Tektronix AFG31000 Series Service Manual

Theory of operation
AFG31000 Series Arbitrary Function Generator Service Manual
25
Generator section
This section provides information on the components that ensure the functionality and performance of
the AFG31000 Series instruments.
Instrument area Description
Isolator
Transmits the serial control signal from the CPU board to the following
circuits with electrical insulation.
Clock circuit
Generates a 2 GHz high-speed clock necessary for the signal
generation from a 10 MHz reference clock by PLL. This circuit has a
function of selecting the reference signal source as well.
FPGA
The field-programmable gate array (FPGA) is the key IC to achieve
Direct Digital Synthesis, waveform SRAM 128 K, x8 MUX, Modulation,
Burst and Sweep. The FPGA manages most of the generator section.
DDR
Three pieces
* 16 bits width
* 128 M depth for each channel
Stores user-defined waveform data in advance mode.
DAC
14-bit 2.5 GSPS update rate digital to analog converter. Receives
digital signal from FPGA and generate corresponding analog signal.
Trigger circuit
Receives an External Trigger input signal, executes the level
conversion, then supplies the level converted trigger signal to the
FPGA.
Pre-amplifier
circuit
Converts the differential output signal of the DAC to single ended
output, then supplies the single ended output to the Output Amplifier
through the Attenuator.
Output amplifier
The output of the pre-amplifier is amplified and output. A low-pass filter
(LPF) is used when a sine wave is output.
Trigger out
The Sync Out signal from the FPGA is level converted to Trigger Out.
ADC
Modulation by an external source is performed by digitally sampling the
external input from the Ext Modulation Input connector.
Local regulator
Supplies the necessary ±15 V, ±5 V,1 V, 1.5 V, 1.8 V, 3.3 V power.
On/Off relay
On or Off of the output signal.
Calibration circuit
DC Calibration of the output signal is done by a 24-bit AD Converter.
Output amplifier
The output of the pre-amplifier is amplified and output. LPF is used
when a sine wave is output.
Output filter
LPF is used when a sine wave is output.
InstaView circuit
Tek026 as the key part of InstaView circuit to provide the waveform of
the DUT input.

Tektronix AFG31000 Series Specifications

General

Brand	Tektronix
Model	AFG31000 Series
Category	Inverter
Language	English