| Part Numbert | Mfg | Packt | D/C | Descriptiont | Qty | Company/Contact | |
| STM3488B1 | ST | DIP | 885 |
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| STM3488B1 | ST | DIP | 08+ | 6000 |
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| STM3488B1 | 885 | ST | DIP |
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STM3488B1 Datasheet
STM3488B1 Price Each VCA is a current input, current output type, whose cucrent gain is controjled from less than -96dB to unity with the controJ voltage. It will be noted that, in order to Et two completely independent VCAs in an 8 pin minidip, the reference voltage for the two controlinputs is made equal to the volt- age at the output ofVCA2 (pin 7) through a high input impedance buffer. Thus, it is mandatory that VCA2 0utput drive a node which is at a constant DC level, typically O volts (any AC component should be well under lmV.P.P.). This requirement is most easily met by feeding the output into the summing node ofan op amp, which is also senring to convert the output current to a volta{;e. Although the bias current to the intemal buffer will generate a constant D.C. offset at the output ofthis op amp, the amount is so small (typically< 5mV) thatit can usually be ignored. STM3488B1 on stock VOLPNOLV arid VOHPNOHV: Determine the quiet output pin that demonstrates the greatest noise levels. The worst case pin will usually be the furthest from the ground pin. Monitor the output volt- ages using a sol coaxial cable plugged into a standard SMB type connector on the test fixture. Do not use an active FET probe. Measure VOLP and VOLV on the quiet output during the worst case transition for active and enable. Measure VOHP and VOHV on the quiet output during the worst case active and enable transition. Verify that the GND reference recorded on the oscillo- scope has not drifted to ensure the accuracy and repeat- ability of the measurements. VILD and VIHD: Monitor one of the switching outputs using a 50 I coaxial cable plugged into a standard SMB type connector on the test fixture. Do not use an active FET probe. First increase the input LOW voltage level, VIL, until the output begins to oscillate or steps out a min of 2 ns. Oscillation is defined as noise on the output LOW level that exceeds VIL limits, or on output HIGH levels that exceed VIH limits. The input LOW voltage level at which oscillation occurs is defined as VILD. Next decrease the input HIGH voltage level, VIH, until the output begins to oscillate or steps out a min of 2 ns. Oscillation is defined as noise on the output LOW level that exceeds VIL limits, or on output HIGH levels that exceed VIH limits. The input HIGH voltage level at which oscillation occurs is defined as VIHD. Verify that the GND reference recorded on the oscillo- scope has not drifted to ensure the accuracy and repeat- ability of the measurements vcc
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