included some more details as requested

diff --git a/electronics/electronics2013.pdf b/electronics/electronics2013.pdf
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Binary files a/electronics/electronics2013.pdf and b/electronics/electronics2013.pdf differ

diff --git a/electronics/electronics2013.tex b/electronics/electronics2013.tex
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--- a/electronics/electronics2013.tex
+++ b/electronics/electronics2013.tex
@@ -49,21 +49,30 @@ one converter board. The cables can be made in any length, so we can do studies
 length. \final{The final setup will most likely use different cables with better shielding and
 improved handling.} Cables as well as connectors will be bought by GSI.
 
+Table \ref{iocount} gives a rough count of necessary I/O. The final number of connections required
+will strongly depend on the realisation of the converter board, mainly with respect to the data
+busses for switches and ADCs. A.t.m. there are 14 I/O per converter board plus 12 I/O per sensor.
+Note that this setup is for M26 sensors only where we will not have any ladders larger than 2
+sensors. The number of I/O for the final sensor will be different.
+
 \begin{table}[htp]
  \centering
-\begin{tabularx}{\textwidth}{X|c|c}
-\textbf{Purpose} & \textbf{Inputs} & \textbf{Outputs}  \\
+\begin{tabularx}{\textwidth}{X|c|c|c|c}
+ & \multicolumn{2}{c|}{\textbf{per Ladder}} & \multicolumn{2}{c}{\textbf{per
+Sensor}} \\
+\textbf{Purpose} & \textbf{Inputs} & \textbf{Outputs} & \textbf{Inputs} & \textbf{Outputs}  \\
 \hline
-JTAG: TDI,TMS,TCK, TDO& 1 & 3 \\
-Sensor Data: Clock, Marker, 2x Data per sensor & 8 & 0 \\
-Sensor Control: Clock, Start, Reset. & 0 & 3 / 1+2 \\
-ADC for voltages and currents (SPI) & 4 & 3 \\
-Voltage and JTAG switch (Bus) & 0 & 6 / 0+6 \\
+JTAG: TDI,TMS,TCK, TDO & 1 & 3 & 0 & 0\\
+Sensor Data: Clock, Marker, 2x Data per sensor & 0 & 0 & 8 & 0\\
+Sensor Control: Clock, Start, Reset. & 0 & 3 (2) & 0 & 0\\
+ADC for voltages and currents (SPI) & 0 & 3 & 2 & 1 (1)\\
+Voltage and JTAG switch (Bus) & 0 & 4 (4) & 0 & 1 (1) \\
 \hline
-Total & 13 & 15 / 7+8\\
+Total & 1 & 13 (6) & 10 & 2 (2)\\
 \end{tabularx}
-\caption{Inputs/Outputs from the FPGA for a converter board with 2 sensors. First value
-differential, second single ended}
+\caption{Inputs/Outputs from the FPGA to the converter board. The number in
+parantheses shows the number of I/O that could be replaced by a non-differential connection.}
+\label{iocount}
 \end{table}
 
 
@@ -80,17 +89,30 @@ of them.
 
 \subsection{Voltage and Current Monitoring}
 All voltages and currents should be monitored. These are three supply voltages and currents per
-sensor, the 8 internally generated bias voltages and the temperature.
-The temperature measurement needs an external differential amplification.
+sensor (i.e. analog and digital VDD as well as the clamping voltage), the 8 internally generated
+bias voltages and the temperature.
+
+The temperature measurement needs an external differential amplification. The signal of the
+temperature diode can only be measured using a sense line for the actual ground level on the sensor
+with a dedicated sense wire. The amplifier has to work on the difference between this ground sense
+wire and the output of the temperature diode. This could also be implemented using a differential
+ADC channel.
+
+The 8 VDiscr signals must be monitored both single ended and differential\footnote{The voltages
+are labeled 1A-1D and 2A-2D. We need both the absolute value of the voltages ($\approx$2V) as well
+as the differences between 1A-2A, 1B-2B etc. These are in the order of $\pm$ 32 mV.}. I.e. must use
+a ADC that can switch input pairs from single ended to differential and provides a selectable input
+amplification of 20 - 50.
+
+In total, 7 single ended plus 4 differential ADC channels are needed per sensor. If two 8-channel
+ADC are used, the remaining channel can be connected to the ground sense wire.
+
+The on-board ADC should provide about 1 MSPS and a SPI (or similar) interface. AD7928 is a
+possible candidate for single ended measurement.
+(I do not have a differential ADC in mind yet, but the ADC implemented in Attiny microcontrollers
+does fit the requirements despite conversion speed.)
 
-The 8 VDiscr signals must be monitored both single ended and differential. I.e. must use a ADC that
-can switch input pairs from single ended to differential and provides a selectable input
-amplification of 50 - 100. In total, 7 single ended plus 4 differential ADC channels are needed per
-sensor.
 
-The on-board ADC should provide at least 1 MSPS and a SPI (or similar) interface. AD7928 is a
-possible candidate for single ended measurement. It can also provide the differential measurements
-if a pre-amplification stage with OpAmps is included if a dedicated ADC is not available.
 If necessary, an external monitoring board or oscilloscope can be connected for testing purposes.
 Such a TRB3-AddOn is currently in preparation at GSI (52 channels, 12 Bit, 40 MSPS).  
 
@@ -115,7 +137,7 @@ with a slow but precise DAC.
 
 
 \subsection{Connectivity}
-All communication to the TRB3 should be differential, maybe despite on some static signals. Test
+All communication to the TRB3 should be differential, maybe despite some static signals. Test
 pads for most signals should be added to connect external, more precise instruments.
 
 All signals from and to the sensor should be fed through LVDS buffers to reduce the load on the
@@ -152,6 +174,8 @@ not viable with the current bonding / cable set-up.
 
 \clearpage
 \section{Front-end Board (FEB)}
+The form-factor of the FEB will be similar to the current one, without the two connectors on the
+short sides and with an additional broad connector on the side towards the CB.
 
 \subsection{Jtag}
 The switches for bridging of sensors will be located on the CB as before, so no active