New Gain Blocks Have High Gain, Broadband Performance
New Gain Blocks Have High Gain, Broadband Performance Summary Celeritek has added two new products; the CGB7014 and the CGB7017, to its successful family of InGaP HBT-based gain blocks. These products feature high gain, broad bandwidth, and a low price. The CGB 7014, with a Vs of 8V, exhibits 23 dB of gain at 2 GHz, and 18.5 dB of gain at 6 GHz, and the CGB 7017, with a Vs of 5V, exhibits 22 dB of gain at 2 GHz, and 19.5 dB of gain at 6 GHz. The parts are available in SOT-89 packages. These parts do not require matching, but, on the CGB7017, the gain vs. frequency characteristic can be flattened with the addition of a simple output match. As with all of Celeritek’s gain blocks, these new parts have excellent ESD resistance and testability.
Gain (dB), P1dB (dBm), and OIP3 (dBm)
Darlington-pair based gain blocks have been in use for more than 50 years, in a variety of applications. Most gain blocks feature either high gain and large gain slope vs. frequency, or low gain and small gain slope vs. frequency. The CGB 7014 and 7017, provide high, flat gains, especially from 3 to 6 GHz. The gain vs frequency characteristic of the CGB7017 can be flattened further through the addition of a simple output match. With this match, and using appropriate choke and bypass components, gain from 20 MHz to 3.5 GHz, over the temperature range –40C to 85C, is typically 20.5 +/- 0.75 dB. From 20 MHz to 6 GHz, over the –40 C to 85 C temperature range, gain is 20 +/- 1.5 dB, as shown in figure 2. At frequencies up to 2.5 GHz, gain variation of the CGB7017-SC at a given frequency is less than +/- 0.1 dB, from –40C to 85C, with or without the output matching circuitry.
40 OIP3
35 30
25 C -Gain
CGB7014-SC
-40 C -Gain 85 C - Gain
SS Gain
25
25 C - P1dB -40 C - P1dB
20
85 C - P1dB
P1dB
15
-40 C - OIP3 25C - OIP3
10
85C - OIP3
5 0
2
4
6
8
Frequency (GHz) Fig. 1a CGB 7014-SC Gain, P1dB, and OIP3 Vs Frequency
Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 1 of 4
Gain (dB), P1dB (dBm), and OIP3, (dBm)
New Gain Blocks Have High Gain, Broadband Performance (cont.)
40 35
OIP3
25 C - Gain -40 C - Gain 85 C -Gain 25 C - P1dB -40 C - P1dB 85 C - P1dB -40 C - OIP3 25C - OIP3 85C - OIP3
CGB7017-SC
30 SS Gain
25 20
P1dB
15 10 5 0
2
4
6
8
Frequency (GHz)
Gain (dB), P-1dB (dBm), and OIP3 (dBm)
Fig. 1b CGB 7017-SC Gain, P1dB, and OIP3 Vs Frequency (Without Output Match)
35
OIP3
CGB7017-SC W/ Output Match
-40C - Gain
30
25C - Gain 85C - Gain
25
-40C - P-1dB
SS Gain
20
25C - P-1dB 85 C - P-1dB
P1dB
-40C - OIP3 25C - OIP3
15
85C - OIP3
10 0
1
2
3
4
5
6
Frequency (GHz) Fig. 2 Gain, P1dB, and OIP3 Vs. Frequency for the CGB7017-SC with Output Match. Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 2 of 4
New Gain Blocks Have High Gain, Broadband Performance (cont.) The schematic of the circuit used to achieve the above performance is shown below. Appropriate attention to the physical size and Q factors of the passive components is necessary to achieve optimum broadband performance.
R Bias_Resistor R=8.5 Ohm C Bypass_Cap C=1 uF C Bypass_Cap1 C=1000 pF L Choke_Inductor L=470 nH CGB7017-SC
RFin
V_DC SRC1 Vdc=5 V
C C Output_Block_Cap Output_Block_Cap1 C=1000 pF C=1000 pF
C Input_Block_Cap Amplifier C=1000 pF AMP1
Note: Capacitors are 0805 SMT, Choke inductor is 0805 wirewound. Match inductor is 0603 wirewound. Match resistor is 0603 +/- 1% Bias Resistor is 1206 1/4 W.
RFout
L Match_Ind L=6.8 nH
R Match_Res R=75 Ohm
Fig. 3 Schematic for Circuit used to Achieve Performance Shown in Fig. 2. A Note on Stability: The CGB7014 and CGB7017 are unconditionally stable under small signal conditions, from –40 to 85 C. To guarantee stability over the –40 to 85C temp range when Pout is greater than 14 dBm for the CGB7017, or greater than 17 dBm for the CGB7014, it is recommended that the load being driven by these amplifiers have the following return loss characteristics: For frequencies < 1 GHz, the load for the CGB7014 should have an input return loss of >5 dB; the load for the CGB7017 should have an input return loss >10dB. For frequencies, >1 Ghz, and < 2 GHz, the load for the CGB7014 should have a return loss >3 dB, and the load for the CGB7017 should have a return loss > 5 dB. Above 2 GHz, the CGB7014 is unconditionally stable for all output powers. The CGB7017 is unconditionally stable at all output powers at frequencies above 3.5 GHz. Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 3 of 4
New Gain Blocks Have High Gain, Broadband Performance (cont.) Conclusion Two new members have been added to Celeritek’s CGB 7000 family of gain blocks. The CGB7014-SC and CGB7017-SC provide high flat gain over frequency bands as wide as 20 MHz to 6 GHz. These parts are ideal for instrumentation, fiber optic drivers and receivers, and a variety of wireless and wireline amplifiers.
Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 4 of 4
Gain (dB), P1dB (dBm), and OIP3 (dBm)
Darlington-pair based gain blocks have been in use for more than 50 years, in a variety of applications. Most gain blocks feature either high gain and large gain slope vs. frequency, or low gain and small gain slope vs. frequency. The CGB 7014 and 7017, provide high, flat gains, especially from 3 to 6 GHz. The gain vs frequency characteristic of the CGB7017 can be flattened further through the addition of a simple output match. With this match, and using appropriate choke and bypass components, gain from 20 MHz to 3.5 GHz, over the temperature range –40C to 85C, is typically 20.5 +/- 0.75 dB. From 20 MHz to 6 GHz, over the –40 C to 85 C temperature range, gain is 20 +/- 1.5 dB, as shown in figure 2. At frequencies up to 2.5 GHz, gain variation of the CGB7017-SC at a given frequency is less than +/- 0.1 dB, from –40C to 85C, with or without the output matching circuitry.
40 OIP3
35 30
25 C -Gain
CGB7014-SC
-40 C -Gain 85 C - Gain
SS Gain
25
25 C - P1dB -40 C - P1dB
20
85 C - P1dB
P1dB
15
-40 C - OIP3 25C - OIP3
10
85C - OIP3
5 0
2
4
6
8
Frequency (GHz) Fig. 1a CGB 7014-SC Gain, P1dB, and OIP3 Vs Frequency
Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 1 of 4
Gain (dB), P1dB (dBm), and OIP3, (dBm)
New Gain Blocks Have High Gain, Broadband Performance (cont.)
40 35
OIP3
25 C - Gain -40 C - Gain 85 C -Gain 25 C - P1dB -40 C - P1dB 85 C - P1dB -40 C - OIP3 25C - OIP3 85C - OIP3
CGB7017-SC
30 SS Gain
25 20
P1dB
15 10 5 0
2
4
6
8
Frequency (GHz)
Gain (dB), P-1dB (dBm), and OIP3 (dBm)
Fig. 1b CGB 7017-SC Gain, P1dB, and OIP3 Vs Frequency (Without Output Match)
35
OIP3
CGB7017-SC W/ Output Match
-40C - Gain
30
25C - Gain 85C - Gain
25
-40C - P-1dB
SS Gain
20
25C - P-1dB 85 C - P-1dB
P1dB
-40C - OIP3 25C - OIP3
15
85C - OIP3
10 0
1
2
3
4
5
6
Frequency (GHz) Fig. 2 Gain, P1dB, and OIP3 Vs. Frequency for the CGB7017-SC with Output Match. Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 2 of 4
New Gain Blocks Have High Gain, Broadband Performance (cont.) The schematic of the circuit used to achieve the above performance is shown below. Appropriate attention to the physical size and Q factors of the passive components is necessary to achieve optimum broadband performance.
R Bias_Resistor R=8.5 Ohm C Bypass_Cap C=1 uF C Bypass_Cap1 C=1000 pF L Choke_Inductor L=470 nH CGB7017-SC
RFin
V_DC SRC1 Vdc=5 V
C C Output_Block_Cap Output_Block_Cap1 C=1000 pF C=1000 pF
C Input_Block_Cap Amplifier C=1000 pF AMP1
Note: Capacitors are 0805 SMT, Choke inductor is 0805 wirewound. Match inductor is 0603 wirewound. Match resistor is 0603 +/- 1% Bias Resistor is 1206 1/4 W.
RFout
L Match_Ind L=6.8 nH
R Match_Res R=75 Ohm
Fig. 3 Schematic for Circuit used to Achieve Performance Shown in Fig. 2. A Note on Stability: The CGB7014 and CGB7017 are unconditionally stable under small signal conditions, from –40 to 85 C. To guarantee stability over the –40 to 85C temp range when Pout is greater than 14 dBm for the CGB7017, or greater than 17 dBm for the CGB7014, it is recommended that the load being driven by these amplifiers have the following return loss characteristics: For frequencies < 1 GHz, the load for the CGB7014 should have an input return loss of >5 dB; the load for the CGB7017 should have an input return loss >10dB. For frequencies, >1 Ghz, and < 2 GHz, the load for the CGB7014 should have a return loss >3 dB, and the load for the CGB7017 should have a return loss > 5 dB. Above 2 GHz, the CGB7014 is unconditionally stable for all output powers. The CGB7017 is unconditionally stable at all output powers at frequencies above 3.5 GHz. Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 3 of 4
New Gain Blocks Have High Gain, Broadband Performance (cont.) Conclusion Two new members have been added to Celeritek’s CGB 7000 family of gain blocks. The CGB7014-SC and CGB7017-SC provide high flat gain over frequency bands as wide as 20 MHz to 6 GHz. These parts are ideal for instrumentation, fiber optic drivers and receivers, and a variety of wireless and wireline amplifiers.
Company Proprietary ©2005 All Rights Reserved
Mimix Broadband, Inc., 10795 Rockley Rd., Houston, Texas 77099 Tel: 281.988.4600 Fax: 281.988.4615 mimixbroadband.com
Page 4 of 4
