Philips Semiconductors | Application note | |
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Using the NE/SA5234 amplifier | AN1651 | |
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VCC |
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| R82 | R85 | R76 |
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IB2 | IB5 | IB6 | Q83 | Q85 |
| Q81 |
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IB4 |
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| IB8 |
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± |
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| Q82 |
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I2 | Q53,54 |
| Q84 |
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| Q51,52 |
| C5 |
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| C3 |
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INPUT |
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| OUTPUT |
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| Q72 | C6 |
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+ | C2 |
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I1 |
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| Q78 |
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| Q71 |
| Q61 | Q62 |
| Q75 | ||
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| VB4 |
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| D3 |
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| C1 | CLASS |
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| IB3 | AB |
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| CONTROL | IB9 | R86 | R75 |
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VEE |
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INTERMEDIATE STAGE | CURRENT CONTROL | CLASS AB OUTPUT | SL00632 |
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Figure 4.
| 100 |
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| 80 |
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dB | 60 |
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G1000 |
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| 40 |
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| 20 |
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| 0 |
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| 10Hz | 100Hz | 1kHz | 10kHz | 100kHz | 1MHz |
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| FREQUENCY |
| 10 106 |
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| SL00633 |
Figure 5. NE5234 Closed Loop Gain vs Frequency
1991 Oct | 4 |
