SC5 Signal Conversion Instrument Overview
11
Instrument Overview
Block diagram
The block diagram of the SC5 is shown in the picture below.
Figure 1: Block diagram of the SC5. Only one analog input and one analog output are shown for clarity.
The SC5 can be divided into the following functional blocks: Analog inputs, analog outputs, fast analog output,
logic, and power supply.
Each analog input (AI) uses an instrumentation amplifier frontend, followed by a 5
th
order low-pass filter with a
corner frequency of 100 kHz (-3 dB), and then by an 18-bit 1 MS/s ADC. The ADC circuit uses the same
temperature-stabilized voltage reference as the analog outputs. For calibration purposes, the input signal can be
switched to GND, to the reference voltage, or to the corresponding analog output (AO1 to AI1, AO2 to AI2, …,
AO8 to AI8) for all inputs simultaneously. The electronic switch is controlled by software.
AI 1
-8
AO 1-8
FAST AO
Fuses
AC input
PE
PE
Li
ne filt
er
Power
switch
+5V
DGND
-5V
+15V
AGND
-15V
+15V
AUX GND
-15V
Lin
e
voltage
detection
GND BNC
connector
AUX PS
connector
DEVICE SC 01/02/03
connector
±15V auxiliary
power supply
±15V
power supply
±5V
power supply
Power LED
Linear power supply
100Ω 100Ω
LPF
LPFLPF
ADC
DAC
AGND
AGND
DAC
CPLD
Isolation
1kΩ
100n
FPGA DGND
FPGA +5V
Serial communication
PE
PE
PE
10kΩ
100n
Temp.
sensor
FAST AO
Vref
Stabilized
Vref
AGND
AGND
U B
AGND
10kΩ
1n
To Next Page
Loading...