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Started by aron, February 06, 2009, 06:40:30 PM
Quote from: "Rob A"Kind of a puzzler--if it were an opamp you'd kind of expect back-to-back 9V. The only audio amp IC I can quickly recall that runs single-sided supply (LM386) is not exactly audiophile material.You think that's what we're looking at? I love how it's zip-tied in the socket.
Quote from: Tim W on February 10, 2009, 12:24:48 PMThe secret to using an opamp with a unipolar power supply is all in the DC biasing. One can bias an opamp running from one 9V battery with half the supply voltage using a resistive voltage divider. Now, the opamp's 'ground' reference is actually at 4.5V. Blocking caps are used on the input and output of the signal path to allow for 'bipolar' signals... recentering them DC-wise around 4.5V for the opamp.