At lower values of output current, less output
capacitance is needed for stability. The capacitor can be
reduced to 0.47µF for current below 10mA or 0.33µF for
currents below 1mA.
No-Load Stability
The MIC5216 will remain stable and in regulation with no
load (other than the internal voltage divider) unlike many
other voltage regulators. This is especially important in
CMOS RAM keep-alive applications.
Error Flag Output
The error flag is an open-collector output and is active
(low) when an undervoltage of approximately 5% below
the nominal output voltage is detected. A pull-up resistor
from IN to FLAG is shown in all schematics.
If an error indication is not required, FLAG may be left
open and the pull-up resistor may be omitted.
Thermal Considerations
The MIC5216 is designed to provide 200mA of
continuous current in two very small profile packages.
Maximum power dissipation can be calculated based on
the output current and the voltage drop across the part.
To determine the maximum power dissipation of the
package, use the thermal resistance, junction-to-
ambient, of the device and the following basic equation.
(
)
JA
AJ(MAX)
D(MAX) θ
TT
P−
=
T
J(MAX)
is the maximum junction temperature of the die,
125°C, and T
A
is the ambient operating temperature. θ
JA
is layout dependent; table 1 shows examples of thermal
resistance, junction-to-ambient, for the MIC5216.
Package θ
JA
Recommended
Minimum Footprint θ
JA
1” Square
Copper Clad θ
JC
MM8™ (MM) 160°C/W 70°C/W 30°C/W
SOT-23-5 (M5) 220°C/W 170°C/W 130°C/W
Table 1. MIC5216 Thermal Resistance
The actual power dissipation of the regulator circuit can
be determined using one simple equation.
P
D
= (V
IN
– V
OUT
) I
OUT
+ V
IN
I
GND
Substituting P
D(MAX)
for P
D
and solving for the operating
conditions that are critical to the application will give the
maximum operating conditions for the regulator circuit.
For example, if we are operating the MIC5216-3.3BM5
at room temperature, with a minimum footprint layout,
we can determine the maximum input voltage for a set
output current.
(
)
C/W220
C25C125
P
D(MAX)
°
°−°
=
P
D(MAX)
= 455mW
The thermal resistance, junction-to-ambient, for the
minimum footprint is 220°C/W, taken from table 1. The
maximum power dissipation number cannot be
exceeded for proper operation of the device. Using the
output voltage of 3.3V, and an output current of 150mA,
we can determine the maximum input voltage. Ground
current, maximum of 3mA for 150mA of output current,
can be taken from the Electrical Characteristics section
of the data sheet.
455mW = (V
IN
– 3.3V) 150mA + V
IN
× 3mA
()
⎟
⎠
⎞
⎜
⎝
⎛
+
+
3mA150mA
150mA3.3V455mW
V
IN
Micrel, Inc. MIC5216
March 2007
9 M9999-032307
V
IN
= 6.2V
MAX
Therefore, a 3.3V application at 150mA of output current
can accept a maximum input voltage of 6.2V in a SOT-
23-5 package. For a full discussion of heat sinking and
thermal effects on voltage regulators, refer to the
Regulator Thermals section of Micrel’s
Designing with
Low-Dropout Voltage Regulators
handbook.
Peak Current Applications
The MIC5216 is designed for applications where high
start-up currents are demanded from space constrained
regulators. This device will deliver 500mA start-up
current from a SOT-23-5 or MM8 package, allowing high
power from a very low profile device. The MIC5216 can
subsequently provide output current that is only limited
by the thermal characteristics of the device. You can
obtain higher continuous currents from the device with
the proper design. This is easily proved with some
thermal calculations.
If we look at a specific example, it may be easier to
follow. The MIC5216 can be used to provide up to
500mA continuous output current. First, calculate the
maximum power dissipation of the device, as was done
in the thermal considerations section. Worst case
thermal resistance (θ
JA
= 220°C/W for the MIC5216-
x.xBM5), will be used for this example.
(
)
JA
AJ(MAX)
D(MAX)
θ
TT
P−
=
Assuming room temperature, we have a maximum
power dissipation number of
()
C/W220
C25C125
P
D(MAX)
°
°−°
=
P
D(MAX)
= 455mW
Then we can determine the maximum input voltage for a
five-volt regulator operating at 500mA, using worst case
ground current.
P
D(MAX)
= 455mW = (V
IN
– V
OUT
) I
OUT
+ V
IN
I
GND
I
OUT
= 500mA
V
OUT
= 5V
I
GND
=20mA
455mW = (V
IN
– 5V) 500mA + V
IN
× 20mA
2.995mW = 520mA × V
IN
5.683V
520mA
2.955W
V
IN(MAX)
==
Therefore, to be able to obtain a constant 500mA output
current from the 5216-5.0BM5 at room temperature, you
need extremely tight input-output voltage differential,
barely above the maximum dropout voltage for that
current rating.
You can run the part from larger supply voltages if the
proper precautions are taken. Varying the duty cycle
using the enable pin can increase the power dissipation
of the device by maintaining a lower average power
figure. This is ideal for applications where high current is
only needed in short bursts. Figure 1 shows the safe
operating regions for the MIC5216-x.xBM5 at three
different ambient temperatures and at different output
currents. The data used to determine this figure
assumed a minimum footprint PCB design for minimum
heat sinking. Figure 2 incorporates the same factors as
the first figure, but assumes a much better heat sink. A
1” square copper trace on the PC board reduces the
thermal resistance of the device. This improved thermal
resistance improves power dissipation and allows for a
larger safe operating region.
Figures 3 and 4 show, safe operating regions for the
MIC5216-x.xBMM, the power MSOP package part.
These graphs show three typical operating regions at
different temperatures. The lower the temperature, the
larger the operating region. The graphs were obtained in
a similar way to the graphs for the MIC5216-x.xBM5,
taking all factors into consideration and using two
different board layouts, minimum footprint and 1” square
copper PC board heat sink. (For further discussion of PC
board heat sink characteristics, refer to Application Hint
17, “Designing PC Board Heat Sinks”.
The information used to determine the safe operating
regions can be obtained in a similar manner to that used
in determining typical power dissipation, already
discussed. Determining the maximum power dissipation
based on the layout is the first step, this is done in the
same manner as in the previous two sections. Then, a
larger power dissipation number multiplied by a set
maximum duty cycle would give that maximum power
dissipation number for the layout. This is best shown
through an example. If the application calls for 5V at
500mA for short pulses, but the only supply voltage
available is 8V, then the duty cycle has to be adjusted to
determine an average power that does not exceed the
maximum power dissipation for the layout.
()
GNDINOUTOUTIND
I VI VV
100
%DC
Avg.P +−
⎟
⎠
⎞
⎜
⎝
⎛
=
()
20mA V 8500mA V58V
100
%DC
455mW ×+−
⎟
⎠
⎞
⎜
⎝
⎛
=
Micrel, Inc. MIC5216
March 2007
10 M9999-032307
1.66W
100
Cycle%Duty
455mW ⎟
⎠
⎞
⎜
⎝
⎛
=
⎟
⎠
⎞
⎜
⎝
⎛
=100
Cycle%Duty
274.0
% Duty Cycle Max = 27.4%
With an output current of 500mA and a three-volt drop
across the MIC5216-xxBMM, the maximum duty cycle is
27.4%.
Applications also call for a set nominal current output
with a greater amount of current needed for short
durations. This is a tricky situation, but it is easily
remedied. Calculate the average power dissipation for
each current section, then add the two numbers giving
the total power dissipation for the regulator. For
example, if the regulator is operating normally at 50mA,
but for 12.5% of the time it operates at 500mA output,
the total power dissipation of the part can be easily
determined. First, calculate the power dissipation of the
device at 50mA. We will use the MIC5216-3.3BM5 with
5V input voltage as our example.
P
D
× 50mA = (5V – 3.3V) × 50mA + 5V × 650µA
P
D
× 50mA = 173mW
However, this is continuous power dissipation, the actual
on-time for the device at 50mA is (100%-12.5%) or
87.5% of the time, or 87.5% duty cycle. Therefore, P
D
must be multiplied by the duty cycle to obtain the actual
average power dissipation at 50mA.
P
D
× 50mA = 0.875 × 173mW
P
D
× 50mA = 151mW
The power dissipation at 500mA must also be
calculated.
P
D
× 500mA = (5V – 3.3V) 500mA + 5V × 20mA
P
D
× 500mA = 950mW
This number must be multiplied by the duty cycle at
which it would be operating, 12.5%.
P
D
× = 0.125mA × 950mW
P
D
× = 119mW
a. 25
°
C Ambient b. 50
°
C Ambient c. 85
°
C Ambient
Figure 1. MIC5216-x.xBM5 (SOT-23-5) on Minimum Recomm ended Footprint
a. 25
°
C Ambient b. 50
°
C Ambient c. 85
°
C Ambient
Figure 2. MIC5216-x.xBM5 (SOT-23-5) on 1-inch
2
Copper Cladding
Micrel, Inc. MIC5216
March 2007
11 M9999-032307
a. 25
°
C Ambient b. 50
°
C Ambient c. 85
°
C Ambient
Figure 3. MIC5216-x.xBMM (MSOP-8) on Minimum Recommended Footprint
a. 25
°
C Ambient b. 50
°
C Ambient c. 85
°
C Ambient
Figure 4. MIC5216-x.xBMM (MSOP-8) on on 1-inch
2
Copper Cladding
The total power dissipation of the device under these
conditions is the sum of the two power dissipation
figures.
P
D(total)
= P
D
× 50mA + P
D
× 500mA
P
D(total)
= 151mW + 119mW
P
D(total)
= 270mW
The total power dissipation of the regulator is less than
the maximum power dissipation of the SOT-23-5
package at room temperature, on a minimum footprint
board and therefore would operate properly.
Multilayer boards with a ground plane, wide traces near
the pads, and large supply-bus lines will have better
thermal conductivity.
For additional heat sink characteristics, please refer to
Micrel Application Hint 17, “Designing P.C. Board Heat
Sinks”, included in Micrel’s Databook. For a full
discussion of heat sinking and thermal effects on voltage
regulators, refer to Regulator Thermals section of
Micrel’s Designing with Low-Dropout Voltage Regulators
handbook.
Fixed Regulator Circuits
MIC5216
IN OUT
GND 1µF
V
IN
V
OU
T
EN FLG
100k
Figure 5. Low-Noise Fixed Voltage Regulator
Figure 5 shows a basic MIC5216-x.xBMx fixed-voltage
regulator circuit. A 1µF minimum output capacitor is
required for basic fixed-voltage applications.
The flag output is an open-collector output and requires
a pull-up resistor to the input voltage. The flag indicates
an undervoltage condition on the output of the device.
Micrel, Inc. MIC5216
March 2007
12 M9999-032307
Package Information
8-Pin MSOP (MM)
SOT-23-5 (M5)
Micrel, Inc. MIC5216
March 2007
13 M9999-032307
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.
© 2000 Micrel, Incorporated.
