MICRF300
100MHz to 1000MHz, 1.8 to 3.6V,
Low-Noise Amplifier with Shutdown
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
General Description
The MICRF300 is a low-noise amplifier (LNA) with low-
power shutdown mode, which operates over the
100MHz to 1000MHz frequency band. The device is
targeted for low-power, low-data rate applications at
315/433MHz, achieving a low 1.2dB noise figure with
18dB of gain, helping to improve receiver noise figure
and sensitivity. The device also performs well at
868/915MHz, achieving 13dB of gain and a noise figure
of 1.7dB. The device requires a simple input matching
network and output matching network to optimize
performance for the desired frequency band.
The MICRF300 operates over the 1.8V to 3.6V voltage
range. Consuming a low 2.5mA of supply current during
operation and a typical 50nA of shutdown current, the
MICRF300 is an ideal solution for battery powered
equipment. The device is available in 6-pin SC70
package and is rated to operate over the -40˚C to
+125˚C temperature range.
Features
• 1.8V to 3.6V supply voltage range
• 2.5mA operating supply current
• 1μA (Max) shutdown current over temperature
• 18.3dB gain at 315MHz/433.92MHz
• 1.15dB noise figure at 315MHz/433.92MHz
• -25dBm input P1dB compression point at 433.92MHz
• -40˚C to +125˚C operating temperature range
• Small 6-pin SC70 package
Applications
• Security systems
• Remote keyless entry (RKE)
• Tire pressure monitoring (TPMS)
• Automated meter reading (AMR)
• Garage door openers (GDO)
• Remote weatherstations
Typical Application Circuit
Typical Performance an d Matching Component Values
fRF
(MHz) ICC
(mA) Gain
(dB) NF
(dB) IP1dB
(dBm) IIP3
(dBm) L1
(nH) C1
(pF) L2
(nH) C2
(pF)
315 2.5 18.5 1.15 -26.5 -15 33 1000 47 5.6
433.92 2.5 18.3 1.15 -25 -13 22 1000 33 3.9
900 2.5 13.6 1.7 -21 -10 2.7 270 10 1.8
April 2012 M9999-041712-B
RadioTech@micrel.com
or (408) 944-0800
Micrel, Inc. MICRF300
April 2012 2 M9999-041712-B
Ordering Information
Part Number Temp. Range Package Top Mark
MICRF300YC6 –40°C to +125°C SC70-6 XE1
Notes:
1. Under bar symbol (_) may not be to scale.
Pin Configur ation
SC70-6 (C6)
Pin Description
Pin
Number Pin
Name Pin Function
1 EN Enable Logic Input. Logic high enables the part. Logic low disables the part.
2, 4 GND Ground. Connect to PCB ground plane.
3 RFIN RF Input. DC blocking and matching network is required.
5 RFOUT RF Output. Connect a pull-up inductor to the supply and a matching network to the load.
6 VCC Supply Voltage. Connect a 0.1μF bypass capacitor as close to the pin as possible.
Micrel, Inc. MICRF300
April 2012 3 M9999-041712-B
Absolute Maximum Ratings(1)
Supply Voltage (VCC)..................................-0.3V to +3.9V
EN Voltage (VEN). ............................. −0.3V to VCC + 0.3V
Maximum Junction Temperature (TJ)....................+150ºC
Storage Temperature (TS)......................−65ºC to +150°C
Lead Temperature (soldering, 10sec.)..................+260°C
Maximum Input Power .................. +10dBm (50Ω source)
ESD Rating (3)
HBM...................................................................1.5kV
MM..................................................................... 100V
Operating Ratings(2)
Supply Voltage (VCC) ............................. +1.8V to +3.6V
EN Voltage (VEN) ............................................ 0V to VCC
Ambient Temperature (TA)..................–40°C to +125°C
RFIN DC voltage .........................................AC coupled
Frequency Range........................ 100MHz to 1000MHz
Thermal Resistance (θJA) ................................ 260˚C/W
ELECTRICAL CHARACTERISTICS TABLE(4)
VCC = +2.7V, TA = +25°C, bold values indicate –40°C≤ TA ≤ +125°C, unless noted.
Parameter Condition Min Typ Max Units
VEN = 0V, TA = +25ºC 0.05 0.5 Shutdown Current (ISHDN)
VEN = 0V
1 μA
Operating Supply Current (ICC) VEN = VCC 2.5 4 mA
EN Logic-Low (VIL)
0.2 V
EN Logic-High (VIH) 1.2 V
VEN = 0.2V 20 nA
EN Input Current VEN = 2.2V 28 40 μA
fRF = 315MHz 18.5
fRF = 433.92MHz 14 18.3
Gain
fRF = 900MHz 10 13.6
dB
fRF = 315MHz 1.15
fRF = 433.92MHz 1.15
Noise Figure (NF)
fRF = 900MHz 1.7
dB
fRF = 315MHz –15
fRF = 433.92MHz –13
Input 3rd Order Intercept Point (IIP3)
(Note 5)
fRF = 900MHz –10
dBm
fRF = 315MHz –27
fRF = 433.92MHz –25
Input 1dB compression (P1dB)
fRF = 900MHz –21
dBm
Enable Time fRF = 315MHz; 433.92MHz 10 μs
Disable Time fRF = 315MHz; 433.92MHz 10 μs
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. IIP3 is measured with two tones located at 433MHz and 433.92MHz or 899MHz and 900MHz with -40dBm/tone.
Micrel, Inc. MICRF300
April 2012 4 M9999-041712-B
Typical Characteristics
Supply Current
vs Enable Voltage
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Enable Input Current
vs Enable Voltage
0
5
10
15
20
25
30
35
40
45
50
55
60
Suppl y Current vs Supply
Voltage
1.5
2.0
2.5
3.0
3.5
4.0
+125ºC
+125ºC
1.8 2.4 3 3.6
SUPPLY CURRENT (mA)
SUPPLY VO LT A GE ( V)
+85ºC
+25ºC
-40ºC
0.0 0.5 1.0 1.5 2.0 2.5 3.0
SUPP LY CURRENT (mA)
ENABLE VOLTAGE (V)
+85ºC
0.0 0.6 1.2 1.8 2.4 3.0 3.6
ENABLE CURRENT (μA)
ENA BL E VOLTAG E (V)
+25ºC
+125ºC
-40ºC
VCC = 2.7V
+85ºC -40ºC
+25ºC
IIP3 vs Suppl y Voltage
f
RF
= 31 5MHz
-20
-19
-18
-17
-16
-15
-14
-13
-12
-11
-10
1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)
Input P1dB vs Supply Voltage
f
RF
= 3 15MHz
-29
-28
-27
-26
-25
-24
1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)
Gai n vs Suppl y Voltage
f
RF
= 315 MH z
15.0
15.5
16.0
16.5
17.0
17.5
18.0
18.5
19.0
19.5
20.0
INPUT IP3 (dBm)
+125ºC
+85ºC
+25ºC
-40ºC
INPUT P1dB (dBm)
+125ºC
+85ºC
+25ºC
-40ºC
1.8 2.1 2.4 2.7 3.0 3.3 3.6
GAIN (dB)
SUPPLY VO L TAG E (V)
+125ºC
+25ºC
-40ºC
IIP3 vs Suppl y Voltage
f
RF
= 43 3.92MH z
-17
-16
-15
-14
-13
-12
-11
-10
-9
INPUT IP3 (dBm)
-18
1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)
+125ºC
+85ºC
+25ºC
-40ºC
Input P1dB vs Supply Voltage
f
RF
= 4 33.92MHz
-27
-26
-25
-24
-23
-22
INPUT P1dB (dBm)
-28
1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)
+125ºC
+85ºC
+25ºC
-40ºC
Gai n vs Suppl y Voltage
f
RF
= 433.92MH z
15.0
15.5
16.0
16.5
17.0
17.5
18.0
18.5
19.0
19.5
20.0
GAIN (dB)
1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VO L TAG E (V)
+125ºC +25ºC
-40ºC
Micrel, Inc. MICRF300
April 2012 5 M9999-041712-B
Typical Characteristics (Continued)
Gai n vs Suppl y Volt age
f
RF
= 900 MH z
10.0
10.5
11.0
11.5
12.0
12.5
13.0
13.5
14.0
14.5
15.0
15.5
16.0
Input P1dB vs Supply Voltage
f
RF
= 9 00MHz
-23
-22
-21
-20
-19
-18
IIP3 vs Suppl y Voltage
f
RF
= 90 0MHz
-11.5
-11.0
-10.5
-10.0
-9.5
-9.0
-8.5
-8.0
-7.5
-7.0
+125ºC
+125ºC
-12.0
1.8 2.1 2.4 2.7 3.0 3.3 3.6
INPUT IP3 (dBm)
SUPPLY V OLTAGE (V )
+85ºC
+25ºC
-40ºC
-24
1.8 2.1 2.4 2.7 3.0 3.3 3.6
INPUT P1dB (dBm)
SUPPLY VOLTAGE (V)
+85ºC
+25ºC
-40ºC
1.8 2.1 2.4 2.7 3.0 3.3 3.6
GAIN (dB)
SUPPLY VO L TAG E (V)
+125ºC +25ºC
-40ºC
S- Parameters vs Frequency
f
RF
= 315 MH z (ma tched)
-60
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
0123456
S- PARAM ET ERS ( dB)
FREQ UE NCY ( GHz)
S21
S11
S12
S22
S-Parameters vs Frequency
f
RF
= 433MHz ( m atched)
-60
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
0123456
S- PARAMETERS ( d B)
FREQUENCY (G Hz)
S21
S11 S22
S21
S-Parameters vs Frequency
f
RF
= 900MHz ( m atched)
-60
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
20
S21
S11
0123456
S- PARAMETERS ( d B)
FREQUENCY (G Hz)
S22
S12
S- Parameters vs Frequency
f
RF
= 315 MH z (ma tched)
-25
-20
-15
-10
-5
0
5
10
15
20
S- PARAM ET ERS ( dB)
100 150 200 250 300 350 400 450 500
FREQUENCY ( MHz)
S21
S11
S22
S-Parameters vs Frequency
f
RF
= 4 33.92MHz ( m atched)
-25
-20
-15
-10
-5
0
5
10
15
20
S- PARAMETERS ( d B)
200 250 300 350 400 450 500 550 600
FRE QUENC Y (M H z)
S21
S11
S22
S-Parameters vs Frequency
f
RF
= 900MHz ( m atched)
-25
-20
-15
-10
-5
0
5
10
15
20
S- PARAMETERS ( d B)
700 750 800 850 900 950 1000 1050 1100
FREQUENCY ( M Hz)
S21
S11
S22
Micrel, Inc. MICRF300
April 2012 6 M9999-041712-B
Typical Characteristics (Continued)
Noise Figure Di stribution
f
RF
= 43 3.92MH z
0
2
4
6
8
10
12
14
to 1.1
1.15
to 1.2
1.25
to 1.3
# OF BOARDS
1.05
1.1 to
1.15
1.2 to
1.25
NOIS E F IGURE (dB)
Micrel, Inc. MICRF300
April 2012 7 M9999-041712-B
Functional Description Output Bias an d Matching
The MICRF300 is a low-noise amplifier (LNA) which
operates over the 100 to 1000MHz frequency range. The
device operates from a 1.8V to 3.6V voltage supply, where
it consumes 2.5mA of supply current during operation, and
1μA (max) of current in shutdown. A simple LC input
matching network is required to optimize the device for
best noise figure. A simple LC network is required to bias
the output stage and match the output to the following
stage. Recommended matching networks have been
provided for 315MHz, 433.92MHz and 900MHz. See
Evaluation Board and Bill of Materials for recommended
component values. See Figure 1 for Block Diagram of the
MICRF300.
The output stage has an internal pull-up resistor of 250Ω.
To resonate out any parasitic capacitance and to increase
output swing capability, a multi-layer ceramic inductor
should be connected from the RF output, RFOUT (Pin 5)
pin to VCC. See recommended component values in the
Typical Performance and Matching Component Values
table of the data sheet.
Enable
The MICRF300 features a logic-level enable, EN (Pin 1). A
logic-level low disables the device. A logic-level High
enables the device. The value of the input DC-blocking
capacitor will affect the enable and disable time of the
device.
Input Matching
The RF input pin, RFIN (Pin 3) is directly connected to the
base of the RF input device. In normal operation, the DC
voltage of this pin is one diode above GND. The
MICRF300 requires an input matching network for optimal
noise figure, gain and linearity. A series inductor and a DC-
blocking capacitor are required to implement this network.
A high-Q, wire-wound type inductor is recommended for
lowest noise figure at 315MHz and 433.92MHz. A
standard multi-layer ceramic inductor can be used, but the
noise figure degrades by 0.2 dB. At 900MHz, a standard
multi-layer ceramic inductor may be used as the
inductance value is very low, and the Q does not make a
measurable difference. See recommended component
values in the Typical Performace and Matching Component
Values section of the data sheet.
Power Supply Bypassing
Minimum supply bypassing is needed on PCB board to
filter out AC fluctuations in supply voltage. It is achieved by
placing a 0.1μF capacitor as close as possible between the
VCC (Pin 6) and GND (Pins 2 and 4). Refer to the
MICRF300 Evaluation Board for recommend layout.
Functional Diagram
Figure 1: Block Diagram
Micrel, Inc. MICRF300
April 2012 8 M9999-041712-B
Package Information
SC70-6 (C6)
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 US
A
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical impla
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
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can nt
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