Op-amp Varieties

Summing Amplifier

求和放大器

This is an example of an inverting amplifier of gain=1 with multiple inputs. More than two inputs can be used, for example in an audio mixer circuit. The input resistors can be unequal, giving a weighted sum.

这是一个增益为1的反相放大器示例，具有多个输入。可以使用超过两个输入，例如在音频混音器电路中。输入电阻可以不相等，从而产生加权和。

Rules application

规则应用

Applications

应用

	Menu 菜单
	Summing amplifier 求和放大器
	Difference amplifier 差分放大器
	Differential amplifier 差分放大器

Rule Application:Summing Amplifier

规则应用：加法放大器

The behavior of most configurations of op-amps can be determined by applying the "golden rules". For the summing amplifier by the current rule the non-inverting input is a virtual ground. Then the current into A must be zero. This requires

大多数运算放大器的特性可通过应用“黄金规则”来确定。对于求和放大器而言，根据电流规则，同相输入端是一个虚拟接地点。因此，流入A的电流必须为零。这要求

Hence

因此

Applications: Summing Amplifier

应用：加法放大器

The summing amplifier" is a versatile device for combining signals. It can either add signals directly, or scale them to fit some predetermined combination rule.

求和放大器是一种多功能的信号组合设备。它可以直接加信号，或者按照某种预设的组合规则对信号进行缩放。

Summing several signals with equal gains is done in an audio mixer.
在音频混音器中，几个具有相同增益的信号被相加。
A summing amplifier with different resistors on the inputs gives a weighted sum. This can be used to convert a binary number to a voltage in a digital-to-analog converter.
具有不同输入电阻的求和放大器可以实现加权求和。这可以用于将二进制数转换为电压，从而在数字-模拟转换器中实现。
A summing amplifier can be used to apply a DC offset voltage along with an AC signal voltage. This is done in a LED modulation circuit to keep the LED in its linear operating range.
求和放大器可用于同时施加一个直流偏置电压和一个交流信号电压。这在LED调制电路中用于将LED保持在其线性工作范围内。