Hello,
Having a 50uF or larger capacitance at the outputs of the BUF12840 is not recommended and can very likely cause severe issues. These issues may manifest in the form of instability, like oscillation and incorrect DC voltages at the output, or in the form of higher susceptibility to electrical overstress (EOS).
As described in p.22 of the BUF12840 data sheet, large external capacitors can store significant charge when the output voltages are active. If the power to the BUF12840 is removed, the outputs will turn off, and the difference in potential now present will cause capacitor will discharge back into the BUF12840 through the output ESD diodes. This current can cause fatal damage to the device and must be protected against by placing a Schottky diode at each output with large capacitance, as shown in Figure 24 of the BUF12840 data sheet. A current-limiting resistor in series with the output pin is also recommended, but keep in mind that this will act as a divider with any load resistance present and must be sized accordingly.
The recommended value of output capacitance, most simply, is as low as possible. The larger the capacitor, the more charge that can be stored and the higher risk of EOS damage is present.
Best regards,
Ian Williams
Linear Applications Engineer
Precision Analog - Op Amps
