Micrel MIC5235-3.3BM5 Ultra-low quiescent current, 150ma î¼cap ldo regulator Datasheet

MIC5235
Ultra-Low Quiescent Current, 150mA
µCap LDO Regulator
General Description
Features
The MIC5235 is a 150mA highly accurate, low dropout
regulator with high input voltage and ultra-low ground
current. This combination of high voltage and low ground
current makes the MIC5235 ideal for USB and portable
electronics applications, using 1-cell, 2-cell or 3-cell Li-Ion
battery inputs.
A µCap LDO design, the MIC5235 is stable with either
ceramic or tantalum output capacitor. It only requires a
2.2µF capacitor for stability.
Features of the MIC5235 includes enable input, thermal
shutdown, current limit, reverse battery protection, and
reverse leakage protection.
Available in fixed and adjustable output voltage versions,
®
the MIC5235 is offered in the IttyBitty SOT-23-5 package
with a junction temperature range of –40°C to +125°C.
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•
•
•
•
•
•
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Wide input voltage range: 2.3V to 24V
Ultra low ground current: 18µA
Low dropout voltage: 310mV at 150mA
High output accuracy: ±2.0% over temperature
µCap: stable with ceramic or tantalum capacitors
Excellent line and load regulation specifications
Zero shutdown current
Reverse battery protection
Reverse leakage protection
Thermal shutdown and current limit protection
IttyBitty® SOT-23-5 package
Adjustable output from 1.24V-20V
Applications
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USB power supply
Cellular phones
Keep-alive supply in notebook and portable computers
Logic supply for high-voltage batteries
Automotive electronics
Battery powered systems
Typical Application
MIC5235BM5
VIN
1
5
R1
2
CIN=1.0µF
3
EN
VOUT=1.8V
4
R2
COUT=2.2µF
ceramic
IGND=18µA
GROUND CURRENT (µA)
40
35
30
IOUT = 1mA
25
20
15
10
49
Ultra-Low Current Adjustable Regulator Application
IOUT = 100µA
IOUT = 10µA
14
19
INPUT VOLTAGE (V)
24
Ground Current vs. Input Voltage
IttyBitty is a registered trademark 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
May 2008
M9999-051508
Micrel, Inc.
MIC5235
Ordering Information
Part Number
Marking Codes
Junction
Temp. Range
Package
Standard
Pb-Free
Standard
Pb-Free*
Voltage**
MIC5235-1.5BM5
MIC5235-1.5YM5
L215
L215
1.5V
–40° to +125°C
5-Pin SOT-23
MIC5235-1.8BM5
MIC5235-1.8YM5
L218
L218
1.8V
–40° to +125°C
5-Pin SOT-23
MIC5235-2.5BM5
MIC5235-2.5YM5
L225
L225
2.5V
–40° to +125°C
5-Pin SOT-23
MIC5235-2.7BM5
MIC5235-2.7YM5
L227
L227
2.7V
–40° to +125°C
5-Pin SOT-23
MIC5235-3.0BM5
MIC5235-3.0YM5
L230
L230
3.0V
–40° to +125°C
5-Pin SOT-23
MIC5235-3.3BM5
MIC5235-3.3YM5
L233
L233
3.3V
–40° to +125°C
5-Pin SOT-23
MIC5235-5.0BM5
MIC5235-5.0YM5
L250
L250
5.0V
–40° to +125°C
5-Pin SOT-23
MIC5235BM5
MIC5235YM5
L2AA
L2AA
Adj.
–40° to +125°C
5-Pin SOT-23
* Under bar symbol (_) may not be to scale.
** Contact factory regarding availability for voltages not listed.
Pin Configuration
EN GND IN
3
2
EN GND IN
1
3
L2xx
L2xx
2
1
L2xx
L2xx
4
5
4
5
NC
OUT
ADJ
OUT
SOT-23-5 (Fixed)
SOT-23-5 (Adjustable)
Pin Description
Pin Number
Pin Name
Pin Function
1
IN
Supply Input.
2
GND
3
EN
4
NC (fixed)
No Connect.
ADJ (adj.)
Adjust (Input): Feedback input. Connect to resistive voltage-divider network.
5
May 2008
Ground.
OUT
Enable (Input): Logic low = shutdown; logic high = enable.
Regulator Output.
2
M9999-051508
Micrel, Inc.
MIC5235
Absolute Maximum Ratings(1)
Operating Ratings(2)
Input Supply Voltage ........................................ –20V to 38V
Enable Input Voltage....................................... –0.3V to 38V
Power Dissipation .....................................Internally Limited
Junction Temperature ...............................–40°C to +125°C
Storage Temperature ................................–65°C to +150°C
ESD Rating(3)
Input Supply Voltage ......................................... 2.3V to 24V
Enable Input Voltage............................................ 0V to 24V
Junction Thermal....................................... –40°C to +125°C
Package Thermal Resistance
SOT-23-5 (θJA).................................................235°C/W
Electrical Characteristics(4)
TA = 25°C with VIN = VOUT + 1V; IOUT = 100µA, Bold values indicate –40°C<TJ<+125°C; unless otherwise specified.
Parameter
Condition
Min
Output Voltage Accuracy
Variation from nominal VOUT
–1.0
–2.0
Line Regulation
VIN = VOUT + 1V to 24V
0.04
Load Regulation
Load = 100µA to 150mA
0.25
Dropout Voltage
IOUT = 100µA
IOUT = 50mA
50
230
IOUT = 100mA
270
IOUT = 150mA
310
Max
Units
+1.0
+2.0
%
%
%
1
%
300
400
400
450
450
500
mV
mV
mV
mV
mV
mV
mV
1.24
1.25
V
IOUT = 100µA
18
IOUT = 50mA
IOUT = 100mA
IOUT = 150mA
0.35
1
2
30
35
0.7
2
4
µA
µA
mA
mA
mA
Reference Voltage
Ground Current
Typ
1.22
Ground Current in Shutdown
VEN ≤ 0.6V; VIN = 24V
0.1
1
µA
Short Circuit Current
VOUT = 0V
350
500
mA
Output Leakage,
Reverse Polarity Input
Load = 500Ω; VIN = –15V
–0.1
µA
Enable Input
0.6
Input Low Voltage
Regulator OFF
Input High Voltage
Regulator ON
2.0
Enable Input Current
VEN = 0.6V; Regulator OFF
VEN = 2.0V; Regulator ON
VEN = 24V; Regulator ON
–1.0
V
V
0.01
0.1
0.5
1.0
1.0
2.5
µA
µA
µA
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.
May 2008
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Micrel, Inc.
MIC5235
Typical Characteristics
70
350
60
DROPOUT VOLTAGE (mV)
ILOAD = 150mA
40
30
20
10
100
50
ILOAD = 150mA
1
0.5
2000
1500
1000
500
0
02
GROUND CURRENT (µA)
ILOAD = 10mA
70
65
60
55
50
45
-40 -20 02
04 06 08 0 100 120
700
680
580
560
540
520
500
-40 -20 02
GROUND CURRENT (µA)
GROUND CURRENT (µA)
80
70
60
IOUT = 100µA
30
May 2008
04 06 08 0 100 120
TEMPERATURE (°C)
IOUT = 10mA
IOUT = 10µA
2
2.5
3
3.5
INPUT VOLTAGE (V)
ILOAD = 75mA
4
2.4
2.2
2
1.8
26
24
IOUT =150mA
IOUT = 75mA
0.6
2
2.5
3
3.5
INPUT VOLTAGE (V)
4
4
VIN = 24V
VIN = 12V
22
20
18
VIN = 4V
16
14
12
100 200 300 400 500
OUTPUT CURRENT (µA)
Ground Pin Current
vs. Temperature
2.5
2.4
ILOAD = 150mA
2.3
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
-40 -20 02 04 06 08 0 100 120
TEMPERATURE (°C)
Ground Pin Current
vs. Input Voltage
40
1.4
1.2
0.4
1.5
30
28
Ground Pin Current
vs. Input Voltage
1.6
1
0.8
Ground Pin Current
vs. Output Current
10
0
Ground Pin Current
vs. Temperature
620
600
Ground Pin Current
vs. Input Voltage
0
1.5
100
50
0
-40 -20 02 04 06 08 0 100 120
TEMPERATURE (°C)
04 06 08 0 100 120 140 160
OUTPUT CURRENT (mA)
660
640
TEMPERATURE (°C)
50 IOUT = 1mA
40
VIN = 4V
2500
Ground Pin Current
vs. Temperature
75
20
10
250
200
150
3000
ILOAD = 100µA
1.5
100
90
04 06 08 0 100 120 140 160
OUTPUT CURRENT (mA)
350
300
Ground Pin Current
vs. Output Current
0
0 0.5 1 1.5 2 2.5 3 3.5 4
INPUT VOLTAGE (V)
GROUND CURRENT (µA)
150
Dropout
Characteristics
2
40
200
0
02
1000
2.5 ILOAD = 75mA
80
250
500
450 IOUT = 150mA
400
GROUND CURRENT (µA)
3
300
GROUND CURRENT (mA)
OUTPUT VOLTAGE (V)
3.5
0.1
11
0
100
FREQUENCY (kHz)
GROUND CURRENT (µA)
0
0.01
Dropout Voltage
vs. Temperature
GROUND CURRENT (µA)
PSRR (dB)
50
Dropout Voltage
vs. Output Current
DROPOUT VOLTAGE (mV)
Power Supply
Rejection Ratio
35
30
IOUT = 1mA
25
IOUT = 100µA
20
15
10
49
IOUT = 10µA
14
19
INPUT VOLTAGE (V)
24
M9999-051508
Micrel, Inc.
MIC5235
Typical Characteristics (continued)
100
80
60
40
20
0
-20
VEN = 5V
RLOAD = 30
-10
0
SUPPLY VOLTAGE (V)
10
3.04
3.03
Output Voltage
vs. Temperature
SHORT CIRCUIT CURRENT (mA)
3.05
OUTPUT VOLTAGE (V)
INPUT CURRENT (mA)
120
Input Current
vs. Supply Voltage
ILOAD = 100 µA
3.02
3.01
3
2.99
2.98
2.97
2.96
2.95
-40 -20 02 04 06 08 0 100 120
TEMPERATURE (°C)
400
Short Circuit Current
vs. Temperature
350
300
250
200
150
100
50
VIN = 4V
0
-40 -20 02 04 06 08 0 100 120
TEMPERATURE (°C)
150mA
0mA
VIN = 4V
VOUT = 3V
COUT = 4.7µF ceramic
May 2008
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M9999-051508
Micrel, Inc.
MIC5235
Functional Diagram
OUT
IN
EN
ENABLE
1.24V
VREF
GND
Block Diagram – Fixed Output Voltage
OUT
IN
EN
ENABLE
R1
1.24V
VREF
ADJ
R2
GND
Block Diagram – Adjustable Output Voltage
May 2008
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M9999-051508
Micrel, Inc.
MIC5235
Application Information
⎛ TJ(MAX) − TA
PD(MAX) = ⎜⎜
θ JA
⎝
Enable/Shutdown
The MIC5235 comes with an active-high enable pin that
allows the regulator to be disabled. Forcing the enable
pin low disables the regulator and sends it into a “zero”
off-mode-current state. In this state, current consumed
by the regulator goes nearly to zero. Forcing the enable
pin high enables the output voltage.
TJ(MAX) is the maximum junction temperature of the die,
125°C, and TA is the ambient operating temperature. θJA
is layout dependent; Table 1 shows examples of the
junction-to-ambient thermal resistance for the MIC5235.
Input Capacitor
The MIC5235 has high input voltage capability up to
24V. The input capacitor must be rated to sustain
voltages that may be used on the input. An input
capacitor may be required when the device is not near
the source power supply or when supplied by a battery.
Small, surface mount, ceramic capacitors can be used
for bypassing. Larger values may be required if the
source supply has high ripple.
Package
θJA Recommended
Minimum Footprint
SOT-23-5
235°C
Table 1. SOT-23-5 Thermal Resistance
The actual power dissipation of the regulator circuit can
be determined using the equation:
PD = (VIN – VOUT)IOUT + VINIGND
Substituting PD(MAX) for PD and solving for the operating
conditions that are critical to the application will give the
maximum operating conditions for the regulator circuit.
For example, when operating the MIC5235-3.0BM5 at
50°C with a minimum footprint layout, the maximum
input voltage for a set output current can be determined
as follows:
Output Capacitor
The MIC5235 requires an output capacitor for stability.
The design requires 2.2µF or greater on the output to
maintain stability. The design is optimized for use with
low-ESR ceramic chip capacitors. High ESR capacitors
may cause high frequency oscillation. The maximum
recommended ESR is 3Ω. The output capacitor can be
increased without limit. Larger valued capacitors help to
improve transient response.
X7R/X5R dielectric-type ceramic capacitors are
recommended
because
of
their
temperature
performance. X7R-type capacitors change capacitance
by 15% over their operating temperature range and are
the most stable type of ceramic capacitors. Z5U and
Y5V dielectric capacitors change value by as much as
50% and 60% respectively over their operating
temperature ranges. To use a ceramic chip capacitor
with Y5V dielectric, the value must be much higher than
a X7R ceramic capacitor to ensure the same minimum
capacitance over the equivalent operating temperature
range.
⎛ 125°C − 50°C ⎞
PD(MAX) = ⎜
⎟
⎝ 235°C/W ⎠
PD(MAX) = 319mW
The junction-to-ambient (θJA) thermal resistance for the
minimum footprint is 235°C/W, from Table 1. It is
important that the maximum power dissipation not be
exceeded to ensure proper operation. Since the
MIC5235 was designed to operate with high input
voltages, careful consideration must be given so as not
to overheat the device. With very high input-to-output
voltage differentials, the output current is limited by the
total power dissipation. Total power dissipation is
calculated using the following equation:
PD = (VIN – VOUT)IOUT + VIN × IGND
Due to the potential for input voltages up to 24V, ground
current must be taken into consideration. If we know the
maximum load current, we can solve for the maximum
input voltage using the maximum power dissipation
calculated for a 50°C ambient, 319mV.
PD(MAX) = (VIN – VOUT)IOUT + VIN x IGND
319mW = (VIN – 3V)150mA + VIN x 2.8mA
Ground pin current is estimated using the typical
characteristics of the device.
769mW = VIN (152.8mA)
VIN = 5.03V
For higher current outputs only a lower input voltage will
work for higher ambient temperatures.
Assuming a lower output current of 20mA, the maximum
input voltage can be recalculated:
No-Load Stability
The MIC5235 will remain stable and in regulation with no
load unlike many other voltage regulators. This is
especially important in CMOS RAM keep-alive
applications.
Thermal Considerations
The MIC5235 is designed to provide 150mA of
continuous current in a very small package. 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 junction-to-ambient thermal resistance
of the device and the following basic equation:
May 2008
⎞
⎟
⎟
⎠
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M9999-051508
Micrel, Inc.
MIC5235
Where VREF = 1.24V.
Feedback resistor R2 should be no larger than 300kΩ.
319mW = (VIN – 3V)20mA + VIN x 0.2mA
379mW = VIN x 20.2mA
VIN = 18.8V
Maximum input voltage for a 20mA load current at 50°C
ambient temperature is 18.8V, utilizing virtually the entire
operating voltage range of the device.
VIN
VOUT
May 2008
IN
OUT
EN
ADJ.
VOUT
R1
1.0µF
Adjustable Regulator Application
The MIC5235BM5 can be adjusted from 1.24V to 20V by
using two external resistors (Figure 1). The resistors set
the output voltage based on the following equation:
⎛ ⎛R
= VREF ⎜1 + ⎜⎜ 1
⎜
⎝ ⎝ R2
MIC5235BM5
GND
2.2µF
R2
Figure 1. Adjustable Voltage Application
⎞⎞
⎟⎟ ⎟
⎟
⎠⎠
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M9999-051508
Micrel, Inc.
MIC5235
Package Information
SOT-23-5 (M5)
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.
© 2003 Micrel, Incorporated.
May 2008
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