RCA 3040 wideband amplifier
AC response of an 11-transistor wideband amplifier to 10GHz.
The RCA 3040 wideband amplifier, a classic Berkeley benchmark. The .control block finds the ac response from 1Hz to 10GHz and prints the gain at node 16.
- vdb(16)
Output
rca3040 ckt - rca 3040 wideband amplifier
AC Analysis Tue Sep 29 08:47:04 2026
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Index frequency vdb(16)
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0 1.000000e+00 4.095454e+01
1 1.258925e+00 4.095454e+01
2 1.584893e+00 4.095454e+01
3 1.995262e+00 4.095454e+01
4 2.511886e+00 4.095454e+01
5 3.162278e+00 4.095454e+01
6 3.981072e+00 4.095454e+01
7 5.011872e+00 4.095454e+01
8 6.309573e+00 4.095454e+01
9 7.943282e+00 4.095454e+01
10 1.000000e+01 4.095454e+01
11 1.258925e+01 4.095454e+01
12 1.584893e+01 4.095454e+01
13 1.995262e+01 4.095454e+01
14 2.511886e+01 4.095454e+01
15 3.162278e+01 4.095454e+01
16 3.981072e+01 4.095454e+01
17 5.011872e+01 4.095454e+01
18 6.309573e+01 4.095454e+01
19 7.943282e+01 4.095454e+01
20 1.000000e+02 4.095454e+01
21 1.258925e+02 4.095454e+01
22 1.584893e+02 4.095454e+01
23 1.995262e+02 4.095454e+01
24 2.511886e+02 4.095454e+01
25 3.162278e+02 4.095454e+01
26 3.981072e+02 4.095454e+01
27 5.011872e+02 4.095454e+01
28 6.309573e+02 4.095454e+01
29 7.943282e+02 4.095454e+01
30 1.000000e+03 4.095454e+01
31 1.258925e+03 4.095454e+01
32 1.584893e+03 4.095454e+01
33 1.995262e+03 4.095454e+01
34 2.511886e+03 4.095454e+01
35 3.162278e+03 4.095454e+01
36 3.981072e+03 4.095454e+01
37 5.011872e+03 4.095454e+01
38 6.309573e+03 4.095454e+01
39 7.943282e+03 4.095454e+01
40 1.000000e+04 4.095454e+01
41 1.258925e+04 4.095454e+01
42 1.584893e+04 4.095454e+01
43 1.995262e+04 4.095454e+01
44 2.511886e+04 4.095453e+01
45 3.162278e+04 4.095453e+01
46 3.981072e+04 4.095453e+01
47 5.011872e+04 4.095452e+01
48 6.309573e+04 4.095451e+01
49 7.943282e+04 4.095450e+01
50 1.000000e+05 4.095447e+01
51 1.258925e+05 4.095443e+01
52 1.584893e+05 4.095437e+01
53 1.995262e+05 4.095427e+01
54 2.511886e+05 4.095412e+01
55 3.162278e+05 4.095387e+01
56 3.981072e+05 4.095348e+01
57 5.011872e+05 4.095287e+01
58 6.309573e+05 4.095189e+01
59 7.943282e+05 4.095034e+01
60 1.000000e+06 4.094789e+01
61 1.258925e+06 4.094399e+01
62 1.584893e+06 4.093781e+01
63 1.995262e+06 4.092800e+01
64 2.511886e+06 4.091240e+01
65 3.162278e+06 4.088757e+01
66 3.981072e+06 4.084793e+01
67 5.011872e+06 4.078442e+01
68 6.309573e+06 4.068204e+01
69 7.943282e+06 4.051563e+01
70 1.000000e+07 4.024214e+01
71 1.258925e+07 3.978705e+01
72 1.584893e+07 3.902350e+01
73 1.995262e+07 3.775306e+01
74 2.511886e+07 3.572779e+01
... (26 more lines)
The circuit: examples/rca3040.cir
rca3040 ckt - rca 3040 wideband amplifier * vin 1 0 sin(0 0.1 50meg 0.5ns) ac 1 vcc 2 0 15.0 vee 3 0 -15.0 rs1 30 1 1k rs2 31 0 1k r1 5 3 4.8k r2 6 3 4.8k r3 9 3 811 r4 8 3 2.17k r5 8 0 820 r6 2 14 1.32k r7 2 12 4.5k r8 2 15 1.32k r9 16 0 5.25k r10 17 0 5.25k q1 2 30 5 qnl q2 2 31 6 qnl q3 10 5 7 qnl q4 11 6 7 qnl q5 14 12 10 qnl q6 15 12 11 qnl q7 12 12 13 qnl q8 13 13 0 qnl q9 7 8 9 qnl q10 2 15 16 qnl q11 2 14 17 qnl * .model qnl npn bf=80 rb=100 ccs=2pf tf=0.3ns tr=6ns cje=3pf + cjc=2pf va 50 * .control *dc vin -0.25 0.25 0.005 *plot v(16) * ac dec 10 1 10g print vdb(16) plot vdb(16) * *tran 2.0ns 200ns *plot v(16) v(17) .endc .end
Run it with spice rca3040.cir, or open it with File › Load netlist in the Qt window. The plots and output above were made by util/mkexamples.py, which runs the deck in batch mode. All examples