TF5134N Datasheet, PDF (3/4 Pages) MORNSUN Science& Technology Ltd. – Isolated Transmitter

Isolated Transmitter
TFxxxxN Series
Design Reference
1. Typical application
1) Schematic diagram
Power In
Signal In
Power In
OSC
AMP
MOD
ISO Power
ISO Power Out
DEMOD AMP
Signal Out
Gain Tri m
Off set Trim
Fig. 1
2) Typical application——Isolation application of AO board card in DCS system
Application circuit for typical multi-channel signal acquisition is as below:
TF_ N output module
Sout1
DAC
isolation bus interface
485
isolation transceiver
Sout2
Sout3
Sou t4
DAC
DAC
DAC
I/O Bus _MCU
CAN isolation transceiver
Sin
Ethe rnet network
transformer
Fig. 2 Isolation application figure of AO board card in DCS system
Function
In the figure 2, Sin are input signals for peripheral circuit. The input signals can be sent to MCU and isolated with Sin by 485 isolation
transceiver, CAN isolation transceiver and Etherent network transformer, MCU control system receive the signals, and output digital signals
after signal processing. DAC is digital to analog converter, digital signals can be transferred to analog signals by DAC . TF_N output module
isolation output the analog signals transferred from DAC. Sout1, Sout2, Sout3 and Sout4 are multiplex output isolation signals.
Working principle
When the circuit works, peripheral circuit provides input signals Sin, and it transfers input signals to MCU control system by isolated bus
interface. The MCU receives the signals and manage them, then output digital signals)The digital signals are transferred by I/O bus. Digital
signals are converted to analog signals through DAC. After these analog signals get through TF_N output module, we can get isolation
signals. The whole working process realizes that the inner signals of control system are isolated with the peripheral circuit ) and the output
signals,Sout1,Sout2,Sout3 and Sout4 are isolated and not interfere with each other)
3) Application——Zero and full adjustment function
Zero and full adjustment recommended setting circuit is as shown
10 +
Power input C1
D1
11 -
Singal input ^D4
Full adjustment
potent iomet er
9+
8-
-
7
+
6
18 +
D2
C2 _{Isolation power output}
17 -
-
16
Zero adju stment
+ potent iomet er
15
1+
D3
2-
Singal output
Fig. 3 Zero and full adjustment circuit
Function
Zero adjustment function by setting up adjustment resistor at the zero point can change the zero signal transmission, which makes the
output signal overall migration. Full adjustment function is also called the gain adjustment function, and it can change the ratio of signal
transmission through the set up corresponding adjust resistance at the full adjustment, and the isolation transmission proportion of input and
output signal value would be changed.
Usage
Adding and reducing negative zero resistance can reduce the zero of signal output. Adding and reducing positive zero resistance can
increase the zero of signal output. Adding and reducing negative full adjustable resistance can reduce the ratio of signal transmission,
Adding and reducing negative full adjustable resistance can increase the ratio of signal transmission. You can use potentiometer to adjust
the output signal of zero and full in practical application. As shown in the figure 3, the terminal of full or zero adjustment is connected to the
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