Datasheet MIC2205 Datasheet (Micrel)

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MIC2205

2MHz PWM Synchronous Buck

Regulator with LDO Standby Mode

General Description

The Micrel MIC2205 is a high efficiency 2MHz PWM
synchronous buck (step-down) regulator that
features a LOWQ™ LDO standby mode that draws
only 18µA of quiescent current. The MIC2205
allows an ultra-low noise, small size, and high
efficiency solution for portable power applications.

In PWM mode, the MIC2205 operates with a
constant frequency 2MHz PWM control. Under light
load conditions, such as in system sleep or standby
modes, the PWM switching operation can be
disabled to reduce switching losses. In this light
load LOWQ™ mode, the LDO maintains the output
voltage and draws only 18µA of quiescent current.
The LDO mode of operation saves battery life while
not introducing spurious noise and high ripple as
experienced with pulse skipping or bursting mode
regulators.

The MIC2205 operates from 2.7V to 5.5V input and
features internal power MOSFETs that can supply
up to 600mA output current in PWM mode. It can
operate with a maximum duty cycle of 100% for use
in low-dropout conditions.

The MIC2205 is available in the 3mm x 3mm MLF­10L package with a junction operating range from
–40°C to +125°C.

Data sheets and support documentation can be
found on Micrel’s web site at www.micrel.com.

____________________________________________________________________________________________________

Features

• 2.7 to 5.5V supply voltage

• Light load LOWQ™ LDO mode

18µA quiescent current
Low noise, 75µVrms

• 2MHz PWM mode
Output current to 600mA
>95% efficiency
100% maximum duty cycle

• Adjustable output voltage option down to 1V
Fixed output voltage options available

• Ultra-fast transient response

• Stable with 1µF ceramic output capacitor

• Fully integrated MOSFET switches

• Micropower shutdown

• Thermal shutdown and current limit protection

• Pb-free 3mm x 3mm MLF-10L package

• –40°C to +125°C junction temperature range

Applications

• Cellular phones

• PDAs

• USB peripherals

Typical Application

2.7V to 5.5V

V

GND

IN

C1

1µF

LowQ

C2

0.1µF

MIC2205

8

VIN

4

AVINSWLDO

6

EN

7

LOWQ

3

BIAS

PGND

AGND

10 1

FB

Adjustable Output Buck Regulator with LOWQ™ Mode

2.2µH

9

2

R1
100k

5

R2
125k

C3
100pF

V

C4

2.2µF

GND

OUT

1.8V

Efficiency

100

95
90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

0 100 200 300 400 500 600

OUT

VIN=3V

VIN=3.6V

VIN=4.2V

OUTPUT CURRENT (mA)

Patent Pending
LOWQ is a trademark of Micrel, Inc

Micrel, Inc • 2180 Fortune Drive • San Jose, Ca 95131 • USA • tel [phone] • fax [phone] • http://www.micrel.com

April 2005

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Micrel, Inc. MIC2205

A

Ordering Information

Part Number Output Voltage

MIC2205-1.3YML 1.3V –40° to +125°C 3x3 MLF-10L Pb-free
MIC2205-1.38YML 1.38V –40° to +125°C 3x3 MLF-10L Pb-free
MIC2205-1.5YML 1.5V –40° to +125°C 3x3 MLF-10L Pb-free
MIC2205-1.58YML 1.58V –40° to +125°C 3x3 MLF-10L Pb-free
MIC2205-1.8YML 1.8V –40° to +125°C 3x3 MLF-10L Pb-free
MIC2205-1.85YML 1.85V –40° to +125°C 3x3 MLF-10L Pb-free
MIC2205YML Adj. –40° to +125°C 3x3 MLF-10L Pb-free

Note:

1. Other Voltage options available. Contact Micrel for details.

(1)

Junction Temp. Range Package Lead Finish

Pin Configuration

PGND

GND

LDO
BIAS

1
2
3

10

SW

9

VIN

8

Pin Description

Pin Number Pin Name Pin Function

1 AGND Analog (signal) Ground.
2 LDO LDO Output (Output): Connect to V
3 BIAS

4 AVIN

5 FB

6 EN

7

8 VIN Supply Voltage (Input): Supply voltage for the internal switches and drivers.
9 SW Switch (Output): Internal power MOSFET output switches.

10 PGND Power Ground.

EP GND Ground, backside pad.

_____

LOWQ

LOWQ

AVIN

4

FB EN

5

EP

7
6

3mm x 3mm MLF-10L (ML)

for LDO mode operation.

OUT

Internal circuit bias supply. Must be de-coupled to signal ground with a 0.1µF
capacitor and should not be loaded.

Analog Supply Voltage (Input): Supply voltage for the analog control circuitry and
LDO input power. Requires bypass capacitor to GND.

Feedback. Input to the error amplifier. For the Adjustable option, connect to the
external resistor divider network to set the output voltage. For fixed output
voltage options, connect to V
voltage.

Enable (Input). Logic low will shut down the device, reducing the quiescent
current to less than 5µA.

Enable LDO Mode (Input): Logic low enables the internal LDO and disables the
PWM operation. Logic high enables the PWM mode and disables the LDO
mode.

and an internal resistor network sets the output

OUT

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Absolute Maximum Ratings

(1)

Supply Voltage (VIN) ............................................ +6V

Output Switch Voltage (V
Output Switch Current (I
Logic Input Voltage (V
Storage Temperature (T
ESD Rating

(3)

....................................................... 3kV

Electrical Characteristics

) ............................... +6V

SW

)................................... 2A

SW

EN,VLOWQ

).............. -0.3V to VIN

)................ -60°C to +150°C

s

(4)

Operating Ratings

Supply Voltage (VIN)............................+2.7V to +5.5V

Logic Input Voltage (V
Junction Temperature (T
Junction Thermal Resistance
3x3 MLF-10L (θ

(2)

EN,VLOWQ

)...................................60°C/W

JA

) ..............-0.3V to VIN

)..............–40°C to +125°C

J

VIN = VEN = V

=3.6V; L = 2.2µH; C

LOWQ

= 2.2µF; TA = 25°C, unless noted. Bold values indicate –40°C< TJ < +125°C

OUT

Parameter Condition Min Typ Max Units

Supply Voltage Range
Under-Voltage Lockout

(turn-on) 2.45 2.55 2.65 V

2.7

5.5

V

Threshold
UVLO Hysteresis 100 mV
Quiescent Current, PWM

= 0.9 * V

V

FB

(not switching) 690

NOM

900

µA

mode
Quiescent Current, LDO

V

LOWQ

= 0V;I

= 0mA 16

OUT

29

µA

mode
Shutdown Current VEN = 0V 0.01
[Adjustable] Feedback

Voltage

± 1%
± 2% (over temperature)

[Fixed Output] Voltages Nominal V

tolerance

OUT

0.99

0.98

-1

-2

1

5

1.01

1.02

+1

+2

µA

V

%

FB pin input current 1 nA
Current Limit in PWM Mode VFB = 0.9 * V
Output Voltage Line

Regulation
Output Voltage Load

V

> 2V; VIN = V

OUT

< 2V; VIN = 2.7V to 5.5V; I

V

OUT

20mA < I

LOAD

NOM

+300mV to 5.5V; I

OUT

LOAD

LOAD

= 100mA

= 100mA

0.75

0.13 %

< 300mA 0.2

1

1.85

0.5

A

%

Regulation, PWM Mode
Output Voltage Load

Regulation, LDO Mode
Maximum Duty Cycle

PWM Switch ON­Resistance

100µA < I
V

LOWQ

V

≤ 0.4V

FB

LOAD

= 0V

< 50mA

ISW = 50mA VFB = 0.7V

= -50mA VFB = 1.1V

I

SW

(High Side Switch)

FB_NOM

FB_NOM

Oscillator Frequency

(Low Side Switch)

0.1

100

%

0.4

0.4

1.8

2

0.2

2.2

%

Ω

MHz

LOWQ threshold voltage

0.5

0.85

LOWQ Input Current 0.1
Enable Threshold

0.5

0.85

Enable Input Current 0.1

I

LDO Dropout Voltage

April 2005

= 50mA Note 5

OUT

110

3

1.3
2

1.3
2

V

µA

V

µA

mV

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Micrel, Inc. MIC2205

Parameter Condition Min Typ Max Units

60

75

120

Output Voltage Noise
LDO Current Limit LOWQ = 0V; V

Over-Temperature
Shutdown

Over-Temperature
Hysteresis

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: 1.5kΩ in series with 100pF.

4. Specification for packaged product only.

5. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value that is
initially measured at a 1V differential. For outputs below 2.7V, the dropout voltage is the input-to-output voltage differential with a
minimum input voltage of 2.7V.

LOWQ = 0V; C

160

20

= 2.2μF, 10Hz to 100kHz

OUT

= 0V (LDO Mode)

OUT

µVrms

mA

°C

°C

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Typical Characteristics – PWM Mode

80
70
60
50
40
30
20

GAIN (dB)

10

0

-10

-20

1E+2 1E+3 1E+4 1E+5 1E+6

100

95
90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

Bode Plot

Phase

VIN=3.6V

=1.8V

V

OUT

L=2.2 H
C

=2.2 F

OUT

= 120pF

C

FF

1k
FREQUENCY (Hz)

1.5V

VIN=4.2V

0 100 200 300 400

OUTPUT CURRENT (mA)

10k

Efficiency

OUT

VIN=3.6V

Gain

100k

VIN=3V

1M

144
126
108
90
72
54
36
18
0

-18

-36

PHASE (°)

2.5V

Efficiency

100

95
90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

0 100 200 300 400

95
90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

0 100 200 300 400

OUT

VIN=3V

VIN=3.6V

VIN=4.2V

OUTPUT CURRENT (mA)

1.38V

VIN=4.2V

OUTPUT CURRENT (mA)

Efficiency

OUT

VIN=3.6V

VIN=3V

1.8V

Efficiency

100

95
90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

0 100 200 300 400 500 600

95
90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

0 100 200 300 400

OUT

VIN=3V

VIN=3.6V

VIN=4.2V

OUTPUT CURRENT (mA)

1.2V

Efficiency

OUT

VIN=3V

VIN=3.6V

VIN=4.2V

OUTPUT CURRENT (mA)

1.0V

Efficiency

90
85
80
75
70
65

EFFICIENCY (%)

60
55
50

0 100 200 300 400 500 600

2.2

2.15

2.1

2.05
2

1.95

1.9

FREQUENCY (MHz)

1.85

1.8

-40 -20 0 20 40 60 80 100 120

OUT

VIN=3V

VIN=3.6V

VIN=4.2V

OUTPUT CURRENT (mA)

Frequency

vs. Temperature

VIN=3.6V

TEMPERATURE (°C)

1.010

1.008

1.006

1.004

1.002

1.000

0.998

0.996

0.994

FEEDBACK VOLTAGE (V)

0.992

0.990

1200

1000

CURRENT LIMIT (mA)

Load Regulation

VIN=3.6V
LowQ = V

IN

0 100 200 300 400

OUTPUT CURRENT (mA)

Peak Current Limit
vs. Supply Voltage

800

600

400

200

LowQ = V

0

2.7 3.4 4.1 4.8 5.5

IN

SUPPLY VOLTAGE (V)

Quiescent Current
vs. Supply Voltage

900
800
700
600
500
400
300
200

VIN=3.6V

100

V

QUIESCENT CURRENT (µA)

ENABLE THRESHOLD (V)

=0.9V

FB

0

2.7 3.4 4.1 4.8 5.5
SUPPLY VOLTAGE (V)

Enable Threshold

vs. Supply Voltage

1.5

1.4

1.3

1.2

1.1

1.0

0.9

0.8

0.7

0.6

LowQ = V

0.5

2.7 3.4 4.1 4.8 5.5

IN

SUPPLY VOLTAGE (V)

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Typical Characteristics – PWM Mode (cont.)

Turn-On Time

vs. Supply Voltage

100

90
80
70
60
50
40
30
20

TURN-ON DELAY (µs)

10

VIN=3.6V

0

2.7 3.4 4.1 4.8 5.5
SUPPLY VOLTAGE (V)

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Typical Characteristics - LDO Mode

PSRR

vs. Input Voltage

80

60

40

PSRR (dB)

I

20

OUT

V

OUT

C

OUT

0

1E-2 1E-1 1E+0 1E+1 1E+2 1E+3

0.01

0.1

vs. Supply Voltage

140
120
100

80
60
40

CURRENT LIMIT (mA)

20

0

2.7 3.4 4.1 4.8 5.5

SUPPLY VOLTAGE (V)

4.2V

=50mA

=1.8V

3.6V

=2.2 F

1

FREQUENCY (Hz)

10

Current Limit

LowQ = 0V

3V

100

PSRR

vs. Output Current

80

60

1k

40

PSRR (dB)

20

0

1E-2 1E-1 1E+0 1E+1 1E+2 1E+3

0.01

160
140
120
100

80
60
40
20

DROPOUT VOLTAGE (mV)

0

-40 -20 0 20 40 60 80 100120

I

OUT

VIN=3.6
V

=1.8V

OUT

=2.2 F

C

OUT

0.1
FREQUENCY (Hz)

Dropout Voltage
vs. Temperature

TEMPERATURE (°C)

=100 A

I

1

I

OUT

=50mA

OUT

10

V

OUT

I

= 50mA

OUT

LowQ = 0V

=0A

100

= 3.3V

1k

250

200

150

100

50

DROPOUT VOLTAGE (mV)

0

0 20406080100

80
70
60
50
40
30
20
10

DROPOUT VOLTAGE (mV)

0

-40 -20 0 20 40 60 80 100120

Dropout

vs. Output Current

V

=3.3V

OUT

OUTPUT CURRENT (mA)

Dropout Voltage
vs. Temperature

V

= 3.3V

OUT

I

= 25mA

OUT

LowQ = 0V

TEMPERATURE (°C)

Dropout Voltage
vs. Temperature

40
35
30
25
20
15
10

5

DROPOUT VOLTAGE (mV)

0

-40 -20 0 20 40 60 80 100120
TEMPERATURE (°C)

Enable Threshold Voltage

vs. Supply Voltage

1.5

1.4

1.3

1.2

1.1

1.0

0.9

0.8

0.7

ENABLE THRESHOLD (V)

0.6

0.5

2.7 3.4 4.1 4.8 5.5

SUPPLY VOLTAGE (V)

V

= 3.3V

OUT

I

= 10mA

OUT

LowQ = 0V

LowQ = 0V

Dropout Voltage
vs. Temperature

9
8
7
6
5
4
3
2
1

DROPOUT VOLTAGE (mV)

0

-40 -20 0 20 40 60 80 100120
TEMPERATURE (°C)

Turn-On Time

vs. Supply Voltage

100

90
80
70
60
50
40
30
20

TURN-ON DELAY (µs)

10

0

2.7 3.4 4.1 4.8 5.5

SUPPLY VOLTAGE (V)

V

OUT

I

= 1mA

OUT

LowQ = 0V

VIN=3.6V
LowQ = 0V

= 3.3V

1.836

1.827

1.818

1.809

1.800

1.791

1.782

OUTPUT VOLTAGE (V )

1.773

1.764

QUIESCENT CURRENT (µA)

Output Voltage

vs. Temperature

LowQ = 0V

-40 -20 0 20 40 60 80 100120
TEMPERATURE (°C)

Quiescent Current

vs. Temperature

25

I

=50mA

OUT

20

15

I

=100 A

OUT

10

5

0

-40 -20 0 20 40 60 80 100120
TEMPERATURE (°C)

I

=1mA

OUT

VIN=3.6V
LowQ = 0V

April 2005

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Typical Characteristics – LDO Mode (cont.)

Quiescent Current

vs. Temperature

25

I

=100 A

OUT

20

15

10

5

QUIESCENT CURRENT (µA)

0

012345

SUPPLY VOLTAGE (V)

Output Voltage

vs. Output Current

1.836

1.827

1.818

1.809

1.8

1.791

1.782

OUTPUT VOLTAGE (V)

1.773

1.764
0 20406080100

OUTPUT CURRENT (mA)

I

=60mA

OUT

I

LowQ = 0V

VIN=3.6V
V

OUT

LowQ = 0V

OUT

=0A

=1.8V

Quiescent Current

vs. Supply Voltage

25
24
23
22
21
20
19
18
17
16

QUIESCENT CURRENT (µA)

15

2.7 3.4 4.1 4.8 5.5
SUPPLY VOLTAGE (V)

I

=100 A

OUT

LowQ = 0V

Quiescent Current
vs. Output Current

25
24
23
22
21
20
19
18
17
16

QUIESCENT CURRENT (µA)

15

0 20406080100

OUTPUT CURRENT (mA)

VIN=3.6V
LowQ = 0V

April 2005

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Functional Diagram

VIN

AVIN

BIAS

EN

LOWQ

6

Enable and

Control Logic

Bias,

UVLO,

Thermal

Shutdown

LDO Block

LDO

Current

Limit

PWM

Control

Current Limit

HSD

Anti-Shoot

Through

LSD

N-Channel

Current Limit

Soft
Start

P-Channel

EA

1.0V

EA

1.0V

SW

FB

LDO

R1

R2

V

OUT

C

OUT

SGND

PGND

MIC2205 Block Diagram

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Functional Characteristics

Load Transient PWM Mode

LowQ = V

IN

(100mA/div)

Output Current

(50mV/div)

AC Coupled

Output Voltage

ENABLE

OUT

V

Time 20 s/div

Enable Transient PWM Mode

LowQ = 0V

(1V/div)

(50mV/div)

Time 40

s/div

April 2005

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Functional Characteristics

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⎛

⎞ ⎠ ⎟

Functional Description

VIN

VIN provides power to the MOSFETs for the switch
mode regulator section, along with the current
limiting sensing. Due to the high switching speeds, a
1µF capacitor is recommended close to VIN and the
power ground (PGND) pin for bypassing. Please
refer to layout recommendations.

AVIN

Analog V
section and the bias through an internal 6 Ohm
resistor. AVIN and VIN must be tied together.
Careful layout should be considered to ensure high
frequency switching noise caused by VIN is reduced
before reaching AVIN.

LDO

The LDO pin is the output of the linear regulator and
should be connected to the output. In LOWQ mode
(LOWQ<1.5V), the LDO provides the output voltage.
In PWM mode (LOWQ>1.5V) the LDO pin is high
impedance.

EN

The enable pin provides a logic level control of the
output. In the off state, supply current of the device
is greatly reduced (typically <1µA). Also, in the off
state, the output drive is placed in a "tri-stated"
condition, where both the high side P-channel
Mosfet and the low-side N-channel are in an “off” or
non-conducting state. Do not drive the enable pin
above the supply voltage.

LOWQ

The LOWQ pin provides a logic level control
between the internal PWM mode and the low noise
linear regulator mode. With LOWQ pulled low
(<0.5V), quiescent current of the device is greatly
reduced by switching to a low noise linear regulator
mode that has a typical I
mode the output can deliver 60mA of current to the
output. By placing LOWQ high (>1.5V), this
transitions the device into a constant frequency
PWM buck regulator mode. This allows the device
the ability to efficiently deliver up to 600mA of output
current at the same output voltage.

BIAS

The BIAS pin supplies the power to the internal
power to the control and reference circuitry. The bias
is powered from AVIN through an internal 6Ω
resistor. A small 0.1µF capacitor is recommended

April 2005

(AVIN) provides power to the LDO

IN

of 18µA. In linear (LDO)

Q

for bypassing.

FB

The feedback pin (FB) provides the control path to
control the output. For adjustable versions, a resistor
divider connecting the feedback to the output is used
to adjust the desired output voltage. The output
voltage is calculated as follows:

R1

V

= V

OUT

where V

×

⎜

REF

⎝

is equal to 1.0V.

REF

R2

+1

A feedforward capacitor is recommended for most
designs using the adjustable output voltage option.
To reduce battery current draw, a 100K feedback
resistor is recommended from the output to the FB
pin (R1). Also, a feedforward capacitor should be
connected between the output and feedback (across
R1). The large resistor value and the parasitic
capacitance of the FB pin can cause a high
frequency pole that can reduce the overall system
phase margin. By placing a feedforward capacitor,
these effects can be significantly reduced.
Feedforward capacitance (C

) can be calculated as

FF

follows:

C

=

FF

1

160kHzR12

××

π

For fixed options A feed forward capacitor from the
output to the FB pin is required. Typically a 100pF
small ceramic capacitor is recommended

SW

The switch (SW) pin connects directly to the inductor
and provides the switching current nessasary to
operate in PWM mode. Due to the high speed
switching on this pin, the switch node should be
routed away from sensitive nodes.

PGND

Power ground (PGND) is the ground path for the
high current PWM mode. The current loop for the
power ground should be as small as possible and
separate from the Analog ground (AGND) loop.
Refer to the layout considerations for more details.

SGND

Signal ground (SGND) is the ground path for the
biasing and control circuitry. The current loop for the
signal ground should be separate from the Power
ground (PGND) loop. Refer to the layout
considerations for more details.

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Applications Information

The MIC2205 is a 600mA PWM power supply that
utilizes a LOWQ™ light load mode to maximize
battery efficiency in light load conditions. This is
achieved with a LOWQ control pin that when pulled
low, shuts down all the biasing and drive current for
the PWM regulator, drawing only 18µA of operating
current. This allows the output to be regulated
through the LDO output, capable of providing 60mA
of output current. This method has the advantage of
producing a clean, low current, ultra low noise output
in LOWQ™ mode. During LOWQ™ mode, the SW
node becomes high impedance, blocking current
flow. Other methods of reducing quiescent current,
such as pulse frequency modulation (PFM) or
bursting techniques, create large amplitude, low
frequency ripple voltages that can be detrimental to
system operation.

When more than 60mA is required, the LOWQ pin
can be forced high, causing the MIC2205 to enter
PWM mode. In this case, the LDO output makes a
"hand-off" to the PWM regulator with virtually no
variation in output voltage. The LDO output then
turns off allowing up to 600mA of current to be
efficiently supplied through the PWM output to the
load.

Input Capacitor

A minimum 1µF ceramic is recommended on the
VIN pin for bypassing. X5R or X7R dielectrics are
recommended for the input capacitor. Y5V
dielectrics lose most of their capacitance over
temperature and are therefore, not recommended.

A minimum 1µF is recommended close to the VIN
and PGND pins for high frequency filtering. Smaller
case size capacitors are recommended due to their
lower ESR and ESL. Please refer to layout
recommendations for proper layout of the input
capacitor.

Output Capacitor

Even though the MIC2205 is optimized for a 2.2µF
output capacitor, output capacitance can be varied
from 1µF to 4.7µF. The MIC2205 utilizes type III
internal compensation and utilizes an internal high
frequency zero to compensate for the double pole
roll off of the LC filter. For this reason, larger output
capacitors can create instabilities. X5R or X7R
dielectrics are recommended for the output
capacitor. Y5V dielectrics lose most of their
capacitance over temperature and are therefore, not
recommended.

In addition to a 2.2µF, a small 10nF is recommended
close to the load for high frequency filtering. Smaller
case size capacitors are recommended due to there
lower ESR and ESL.

Inductor Selection

The MIC2205 is designed for use with a 2.2µH
inductor. Proper selection should ensure the
inductor can handle the maximum average and peak
currents required by the load. Maximum current
ratings of the inductor are generally given in two
methods; permissible DC current and saturation
current. Permissible DC current can be rated either
for a 40°C temperature rise or a 10% to 20% loss in
inductance. Ensure that the inductor selected can
handle the maximum operating current. When
saturation current is specified, make sure that there
is enough margin that the peak current will not
saturate the inductor. Peak inductor current can be
calculated as follows:

⎛
⎜

1V

OUT

⎜
⎝

+=

II

OUTPK

⎞

V

OUT

⎟

−

⎟

V

IN

⎠

Lf2

××

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Micrel, Inc. MIC2205

Layout Recommendations

V

OUT

GND

V

IN

BIAS

C

L1

Note:

C

R1

BIAS

C

C

R1

MIC2205

FF

R2

Top

L
1

MIC2205

FF

R2

Bottom

LowQ
EN

V

OUT

GND

V

IN

LowQ
EN

The above figures demonstrate the recommended layout for the MIC2205 adjustable option.

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Micrel, Inc. MIC2205

2.7V to 5.5V

2.7V to 5.5V

V

GND

V

GND

MIC2205

C2

8

VIN

4

AVINSWLDO

6

EN

7

LOWQ

3

BIAS

PGND

AGND

10 1

FB

IN

C1

1µF

LowQ

0.1µF

Adjustable Output

MIC2205

C2

8

VIN

4

AVINSWLDO

6

EN

7

LOWQ

3

BIAS

PGND

AGND

10 1

FB

IN

C1

1µF

LowQ

0.1µF

Fixed Output

2.2µH

9

2

2.2µH

C3
100pF

C3
100pF

R1
100k

5

R2
125k

9

2

5

V

C4

2.2µF

GND

V

C4

2.2µF

GND

OUT

OUT

Item Part Number Description Manufacturer Qty

C1

06036D105MAT2
GRM185R60J105KE21D

C4

06036D225MAT2

GRM188R61A225KE34
C3 VJ0402A101KXAA 100pF Ceramic Capacitor Vishay
C2

0201ZD103MAT2

GRM033R10J103KA01D
L1

LQH32CN2R2M53K

CDRH2D14-2R2

(1)

R1

CRCW04021002F 100kΩ 1% 0402 Vishay Dale

(1)

R2

CRCW04026652F

CRCW04021243F

CRCW04022003F

CRCW04024023F

U1

Notes:

1. For adjustable version only.

2. Sumida Tel: [phone]

3. Murata Tel: [phone]

4. Vishay Tel: [phone]

5. Micrel, Inc. Tel: [phone]

MIC2205BML

1µF Ceramic Capacitor X5R, 6.3V 0603
1µF Ceramic Capacitor X5R, 6.3V 0603

2.2µF Ceramic Capacitor X5R, 10V 0603

2.2µuF Ceramic Capacitor X5R, 10V 0603

10nF Ceramic Capacitor 6.3V 0201
10nF Ceramic Capacitor 6.3V 0201

2.2µH Inductor 97mΩ 3.2mmx2.5mmx1.55mm

2.2µH Inductor 94mΩ 3.2mmx3.2mmx1.55mm

66.5 kΩ 1% 0402 For 2.5V
124 kΩ 1% 0402 For 1.8 V
200 kΩ 1% 0402 For 1.5 V
402 kΩ 1% 0402 For 1.2 V
Open For 1.0 V

OUT

OUT
OUT
OUT

OUT

2MHz Synchronous Buck Regulator with LOWQTM
Mode

AVX

(4)

Murata
AVX

Murata

AVX
Murata

Murata
Sumida

(4)

(3)

1

(4)

(4)

(2)

Vishay Dale
Vishay Dale
Vishay Dale
Vishay Dale
Vishay Dale

Micrel, Inc.

1

1

1

1

(3)

1

(3)
(3)
(3)
(3)
(3)

(5)

1

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M9999-041105

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Micrel, Inc. MIC2205

Package Information

10-Lead MLF™ (ML)

MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA

TEL [phone] FAX [phone] 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

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 its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer.

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.

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