MICREL MIC5211

MIC5211
Micrel
MIC5211
Dual µCap 80mA LDO Regulator
Preliminary Information
General Description
Features
The MIC5211 is a dual µCap 80mA linear voltage regulator
with very low dropout voltage (typically 20mV at light loads),
very low ground current (225µA at 20mA output current), and
better than 3% initial accuracy. This dual device comes in the
miniature SOT-23-6 package, featuring independent logic
control inputs.
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The µCap regulator design is optimized to work with lowvalue, low-cost ceramic capacitors. The outputs typically
require only 0.1µF of output capacitance for stability.
Designed especially for hand-held, battery-powered devices,
ground current is minimized using Micrel’s proprietary Super
ßeta PNP™ technology to prolong battery life. When disabled, power consumption drops nearly to zero.
Key features include SOT-23-6 packaging, current limiting,
overtemperature shutdown, and protection against reversed
battery conditions.
Stable with low-value ceramic or tantalum capacitors
Independent logic controls
Low quiescent current
Low dropout voltage
Mixed voltages available
Tight load and line regulation
Low temperature coefficient
Current and thermal limiting
Reversed input polarity protection
Zero off-mode current
Dual regulator in tiny SOT-23 package
2.5V to 16V input range
Applications
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The MIC5211 is available in dual 1.8V, 2.5V, 2.7V, 2.8V,
3.0V, 3.3V, 3.6V, and 5.0V versions. Certain mixed voltages
are also available. Contact Micrel for other voltages.
Cellular telephones
Laptop, notebook, and palmtop computers
Battery-powered equipment
Bar code scanners
SMPS post regulator/dc-to-dc modules
High-efficiency linear power supplies
Ordering Information
Part Number
Marking
Voltage
Junction Temp. Range
Package
MIC5211-1.8BM6
LFBB
1.8V
0°C to +125°C
SOT-23-6
MIC5211-2.5BM6
LFCC
2.5V
–40°C to +125°C
SOT-23-6
MIC5211-2.7BM6
LFDD
2.7V
–40°C to +125°C
SOT-23-6
MIC5211-2.8BM6
LFEE
2.8V
–40°C to +125°C
SOT-23-6
MIC5211-3.0BM6
LFGG
3.0V
–40°C to +125°C
SOT-23-6
MIC5211-3.3BM6
LFLL
3.3V
–40°C to +125°C
SOT-23-6
MIC5211-3.6BM6
LFQQ
3.6V
–40°C to +125°C
SOT-23-6
MIC5211-5.0BM6
LFXX
5.0V
–40°C to +125°C
SOT-23-6
Dual-Voltage Regulators
Typical Application
MIC5211-1.8/2.5BM6
LFBC
1.8V/2.5V
0°C to +125°C
SOT-23-6
MIC5211-1.8/3.3BM6
LFBL
1.8V/3.3V
0°C to +125°C
SOT-23-6
MIC5211-2.5/3.3BM6
LFCL
2.5V/3.3V
–40°C to +125°C
SOT-23-6
MIC5211-3.3/5.0BM6
LFLX
3.3V/5.0V
–40°C to +125°C
SOT-23-6
Other voltages available. Contact Micrel for details.
VIN
MIC5211
Enable
Shutdown
Enable A
Enable
Shutdown
1
6
2
5
3
4
VOUTA
0.1µF
0.1µF
Enable B
VOUTB
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
November 2000
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MIC5211
MIC5211
Micrel
Pin Configuration
OUTA IN OUTB
6
Pin 1
Index
5
4
Part
Identification
LFxx
1
2
3
ENA GND ENB
Regulator A
Voltage Code
(VOUTA)
Voltage
Regulator B
Voltage Code
(VOUTB)
Code
1.8V
B
2.5V
C
2.7V
D
2.8V
E
3V
G
3.15V
H
3.3V
L
3.6V
Q
5V
X
Pin Description
Pin Number
Pin Name
1
ENA
Enable/Shutdown A (Input): CMOS compatible input. Logic high = enable,
logic low or open = shutdown.
2
GND
Ground
3
ENB
Enable/Shutdown B (Input): CMOS compatible input. Logic high = enable,
logic low or open = shutdown.
4
OUTB
5
IN
6
OUTA
MIC5211
Pin Function
Regulator Output B
Supply Input
Regulator Output A
2
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MIC5211
Micrel
Absolute Maximum Ratings (Note 1)
Operating Ratings (Note 2)
Supply Input Voltage (VIN) ............................ –20V to +20V
Enable Input Voltage (VEN) ........................... –20V to +20V
Power Dissipation (PD) ............................ Internally Limited
Storage Temperature Range ................... –60°C to +150°C
Lead Temperature (soldering, 5 sec.) ....................... 260°C
ESD, (Note 3) .....................................................................
Supply Input Voltage (VIN) ............................... 2.5V to 16V
Enable Input Voltage (VEN) ................................. 0V to 16V
Junction Temperature (TJ) (except 1.8V) . –40°C to +125°C
1.8V only .................................................. 0°C to +125°C
6-lead SOT-23-6 (θJA) .............................................. Note 4
Electrical Characteristics
VIN = VOUT + 1V; IL = 1mA; CL = 0.1µF, and VEN ≥ 2.0V; TJ = 25°C, bold values indicate –40°C to +125°C;
for one-half of dual MIC5211; unless noted.
Symbol
Parameter
Conditions
Min
VO
Output Voltage
Accuracy
variation from nominal VOUT
∆VO/∆T
Output Voltage
Temperature Coeffcient
Note 5
∆VO/VO
Line Regulation
∆VO/VO
VIN – VO
Typical
Max
Units
3
4
%
%
50
200
ppm/°C
VIN = VOUT +1V to 16V
0.008
0.3
0.5
%
%
Load Regulation
IL = 0.1mA to 50mA, Note 6
0.08
0.3
0.5
%
%
Dropout Voltage, Note 7
IL = 100µA
20
IL = 20mA
200
450
mV
IL = 50mA
250
500
mV
0.01
10
µA
–3
–4
mV
IQ
Quiescent Current
VEN ≤ 0.4V (shutdown)
IGND
Ground Pin Current
VEN ≥ 2.0V, IL = 100µA (active)
90
Note 8
IL = 20mA (active)
225
450
µA
IL = 50mA (active)
750
1200
µA
250
mA
ILIMIT
Current Limit
VOUT = 0V
140
∆VO/∆PD
Thermal Regulation
Note 9
0.05
µA
%/W
Enable Input
Enable Input Voltage Level
VIL
VIH
IIL
logic low (off)
logic high (on)
Enable Input Current
IIH
0.6
V
V
2.0
VIL ≤ 0.6V
0.01
1
µA
VIH ≥ 2.0V
3
50
µA
Note 1:
Exceeding the absolute maximum rating may damage the device.
Note 2:
The device is not guareented to function outside itsperating rating.
Note 3:
Devices are ESD sensitive. Handling precautions recommended.
Note 4:
The maximum allowable power dissipation at any TA (ambient temperature) is PD(max) = (TJ(max) – TA) / θJA. Exceeding the maximum
allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The θJA is 220°C/W for
the SOT-23-6 mounted on a printed circuit board.
Note 5:
Output voltage temperature coeffiecient is defined as the worst case voltage change divided by the total temperature range.
Note 6:
Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load
range from 0.1mA to 50mA. Change in output voltage due to heating effects are covered by thermal regulation specification.
Note 7:
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. For output voltages below 2.5V, dropout voltage is the input-to-output voltage differential with the minimum voltage being 2.5V.
Minimum input opertating voltage is 2.5V.
Note 8:
Ground pin current is the quiescent current per regulator plus pass transistor base current. The total current drawn from the supply is the sum
of the load current plus the ground pin current.
Note 9:
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 50mA load pulse at VIN = 16V for t = 10ms.
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MIC5211
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Micrel
Typical Characteristics
Dropout Voltage
vs. Output Current
4
CIN = 10µF
COUT = 1µF
300
IL = 50mA
200
100
0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
0.1
1
10
100
OUTPUT CURRENT (mA)
VIN = VOUT + 1V
0
IL = 50mA
1.0
0.5
2.5
CIN = 10µF
COUT = 1µF
2.0
1.5
1.0
0.5
0
CIN = 10µF
COUT = 1µF
50
100
150
200
OUTPUT CURRENT (mA)
0
1
2
3
4
5
6
SUPPLY VOLTAGE (V)
2.5
1
2
3
4
5
6
SUPPLY VOLTAGE (V)
7
1.5
1.0
IL = 50mA
0.5
IL = 100µA
7
Output Voltage
vs. Temperature
4.0
140
3.8
120
100
80
60
CIN = 10µF
COUT = 1µF
40
20
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
CIN = 10µF
COUT = 1µF
2.0
160
0
0
0.0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
Short Circuit Current
vs. Input Voltage
SHORT CIRCUIT CURRENT (mA)
OUTPUT VOLTAGE (V)
3.0
VOUT = 3.3V
IL = 100µA
Output Voltage
vs. Output Current
3.5
1
3.0
1.5
0.0
10 20 30 40 50 60 70 80
OUTPUT CURRENT (mA)
4.0
IL = 50mA
Ground Current
vs. Temperature
GROUND CURRENT (mA)
500
2
Ground Current
vs. Supply Voltage
OUTPUT VOLTAGE (V)
1000
IL = 100µA
3
0
2.0
1500
0.0
IL = 100µA
IL = 1mA
Ground Current
vs. Output Current
2000
OUTPUT VOLTAGE (V)
10
1
0.01
GROUND CURRENT (µA)
DROPOUT VOLTAGE (mV)
100
0
Dropout Characteristics
(MIC5211-3.3)
400
CIN = 10µF
COUT = 1µF
GROUND CURRENT (mA)
DROPOUT VOLTAGE (V)
1000
Dropout Voltage
vs. Temperature
7
3.6
CIN = 10µF
COUT = 1µF
3.4
3.2
3.0
2.8
2.6
3 DEVICES
HI / AVG / LO
CURVES APPLICABLE
AT 100µA AND 50mA
2.4
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
Short Circuit Current
vs. Temperature
OUTPUT CURRENT (mA)
200
180
160
CIN = 10µF
COUT = 1µF
140
120
100
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
MIC5211
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November 2000
MIC5211
Micrel
Load Transient
OUTPUT (mA) ∆ OUTPUT (mV)
0
COUT = 1µF
VIN = VOUT + 1
-200
100
-400
50
0
-50
-1 0
1
2 3 4 5
TIME (ms)
6
7
100
0
COUT = 10µF
VIN = VOUT + 1
-100
100
-200
50
0
-50
-5
8
0
3
2
CL = 1µF
IL = 1mA
1
0
-1
6
4
2
-0.2 0.0
1.0
0.2 0.4 0.6
TIME (ms)
FREQUENCY (Hz)
FREQUENCY (Hz)
5
60
20
0
IL = 50mA
CL = 1µF
VIN = VOUT + 1
1x106
40
100x103
1x106
100x103
0
10x103
20
IL = 1mA
CL = 1µF
VIN = VOUT + 1
1x103
40
80
10x103
RIPPLE VOLTAGE (dB)
60
100x100
1x106
100x103
10x103
1x103
IL = 100µA
CL = 1µF
VIN = VOUT + 1
100x100
1.0
100
80
10x100
RIPPLE VOLTAGE (dB)
60
November 2000
0.8
Ripple Voltage
vs. Frequency
100
80
10x100
4
1x103
0.8
6
Ripple Voltage
vs. Frequency
100
RIPPLE VOLTAGE (dB)
0
100x100
0.2 0.4 0.6
TIME (ms)
Ripple Voltage
vs. Frequency
0
CL = 11µF
IL = 1mA
1
8
-1
2
-0.2 0.0
20
20
2
INPUT (V)
INPUT (V)
8
-2
40
15
Line Transient
(MIC5211-3.3)
∆ OUTPUT (V)
∆ OUTPUT (V)
Line Transient
(MIC5211-3.3)
5
10
TIME (ms)
10x100
OUTPUT (mA) ∆ OUTPUT (mV)
Load Transient
200
FREQUENCY (Hz)
MIC5211
MIC5211
Micrel
Output Impedance
Enable Characteristics
(MIC5211-3.3)
IL = 100µA
10
IL = 1mA
1
2.0
0
-2
-2
Minimum Supply Voltage
vs. Temperature
0
2
4
6
TIME (µs)
8
5
4
3
2
1
0
4
-1
2
0
Enable Voltage
vs. Temperature
3.4
CIN = 10µF
COUT = 1µF
3.3
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
0.2 0.4 0.6
TIME (ms)
0.8
1.0
Enable Current
vs. Temperature
40
CIN = 10µF
COUT = 1µF
IL = 1mA
1.25
1.00
VOFF
VON
0.75
0.50
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
ENABLE CURRENT (µA)
IL = 1mA
VOUT = 3.3V
CL = 1µF
IL = 100µA
-2
-0.2 0.0
10
1.50
ENABLE VOLTAGE (mV)
MIN. SUPPLY VOLTAGE (V)
ENABLE (V)
ENABLE (V)
1x106
100x103
10x103
1x103
100x100
1x100
2
FREQUENCY (Hz)
3.5
CL = 1µF
IL = 100µA
1.0
0.0
4
-1.0
IL = 50mA
0.1
0.01
Enable Characteristics
(MIC5211-3.3)
4.0
3.0
OUTPUT (V)
OUTPUT (V)
100
10x100
OUTPUT IMPEDANCE (Ω)
1000
CIN = 10µF
COUT = 1µF
IL = 1mA
30
20
10
VEN = 5V
VEN = 2V
0
-60 -30 0 30 60 90 120 150
TEMPERATURE (°C)
VOUTA
(50mV/div.)
Crosstalk Characteristic
IOUTA
(50mA/div.)
VOUTB
(50mV/div.)
IOUTB = 100µA
COUTB = 0.47µF
COUTA = 0.47µF
TIME (25ms/div.)
MIC5211
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November 2000
MIC5211
Micrel
Applications Information
ENA and ENB (enable/shutdown) may be controlled separately. Forcing ENA/B high (>2V) enables the regulator. The
enable inputs typically draw only 15µA.
While the logic threshold is TTL/CMOS compatible, ENA/B
may be forced as high as 20V, independent of VIN. ENA/B
may be connected to the supply if the function is not required.
Input Capacitor
θ JA
125°C − 25°C
220°C/W
PD(max) =
PD(max) = 455mW
The MIC5211-3.0 can supply 3V to two different loads independently from the same supply voltage. If one of the regulators is supplying 50mA at 3V from an input voltage of 4V, the
total power dissipation in this portion of the regulator is:
A 0.1µF 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 when a battery is used as the input.
Output Capacitor
(
)
PD1 = VIN − VOUT IOUT + VIN ⋅ IGND
PD1 = (4V − 3V) 50mA + 4V ⋅ 0.85mA
Typical PNP based regulators require an output capacitor to
prevent oscillation. The MIC5211 is ultrastable, requiring only
0.1µF of output capacitance per regulator for stability. The
regulator is stable with all types of capacitors, including the
tiny, low-ESR ceramic chip capacitors. The output capacitor
value can be increased without limit to improve transient
response.
The capacitor should have a resonant frequency above
500kHz. Ceramic capacitors work, but some dielectrics have
poor temperature coefficients, which will affect the value of
the output capacitor over temperature. Tantalum capacitors
are much more stable over temperature, but typically are
larger and more expensive. Aluminum electrolytic capacitors
will also work, but they have electrolytes that freeze at about
–30°C. Tantalum or ceramic capacitors are recommended
for operation below –25°C.
No-Load Stability
PD1 = 53.4mW
Up to approximately 400mW can be dissipated by the remaining regulator (455mW – 53.4mW) before reaching the thermal shutdown temperature, allowing up to 50mA of current.
(
)
PD2 = VIN − VOUT IOUT + VIN ⋅ IGND
PD2 = (4V − 3V) 50mA + 4V ⋅ 0.85mA
PD2 = 53.4mW
The total power dissipation is:
PD1 + PD2 = 53.4mW + 53.4mW
PD1 + PD2 = 106.8mW
Therefore, with a supply voltage of 4V, both outputs can
operate safely at room temperature and full load (50mA).
The MIC5211 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.
Thermal Shutdown
VIN
MIC5211
OUTA
VOUTA
ENA OUTB
VOUTB
IN
ENB
Thermal shutdown is independent on both halves of the dual
MIC5211, however, an overtemperature condition in one half
may affect the other half because of proximity.
Thermal Considerations
When designing with a dual low-dropout regulator, both
sections must be considered for proper operation. The part is
designed with thermal shutdown, therefore, the maximum
junction temperature must not be exceeded. Since the dual
regulators share the same substrate, the total power dissipation must be considered to avoid thermal shutdown. Simple
thermal calculations based on the power dissipation of both
regulators will allow the user to determine the conditions for
proper operation.
GND
1µF 1µF
Figure 1. Thermal Conditions Circuit
In many applications, the ambient temperature is much
higher. By recalculating the maximum power dissipation at
70°C ambient, it can be determined if both outputs can supply
full load when powered by a 4V supply.
PD(max) =
PD(max) =
The maximum power dissipation for the total regulator system can be determined using the operating temperatures and
the thermal resistance of the package. In a minimum footprint
configuration, the SOT-23-6 junction-to-ambient thermal resistance (θJA) is 220°C/W. Since the maximum junction
temperature for this device is 125°C, at an operating temperature of 25°C the maximum power dissipation is:
November 2000
TJ(max) − TA
PD(max) =
Enable/Shutdown
TJ(max) − TA
θ JA
125°C − 70°C
220°C/W
PD(max) = 250mW
At 70°C, the device can provide 250mW of power dissipation,
suitable for the above application.
When using supply voltages higher than 4V, do not exceed
the maximum power dissipation for the device. If the device
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MIC5211
MIC5211
Micrel
considerations must be taken to ensure proper functionality
of the part. The input voltage must be high enough for the 5V
section to operate correctly, this will ensure the 3.3V section
proper operation as well.
Both regulators live off of the same input voltage, therefore
the amount of output current each regulator supplies may be
limited thermally. The maximum power the MIC5211 can
dissipate at room temperature is 455mW, as shown in the
“Thermal Considerations” section. If we assume 6V input
voltage and 50mA of output current for the 3.3V section of the
regulator, then the amount of output current the 5V section
can provide can be calculated based on the power dissipation.
is operating from a 7.2V-nominal two-cell lithium-ion battery
and both regulators are dropping the voltage to 3.0V, then
output current will be limited at higher ambient temperatures.
For example, at 70°C ambient the first regulator can supply
3.0V at 50mA output from a 7.2V supply; however, the
second regulator will have limitations on output current to
avoid thermal shutdown. The dissipation of the first regulator
is:
PD1 = (7.2V − 3V) 50mA + 7.2V ⋅ 0.85mA
PD1 = 216mW
Since maximum power dissipation for the dual regulator is
250mW at 70°C, the second regulator can only dissipate up
to 34mW without going into thermal shutdown. The amount
of current the second regulator can supply is:
PD = (VGND – VOUT) IOUT + VGND · IGND
PD(3.3V) = (6V – 3.3V) 50mA + 6V · 0.85mA
PD(3.3V) = 140.1mW
PD2(max) = 34mW
PD(max) = 455mW
PD(max) – PD(3.3V) = PD(5V)
(7.2V − 3V) IOUT2(max) = 34mW
4.2V ⋅ IOUT2(max) = 34mW
PD(5V) = 455mW – 140.1mW
PD(5V) = 314.9mW
IOUT2(max) = 8mA
The second regulator can provide up to 8mA output current,
suitable for the keep-alive circuitry often required in handheld applications.
Based on the power dissipation allowed for the 5V section,
the amount of output current it can source is easily calculated.
PD(5V) = 314.9mW
Refer to Application Hint 17 for heat sink requirements when
higher power dissipation capability is needed. Refer to Designing with Low Dropout Voltage Regulators for a more
thorough discussion of regulator thermal characteristics.
Dual-Voltage Considerations
314.9mW = (6V – 5V) IMAX – 6V · IGND
(IGND typically adds less than 5% to the total power dissipation and in this case can be ignored)
314.9mW = (6V – 5V) IMAX
IMAX = 314.9mA
IMAX exceeds the maximum current rating of the device.
Therefore, for this condition, the MIC5211 can supply 50mA
of output current from each section of the regulator.
For configurations where two different voltages are needed in
the system, the MIC5211 has the option of having two
independent output voltages from the same input. For example, a 3.3V rail and a 5.0V rail can be supplied from the
MIC5211 for systems that require both voltages. Important
MIC5211
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November 2000
MIC5211
Micrel
Package Information
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)
3.00 (0.118)
2.80 (0.110)
0.50 (0.020)
0.35 (0.014)
1.30 (0.051)
0.90 (0.035)
0.20 (0.008)
0.09 (0.004)
10°
0°
0.15 (0.006)
0.00 (0.000)
0.60 (0.024)
0.10 (0.004)
SOT-23-6 (M6)
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MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131
TEL
+ 1 (408) 944-0800
FAX
+ 1 (408) 944-0970
WEB
USA
http://www.micrel.com
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.
© 2000 Micrel Incorporated
MIC5211
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