I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and resistorvoltage divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this?
I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and resistor divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this?
I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and voltage divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this?
Mahendra Gunawardena
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why Why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice?
I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and resistor divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this? Thanks a lot!
why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice?
I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and resistor divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this? Thanks a lot!
Why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice?
I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and resistor divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this?
why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice?
I'm trying to simulate a biased emitter follower in LTspice. The dc operating point seems to be wrong once I used a DC coupled sine input signal(zero offset, 5V amplitude, 60Hz), it is almost 0V at emitter follower's output. Once I place a capacitor between sine input and resistor divider(make the input signal ac coupled) the dc operating point makes sense, it is about 7.5V, half the supply voltage. I think there is no difference for a zero offset sine input signal to be ac or dc coupled. So why a DC coupled sine input signal will make my biased emitter follower looks like unbiased in LTspice? Is it just simulation behavior or in real life it actually behaves like this? Thanks a lot!