LeCroy WaveSurfer 400 Series User Manual

4-4 Theory of Operation
Divide gain
The gain ratio in each block and input range is a table below.
At the BNC the dynamic range is 16 mV to 80V FS (full scale) and the output is 500 mV
differential (HAD631 input).
Range V/div
Block
2mV 5mV 10mV 20mV 50mV 100mV 200mV 500mV 1V 2V 5V 10V
ATT 1/*10
1 1 1 1 1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
ATT 1/*100
1 1 1 1 1 1 1 1 0.1 0.1 0.1 0.1
ATT 1/5
1 1 1 0.2 1 1 0.2 1 1 0.2 0.2 0.2
SA5209D
31.25 12.5 6.25 15.62 1.25 6.25 15.62 1.25 6.25 15.62 6.25 3.125
Total(ratio)
31.25 12.5 6.25 3.125 1.25 0.625 0.3125 0.125 0.0625 0.03125 0.0125 0.00625
Analog control voltage
Circuit name signal level Signal name
CHx OFFSET +/-4V Offset control signal for Front End
CHx GAIN +/-4V SA5209D gain control signal
CHx OS ADJ 0 to +4V Offset control signal for differential amplifiers
INT CAL -6V to +6V Signal each CH commonness for calibration
1 / 10
+12V
R88
0.047uF
400k ohms
1 / 10
Q8
CHx Input
CHx SIG
RL1
2200pF
CHx OFFSET
400k ohms
Q3
high impedance buffer
50 ohms
RL5
DC signal for Over Load
RL6
RL4
800k ohms
to differencial amplifiers
RL4
INT CAL
DC signal for offset level
CHx CAL SIG
CHx OVLD
RL3
Thermistor
RL2
DC signal for DC calibration
CHx GND
Q6
Square wave for skew calibration
1 / 5
Figure 4-3 Front End Block Diagram 1

LeCroy WaveSurfer 400 Series Specifications

General

Brand	LeCroy
Model	WaveSurfer 400 Series
Category	Test Equipment
Language	English