Update Content - 2020-10-20

content/zettels/charge_amplifiers.md

@@ -4,6 +4,10 @@ author = ["Thomas Dehaeze"]
 draft = false
 +++
 
+Backlinks:
+
+-   [Signal Conditioner]({{< relref "signal_conditioner" >}})
+
 Tags
 : [Electronics]({{< relref "electronics" >}})
 
@@ -15,6 +19,24 @@ A charge amplifier outputs a voltage proportional to the charge generated by a s
 This can be typically used to interface with piezoelectric sensors.
 
 
+## Basic Circuit {#basic-circuit}
+
+Two basic circuits of charge amplifiers are shown in Figure [1](#org9ffcf40) (taken from ([Fleming 2010](#orgaceef58))) and Figure [2](#org37bd87f) (taken from ([Schmidt, Schitter, and Rankers 2014](#org683b96e)))
+
+<a id="org9ffcf40"></a>
+
+{{< figure src="/ox-hugo/charge_amplifier_circuit.png" caption="Figure 1: Electrical model of a piezoelectric force sensor is shown in gray. The op-amp charge amplifier is shown on the right. The output voltage \\(V\_s\\) equal to \\(-q/C\_s\\)" >}}
+
+<a id="org37bd87f"></a>
+
+{{< figure src="/ox-hugo/charge_amplifier_circuit_bis.png" caption="Figure 2: A piezoelectric accelerometer with a charge amplifier as signal conditioning element" >}}
+
+The input impedance of the charge amplifier is very small (unlike when using a voltage amplifier).
+
+The gain of the charge amplified (Figure [1](#org9ffcf40)) is equal to:
+\\[ \frac{V\_s}{q} = \frac{-1}{C\_s} \\]
+
+
 ## Manufacturers {#manufacturers}
 
 | Manufacturers   | Links                                                                                                                                         | Country |
@@ -28,4 +50,9 @@ This can be typically used to interface with piezoelectric sensors.
 | Sinocera        | [link](http://www.china-yec.net/instruments/signal-conditioner/multi-channels-charge-amplifier.html)                                          | China   |
 | L-Card          | [link](https://en.lcard.ru/products/accesories/le-41)                                                                                         | Rusia   |
 
-<./biblio/references.bib>
+
+## Bibliography {#bibliography}
+
+<a id="orgaceef58"></a>Fleming, A.J. 2010. “Nanopositioning System with Force Feedback for High-Performance Tracking and Vibration Control.” _IEEE/ASME Transactions on Mechatronics_ 15 (3):433–47. <https://doi.org/10.1109/tmech.2009.2028422>.
+
+<a id="org683b96e"></a>Schmidt, R Munnig, Georg Schitter, and Adrian Rankers. 2014. _The Design of High Performance Mechatronics - 2nd Revised Edition_. Ios Press.