AT-41532
General Purpose, Low Current NPN Silicon Bipolar Transistor
Data Sheet
3-Lead SC-70 (SOT-323)
Surface Mount Plastic Package
Pin Conguration
Features
• General Purpose NPN Bipolar Transistor Optimized for
Low Current, Low Voltage Applications at 900 MHz,
1.8 GHz, and 2.4 GHz
• Performance (5 V, 5 mA)
0.9 GHz: 1 dB NF, 15.5 dB GA
1.8 GHz: 1.4 dB NF, 10.5 dB GA
2.4 GHz: 1.9 dB NF, 9 dB GA
• Characterized for 3, 5, and 8 V Use
• Miniature 3-lead SOT-323 (SC-70) Plastic Package
• High Breakdown Voltage (can be operated up to 10 V)
• Lead-free
Applications
• LNA, Oscillator, Driver Amplier, Buer Amplier, and
Down Converter for Cellular and PCS Handsets and
Cordless Telephones
• LNA, Oscillator, Mixer, and Gain Amplier for Pagers
• Power Amplier and Oscillator for RF-ID Tag
• LNA and Gain Amplier for GPS
• LNA for CATV Set-Top Box
Description
Avago’s AT-41532 is a general purpose NPN bipolar transis-
tor that has been optimized for maximum ft at low voltage
operation, making it ideal for use in battery powered
applications in cellular/PCS and other wireless markets.
The AT-41532 uses the miniature 3-lead SOT-323 (SC-70)
plastic package.
Optimized performance at 5 V makes this device ideal
for use in 900 MHz, 1.8 GHz, and 2.4 GHz systems. Typical
amplier design at 900 MHz yields 1 dB NF and 15.5 dB as-
sociated gain at 5 V and 5 mA bias. High gain capability
at 1 V and 1 mA makes this device a good t for 900 MHz
pager applications. A good noise match near 50 ohms at
900 MHz makes this a very user-friendly device. Moreover,
voltage breakdowns are high enough to support operation
at 10 V.
The AT-41532 belongs to Avago’s AT-4XXXX series bipolar
transistors. It exhibits excellent device uniformity, per-
formance, and reliability as a result of ion-implantation,
self-alignment techniques, and gold metalization in the
fabrication process.
BASE EMITTER
COLLECTOR
41
2
Electrical Specications, TA = 25°C
Symbol Parameters and Test Conditions Units Min Typ Max
hFE Forward Current Transfer Ratio
VCE = 5 V,
IC = 5 mA
– 30 150 270
ICBO Collector Cuto Current VCB = 3 V mA 0.2
IEBO Emitter Cuto Current VEB = 1 V mA 1.0
Characterization Information, TA = 25°C
Symbol Parameters and Test Conditions Units Min Typ
NF Noise Figure
VCE = 5 V, IC = 5 mA
f = 0.9 GHz
f = 1.8 GHz
f = 2.4 GHz
dB 1.0
1.4
1.9
GAAssociated Gain
VCE = 5 V, IC = 5 mA
f = 0.9 GHz
f = 1.8 GHz
f = 2.4 GHz
dB 15.5
10.5
9.0
P1dB Power at 1 dB Gain Compression (opt tuning)
VCE = 5 V, IC = 25 mA
f = 0.9 GHz dBm 14.5
G1dB Gain at 1 dB Gain Compression (opt tuning)
VCE = 5 V, IC = 25 mA
f = 0.9 GHz dB 14.5
IP3 Output Third Order Intercept Point (opt tuning)
VCE = 5 V, IC = 25 mA
f = 0.9 GHz dBm 25
|S21E|2 Gain in 50 Ω System
VCE = 5 V, IC = 5 mA
f = 0.9 GHz
f = 2.4 GHz
dB 12.5 13.25
5.2
AT-41532 Absolute Maximum Ratings
Symbol Parameter Units
Absolute
Maximum[1]
VEBO Emitter-Base Voltage V 1.5
VCBO Collector-Base Voltage V 20
VCEO Collector-Emitter Voltage V 12
IC Collector Current mA 50
PT Power Dissipation[2, 3] mW 225
Tj Junction Temperature °C 150
TSTG Storage Temperature °C -65 to 150
Thermal Resistance [2]:
qjc = 350°C/W
Notes:
1. Operation of this device above any one of
these parameters may cause permanent
damage.
2. TMOUNTING SURFACE = 25°C.
3. Derate at 2.86 mW/°C for TMOUNTING SURFACE
> 72°C.
3
AT-41532 Typical Performance
0
4.0
3.5
2.5
2.0
3.0
0.5
1.5
1.0
0 2.01.0 3.0 4.0
NOISE FIGURE (dB)
FREQUENCY (GHz)
Figure 1. AT-41532 Typical Noise Figure vs.
Frequency at 1 V, 1 mA.
2 mA
5 mA
0
3.5
1.5
2.0
0.5
1.0
0 2.01.0 3.0 4.0
NOISE FIGURE (dB)
FREQUENCY (GHz)
Figure 2. AT-41532 Typical Noise Figure vs.
Frequency and Current at 2.7 V.
2.5
3.0 2 mA
5 mA
3.5
1.5
2.0
0.5
1.0
2.5
3.0
0
0 2.01.0 3.0 4.0
NOISE FIGURE (dB)
FREQUENCY (GHz)
Figure 3. AT-41532 Typical Noise Figure vs.
Frequency and Current at 5 V.
0
10
4
6
2
0.5 2.0 2.51.0 1.5 3.0 3.5 4.0
GAIN (dB)
FREQUENCY (GHz)
Figure 4. AT-41532 Associated Gain vs.
Frequency at 1 V, 1 mA.
8
0
16
8
12
4
0.5 4.0
GAIN (dB)
FREQUENCY (GHz)
Figure 5. AT-41532 Associated Gain vs.
Frequency and Current at 2.7 V.
FREQUENCY (GHz)
Figure 6. AT-41532 Associated Gain vs.
Frequency and Current at 5 V.
-10
20
15
10
-5
5
0
0 15105 20 25
P1 dB (dBm)
COLLECTOR CURRENT (mA)
Figure 7. AT-41532 P1 dB vs. Collector Current
and Voltage (valid up to 2.4 GHz).
2.0 2.51.0 1.5 3.0 3.5
2 mA
5 mA
2 mA
5 mA
0
16
8
12
4
0.5 4.0
GAIN (dB)
2.0 2.51.0 1.5 3.0 3.5
2.7 V
5 V
0
9
8
7
2
1
3
6
4
5
0 15105 20 25
G1 dB (dB)
COLLECTOR CURRENT (mA)
Figure 8. AT-41532 G1 dB vs. Collector Current
and Voltage (valid up to 2.4 GHz).
2.7 V
5 V
4
AT-41532 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 1 V, IC = 1 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.787 -75 8.79 2.750 125 -20.18 0.098 49 0.860 -22
0.75 0.697 -104 7.28 2.311 106 -18.74 0.116 38 0.785 -28
1.0 0.620 -128 5.84 1.960 90 -18.40 0.120 31 0.734 -32
1.5 0.554 -166 3.40 1.480 66 -18.80 0.115 30 0.678 -40
2.0 0.538 -164 1.52 1.191 48 -18.69 0.116 42 0.653 -50
3.0 0.543 118 -1.06 0.886 22 -13.30 0.216 60 0.620 -73
4.0 0.559 79 -2.61 0.741 5 -8.03 0.397 47 0.568 -102
5.0 0.561 47 -3.06 0.703 -7 -4.83 0.574 24 0.487 -137
6.0 0.545 28 -2.81 0.724 -20 -3.11 0.699 0 0.398 -180
7.0 0.534 14 -2.46 0.754 -35 -2.30 0.768 -23 0.362 130
8.0 0.544 2 -2.38 0.761 -52 -2.08 0.787 -44 0.407 88
9.0 0.563 -10 -2.49 0.751 -68 -2.18 0.778 -63 0.467 58
10.0 0.597 -23 -2.79 0.725 -84 -2.52 0.748 -80 0.523 35
11.0 0.655 -34 -3.39 0.677 -100 -3.15 0.696 -96 0.593 16
12.0 0.703 -42 -4.03 0.629 -112 -3.76 0.649 -110 0.665 -6
AT-41532 Typical Noise Parameters,
Common Emitter, ZO = 50 Ω, VCE = 1 V, IC = 1 mA
Freq.
GHz
Fmin
dB
Γopt Rn
ohms
Gassoc
dBMag Ang
0.9 1.4 0.44 92 12.4 9.4
1.8 1.8 0.57 -183 3.0 7.6
2.0 1.9 0.60 -169 3.3 6.7
2.5 2.2 0.66 -140 10.1 5.7
3.0 2.6 0.71 -116 27.6 4.6
3.5 3.1 0.75 -95 59.9 3.5
4.0 3.6 0.77 -77 103.0 2.1
gmax
dB(S|2,1|)
k
-4
20
8
12
0
4
0 21 3 4 5 6
GAIN (dB)
0
1.50
0.75
1.25
1.00
0.25
0.50
k
FREQUENCY (GHz)
16
Figure 9. Gain vs. Frequency at 1 V, 1 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
5
AT-32032 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 2.7 V, IC = 2 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.647 -82 13.45 4.702 119 -23.97 0.063 52 0.808 -21
0.75 0.532 -111 11.34 3.691 101 -22.60 0.074 46 0.737 -24
1.0 0.455 -134 9.54 3.000 88 -21.87 0.081 46 0.696 -27
1.5 0.394 -171 6.70 2.162 68 -20.48 0.095 52 0.658 -33
2.0 0.382 160 4.64 1.707 51 -18.50 0.119 59 0.643 -40
3.0 0.397 116 1.87 1.240 26 -13.56 0.210 61 0.627 -59
4.0 0.434 80 0.03 1.004 5 -9.26 0.344 50 0.604 -81
5.0 0.474 50 -1.20 0.871 -10 -6.05 0.498 32 0.556 -108
6.0 0.497 30 -1.81 0.812 -23 -3.84 0.643 11 0.470 -142
7.0 0.501 15 -1.88 0.805 -36 -2.40 0.759 -12 0.377 174
8.0 0.512 4 -1.89 0.804 -51 -1.73 0.819 -34 0.361 123
9.0 0.532 -9 -1.99 0.796 -67 -1.61 0.831 -55 0.411 82
10.0 0.569 -22 -2.31 0.767 -83 -1.86 0.808 -74 0.476 52
11.0 0.643 -32 -2.37 0.762 -97 -2.41 0.758 -93 0.562 27
12.0 0.687 -40 -3.51 0.668 -112 -3.10 0.700 -107 0.639 1
AT-32032 Typical Noise Parameters,
Common Emitter, ZO = 50 Ω, VCE = 2.7 V, IC = 2 mA
Freq.
GHz
Fmin
dB
Γopt Rn
ohms
Gassoc
dBMag Ang
0.9 1.2 0.35 100 8.7 12.9
1.8 1.6 0.48 -179 3.3 9.7
2.0 1.7 0.51 -165 3.7 9.1
2.5 1.9 0.60 -136 8.9 8.0
3.0 2.2 0.65 -112 21.0 6.9
3.5 2.5 0.70 -91 42.0 5.9
4.0 2.9 0.74 -74 72.0 5.1
gmax
dB(S|2,1|)
k
-4
20
8
12
0
4
0 21 3 4 5 6
GAIN (dB)
0
1.2
0.6
1
0.8
0.2
0.4
k
FREQUENCY (GHz)
16
Figure 10. Gain vs. Frequency at 2.7 V, 2 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
6
AT-41532 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 2.7 V, IC = 5 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.400 -102 17.03 7.106 106 -25.97 0.050 59 0.671 -22
0.75 0.312 -130 14.15 5.101 91 -23.86 0.064 60 0.615 -24
1.0 0.270 -152 11.97 3.969 80 -22.09 0.079 61 0.588 -25
1.5 0.247 175 8.82 2.762 64 -19.10 0.111 63 0.564 -30
2.0 0.253 149 6.67 2.154 50 -16.60 0.148 62 0.553 -37
3.0 0.280 112 3.86 1.559 26 -12.48 0.238 55 0.535 -54
4.0 0.323 80 2.07 1.269 6 -9.19 0.347 43 0.514 -75
5.0 0.379 55 0.80 1.097 -12 -6.55 0.471 27 0.472 -99
6.0 0.434 38 -0.13 0.986 -28 -4.50 0.595 9 0.398 -130
7.0 0.480 24 -0.72 0.920 -43 -2.96 0.711 -11 0.309 -174
8.0 0.522 10 -1.20 0.871 -58 -2.07 0.788 -32 0.299 131
9.0 0.557 -5 -1.64 0.828 -72 -1.73 0.820 -53 0.366 87
10.0 0.595 -19 -2.17 0.779 -87 -1.86 0.808 -73 0.449 55
11.0 0.662 -29 -2.38 0.761 -99 -2.43 0.756 -92 0.533 27
12.0 0.709 -39 -3.56 0.664 -115 -3.03 0.705 -107 0.633 3
AT-41532 Typical Noise Parameters,
Common Emitter, ZO = 50 Ω, VCE = 2.7 V, IC = 5 mA
Freq.
GHz
Fmin
dB
Γopt Rn
ohms
Gassoc
dBMag Ang
0.9 1.2 0.283 106 7.3 14.0
1.8 1.4 0.41 -165 3.9 10.7
2.0 1.5 0.44 -151 4.8 9.8
2.5 1.7 0.53 -126 9.2 8.5
3.0 1.9 0.60 -106 18.4 7.5
3.5 2.2 0.67 -86 35.0 6.6
4.0 2.5 0.71 -69 58.0 5.8
gmax
dB(S|2,1|)
k
-5
25
15
20
5
0
10
0 21 3 4 5 6
GAIN (dB)
0
1.2
0.8
1
0.2
0.4
0.6
k
FREQUENCY (GHz)
Figure 11. Gain vs. Frequency at 2.7 V, 5 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
7
AT-41532 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 2.7 V, IC = 10 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.243 -122 18.39 8.310 97 -26.90 0.045 68 0.586 -21
0.75 0.199 -149 15.19 5.751 85 -23.99 0.063 69 0.552 -21
1.0 0.184 -169 12.88 4.408 76 -21.74 0.082 69 0.536 -23
1.5 0.186 161 9.64 3.034 62 -18.35 0.121 67 0.520 -28
2.0 0.199 139 7.44 2.354 49 -15.79 0.162 63 0.510 -35
3.0 0.232 107 4.61 1.700 27 -11.93 0.253 52 0.491 -52
4.0 0.275 79 2.84 1.387 6 -9.00 0.355 39 0.467 -72
5.0 0.334 56 1.60 1.202 -12 -6.66 0.465 24 0.424 -95
6.0 0.399 41 0.66 1.079 -29 -4.79 0.576 7 0.349 -125
7.0 0.462 27 -0.02 0.997 -45 -3.30 0.684 -12 0.261 -167
8.0 0.521 14 -0.67 0.926 -60 -2.34 0.764 -32 0.251 134
9.0 0.566 -2 -1.26 0.865 -75 -1.89 0.805 -52 0.328 88
10.0 0.609 -18 -1.88 0.805 -90 -1.92 0.802 -72 0.422 56
11.0 0.678 -28 -2.97 0.711 -101 -2.32 0.766 -91 0.485 29
12.0 0.722 -39 -3.38 0.678 -116 -3.02 0.706 -106 0.620 3
gmax
dB(S|2,1|)
k
0
25
15
20
5
10
0 21 3 4 5 6
GAIN (dB)
0
1.25
0.75
1
0.25
0.5
k
FREQUENCY (GHz)
Figure 12. Gain vs. Frequency at 2.7 V, 10 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
8
AT-41532 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 5 V, IC = 2 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.659 -79 13.43 4.696 121 -25.16 0.055 53 0.836 -18
0.75 0.540 -108 11.41 3.720 103 -23.78 0.065 48 0.774 -22
1.0 0.456 -131 9.64 3.034 89 -23.06 0.070 48 0.738 -24
1.5 0.387 -169 6.81 2.190 69 -21.69 0.082 55 0.705 -30
2.0 0.371 162 4.74 1.726 53 -19.63 0.104 63 0.694 -37
3.0 0.387 116 1.91 1.247 27 -14.40 0.191 67 0.685 -54
4.0 0.428 79 0.01 1.001 7 -9.89 0.320 56 0.673 -75
5.0 0.472 49 -1.31 0.860 -8 -6.47 0.475 38 0.635 -100
6.0 0.494 28 -1.96 0.798 -20 -4.05 0.627 17 0.556 -131
7.0 0.490 13 -1.95 0.799 -33 -2.36 0.762 -5 0.448 -170
8.0 0.489 2 -1.81 0.812 -48 -1.51 0.840 -29 0.388 141
9.0 0.506 -10 -1.84 0.810 -64 -1.28 0.863 -51 0.408 96
10.0 0.541 -22 -2.07 0.788 -80 -1.51 0.841 -71 0.462 62
11.0 0.634 -33 -2.46 0.754 -94 -2.09 0.786 -90 0.539 35
12.0 0.670 -39 -3.23 0.689 -109 -2.75 0.729 -105 0.625 6
AT-41532 Typical Noise Parameters,
Common Emitter, ZO = 50 Ω, VCE = 5 V, IC = 2 mA
Freq.
GHz
Fmin
dB
Γopt Rn
ohms
Gassoc
dBMag Ang
0.9 1.2 0.35 100 8.5 13.5
1.8 1.5 0.48 178 3.4 10.6
2.0 1.6 0.51 -166 3.7 9.7
2.5 1.9 0.60 -137 8.8 8.8
3.0 2.2 0.65 -112 21.7 7.8
3.5 2.5 0.70 -92 44.6 7.1
4.0 2.9 0.74 -73 79.5 6.0
gmax
dB(S|2,1|)
k
-5
25
15
20
5
0
10
0 21 3 4 5 6
GAIN (dB)
0
1.2
0.8
1
0.2
0.4
0.6
k
FREQUENCY (GHz)
Figure 13. Gain vs. Frequency at 5 V, 2 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
9
AT-41532 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 5 V, IC = 5 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.402 -98 17.27 7.303 107 -27.15 0.044 60 0.713 -19
0.75 0.304 -124 14.42 5.260 92 -25.04 0.056 61 0.663 -21
1.0 0.255 -147 12.25 4.095 82 -23.26 0.069 63 0.640 -23
1.5 0.225 178 9.09 2.848 65 -20.23 0.097 66 0.621 -28
2.0 0.227 151 6.92 2.218 52 -17.66 0.131 65 0.613 -34
3.0 0.256 111 4.06 1.596 28 -13.38 0.214 59 0.603 -51
4.0 0.301 79 2.22 1.291 8 -9.92 0.319 48 0.592 -69
5.0 0.359 53 0.92 1.111 -10 -7.07 0.443 33 0.562 -92
6.0 0.414 36 -0.02 0.997 -26 -4.78 0.577 16 0.498 -120
7.0 0.457 22 -0.60 0.933 -40 -2.97 0.711 -4 0.401 -156
8.0 0.496 10 -1.00 0.891 -55 -1.84 0.809 -26 0.344 154
9.0 0.531 -4 -1.42 0.849 -70 -1.37 0.854 -49 0.374 105
10.0 0.573 -19 -1.89 0.805 -85 -1.44 0.847 -69 0.441 67
11.0 0.633 -28 -2.40 0.759 -95 -2.03 0.792 -88 0.516 38
12.0 0.696 -38 -3.32 0.682 -113 -2.63 0.739 -105 0.624 8
AT-41532 Typical Noise Parameters,
Common Emitter, ZO = 50 Ω, VCE = 5 V, IC = 5 mA
Freq.
GHz
Fmin
dB
Γopt Rn
ohms
Gassoc
dBMag Ang
0.9 1.1 0.29 110 7.0 14.8
1.8 1.4 0.41 -167 3.9 11.3
2.0 1.5 0.44 -153 4.7 10.5
2.5 1.7 0.53 -127 9.3 9.3
3.0 1.9 0.60 -106 18.6 8.4
3.5 2.2 0.67 -86 36.8 7.5
4.0 2.4 0.71 -70 59.5 6.7
gmax
dB(S|2,1|)
k
-5
25
15
20
5
0
10
0 21 3 4 5 6
GAIN (dB)
0
1.2
0.8
1
0.2
0.4
0.6
k
FREQUENCY (GHz)
Figure 14. Gain vs. Frequency at 5 V, 5 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
10
AT-41532 Typical Scattering Parameters, Common Emitter, ZO = 50 Ω, VCE = 5 V, IC = 10 mA
Freq.
GHz
S11 S21 S12 S22
Mag Ang dB Mag Ang dB Mag Ang Mag Ang
0.5 0.239 -113 18.69 8.601 98 -28.05 0.040 69 0.641 -18
0.75 0.182 -140 15.51 5.966 86 -25.18 0.055 70 0.611 -19
1.0 0.160 -162 13.20 4.571 78 -22.94 0.071 71 0.597 -20
1.5 0.155 164 9.95 3.144 63 -19.50 0.106 69 0.585 -26
2.0 0.167 140 7.75 2.440 51 -16.89 0.143 66 0.578 -33
3.0 0.201 105 4.87 1.751 29 -12.90 0.226 57 0.566 -49
4.0 0.246 76 3.05 1.421 9 -9.80 0.324 45 0.553 -67
5.0 0.306 54 1.79 1.229 -10 -7.24 0.434 31 0.523 -88
6.0 0.369 40 0.86 1.105 -26 -5.11 0.555 14 0.461 -115
7.0 0.430 27 0.23 1.027 -42 -3.33 0.682 -5 0.366 -149
8.0 0.489 14 -0.35 0.961 -58 -2.11 0.785 -26 0.308 161
9.0 0.539 -1 -0.91 0.900 -73 -1.49 0.842 -47 0.342 110
10.0 0.588 -16 -1.58 0.834 -88 -1.45 0.846 -68 0.419 70
11.0 0.638 -29 -3.09 0.701 -102 -1.93 0.801 -88 0.501 40
12.0 0.713 -38 -3.24 0.689 -115 -2.58 0.743 -104 0.616 9
gmax
dB(S|2,1|)
k
0
25
15
20
5
10
0 21 3 4 5 6
GAIN (dB)
0
1.25
0.75
1
0.25
0.5
k
FREQUENCY (GHz)
Figure 15. Gain vs. Frequency at 5 V, 10 mA.
Note: dB(|S 21|) = 20 * log(|S21|)
gmax = maximum available gain (MAG) if k > 1
gmax = maximum stable gain (MSG) if k < 1
k = stability factor
MAG = S21 (k± √k2–1)
S12
MSG = |S21| /|S12|
k = 1 – |S11|2 – |S22|2 + |D|2 ; D = S11S22 – S12S21
2*|S12| |S21|
11
INPUT
Zo
Zo
C1
C4
C2
L2
R1 VCC = 5.25 V
R2 R4 C5
R5
L3 C4
C3
R6
Q1
L1
R3
OUTPUT
Figure 16. Schematic Diagram.
AT-41532 Application Information
The AT-41532 is described in a low noise amplier for use
in the 800 to 900 MHz frequency range. The amplier is
designed for use with .032 inch thickness FR-4 printed
circuit board material.
900 MHz LNA Design
The amplier is designed for a VCE of 5 volts and IC of 5
mA. and a minimum power supply voltage of 5.25 volts.
Higher power supply voltages will require an additional
resistance to be inserted at the power supply terminal.
The amplier schematic is shown in Figure 16.
A component list is shown in Figure 17. The artwork
including component placement is shown in Figure 18.
Figure 18. 1X Artwork showing Component Placement.
The input matching network uses a series inductor for the
noise match. Some ne tuning for lowest noise gure and
improved input VSWR can be accomplished by adding
capacitance at C2. The shunt C is accomplished with an
open circuited stub while a chip inductor is used for the
series element. The output impedance matching network
is a high pass structure consisting of a series capacitor and
shunt inductor. A resistor is paralleled across the shunt
inductor to enhance broad band stability through 10 GHz.
Bias insertion is accomplished through the use of the
shunt inductor appropriately bypassed. Surface mount
Coilcraft inductors were chosen for their small size.
Biasing
The bias network is designed for a nominal power supply
voltage of 5.25 volts. Resistors R1 and R2 are used to
adjust collector current. Resistor R4 can be attached to the
junction of R5 and C5 to improve bias point stability.
C1,C4 10 pF chip capacitor
C2 Open circuited stub – see text
C3 2.7 pF chip capacitor
C5 1000 pF chip capacitor
L1 8 nH chip inductor (Coilcraft 1008CS-080)
L2 Optional (see R1)
L3 15 nH chip inductor (Coilcraft 1008CS-150)
Q1 Avago AT-41532 Silicon Bipolar Transistor
R1 10K Ω chip resistor (may want to substitute a
180 nH chip inductor and 50 Ω resistor for
lower noise gure , better low freq stability,
then readjust R2)
R2 48 K Ω chip resistor (adjust for rated Ic)
R3 3.32 K Ω chip resistor
R4 3.32 K Ω chip resistor
R5 51.1 Ω chip resistor
R6 1.1K Ω chip resistor (see text)
Zo 50 Ω microstripline
Figure 17. Component Parts List.
IN OUT
Vcc
AT-3XX32
AT-4XX32
01/98 AJW
.062 FR-4
6
16
8
10
12
14
500 700600 800 900 1000
GAIN (dB)
FREQUENCY (MHz)
Figure 17. AT-41532 Gain vs. Frequency.
1
1.6
1.1
1.2
1.3
1.4
500 700600 800 900 1000
NOISE FIGURE
(dB)
FREQUENCY (MHz)
Figure 18. AT-41532 Noise Figure vs. Frequency.
1.5
-14
0
Input
Output
-10
-12
-8
-4
500 700600 800 900 1000
RETURN LOSS (dB)
FREQUENCY (MHz)
Figure 19. Input/Output Return Loss.
-6
-2
Figure 19. Gain vs Frequency. Figure 20. Noise Figure vs Frequency. Figure 21. Input/Output Return Loss.
Performance
The measured gain of the completed amplier is shown in
Figure 19. The gain varies
from 14 to 15 dB over the 800 to 900 MHz frequency
range. Noise gure versus frequency is shown in Figure
20. Best performance occurs at 850 MHz providing a near
1 dB noise gure.
Measured input and output return loss is shown in Figure
21. The input return loss is 10 dB at 850 MHz and can be
improved with slight tuning at C2. Output return loss was
measured at almost 10 dB at 850 MHz.
There is considerable tuning interaction between input
and output matching networks in any single stage
amplier. Having a somewhat better input return loss co-
incident with low noise gure may necessitate a compro-
mise in output return loss.
Output intercept point, IP3, was measured at 850 MHz to
be +12 dBm. Removing the 1.1 KΩ resistor at R6 increases
IP3 to +13.6 dBm. Resistor R6 was originally added to
enhance stability; caution is urged when removing this
resistor or increasing its value without careful analysis.
Another alternative to the shunt resistor R6 would be to
incorporate a resistor in series with the transistor collector
lead. This resistor would be in the 10 to 27Ω range and
has similar eects on circuit stability. A third alternative
is to re-optimize the output match for power as opposed
to matching for lowest output VSWR. This may make the
output return loss less than 10 dB but it would enhance
power output.
Modications to Original Demo Board
The original demo board dated 01/98 requires some
modication to work as described in this application note.
The modication is to add resistor R6 in series with the
collector lead. This is accomplished by cutting the etch at
the output of Q1 such that resistor R6 can be placed on
the circuit board as shown in Figure 17. Inductor L3 will
then have be placed at a 90 degree angle with respect to
its original intended location. L3 is then connected to the
junction of R6 and L4 with a small piece of wire or etch.
Using the AT-41532 at Other Frequencies
The demo board and design techniques presented here
can be used to build low noise ampliers for other fre-
quencies in the VHF through 1.9 GHz frequency range.
Ordering Information
Part Numbers No. of Devices Comments
AT-41532-BLK 100 Bulk
AT-41532-BLKG 100 Bulk
AT-41532-TR1 3000 7" Reel
AT-41532-TR1G 3000 7" Reel
AT-41532-TR2 10000 13" Ree
AT-41532-TR2G 10000 13" Reel
Note: Order part number with a “G” sux if lead-free option is desired.
Package Dimensions
SOT-323 Plastic Package
e
B
e1
E1
C
EXXX
L
D
A
A1
Notes:
XXX-package marking
Drawings are not to scale
DIMENSIONS (mm)
MIN.
0.80
0.00
0.15
0.08
1.80
1.10
1.80
0.26
MAX.
1.00
0.10
0.40
0.25
2.25
1.40
2.40
0.46
SYMBOL
A
A1
B
C
D
E1
e
e1
E
L
1.30 typical
0.65 typical
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Data subject to change. Copyright © 2005-2009 Avago Technologies. All rights reserved. Obsoletes 5989-2650EN
AV02-1964EN - June 9, 2009
Tape Dimensions and Product Orientation
For Outline SOT-323 (SC-70 3 Lead)