GW Instek GDM-8245 - Block Diagram

Block Diagram
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BLOCK DIAGRAM
Block Diagram
Description
The block diagram below shows the GDM-8245 system block
diagram. The system block can be divided into 3 main parts:
power supply circuitry, digital control circuitry and analog
signal processing circuitry. A detailed summary of each section
follows.
±15V (U102, U105)
±3.1V (Q101, Q102)
+1.8V x2 (U101,
U104)
Power Supply Unit
Front Panel Button
Inputs U603, U202
Main
Controller
U202
W78E054C
U301 FS9704B DMM front-end Chip
Input Signal
Conditioning Network
K301~304
A/D Converter
Ohm’s Current
Source
True RMS to DC
Converter U401
U201 2048 bits
EEPROM for
calibration memory
Range Routers
External AC
Amplifier
U403
CLK Oscillator
U207, X201
Function
Selector
U206 Processor
Supervisory Circuit
Microprocessor & Logic Interface
Front Panel LED
Display Drivers U602,
U603, U604
Current Shunts
R301~303, 305, 308
& Shunt Selectors
K307~310
6.2Vref (D316) & A/D
Ref. (R310, R311)
Function Switching
Controller U203,
U204
Front Panel Data
Bus Driver U205