Si 8 7 x x - EV B
Si87
XX
LE D E
MULATOR
I
NPUT
I
S OLATOR
E
VALUATION
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1. Introduction
The Si87xx evaluation board allows designers to evaluate Silicon Lab's family of CMOS based LED Emulator Input
isolators. The Si87xx isolators are pin-compatible, single-channel, drop-in replacements for popular optocouplers
with data rates up to 15 Mbps. These devices isolate high-speed signals and offer performance, reliability, and
flexibility advantages not available with optocoupler solutions. The Si87xx series is based on Silicon Labs'
proprietary CMOS isolation technology for low-power and high-speed operation and are resistant to the wear-out
effects found in optocouplers that degrade performance with increasing temperature, forward current, and device
age. As a result, the Si87xx series offer longer service life and dramatically higher reliability compared to
optocouplers. Ordering options for the family include open collector output with or without integrated pull-up
resistor or with an output enable pin. The evaluation kit consists of four separately orderable boards with each
board featuring either the DIP8, SOIC8, SDIP6, or LGA8 package. For more information on configuring the isolator
itself, see the Si87xx product data sheet and as well as application note “AN681: Using the Si87xx LED Emulator
Input Family of Isolators”.
1.1. Kit Contents
The Si87xx Evaluation Kit contains the following items:
Si87xx
based evaluation board as shown in Figures 1 through 4.
Si87xx LED Emulator Input isolator (installed on the evaluation board)
Si8710
(DIP8, SDIP6)
Si8712 (SOIC8, LGA8)
Figure 1. Si87xx DIP8 Evaluation Board Overview
Figure 2. Si87xx SOIC8 Evaluation Board Overview
Rev. 0.3 9/12
Copyright © 2012 by Silicon Laboratories
Si87xx-EVB
Si87xx-EVB
Figure 3. Si87xx SDIP6 Evaluation Board Overview
Figure 4. Si87xx LGA8 Evaluation Board Overview
2
Rev. 0.3
Si87xx-EVB
2. Required Equipment
The following equipment is required to demonstrate the evaluation board:
1
digital multimeter
2 multimeter test leads (red and black)
1 oscilloscope (Tektronix TDS 2024B or equivalent)
1 BNC splitter
3 coaxial cables
1 dc power supply (HP6024A, 30 V dc, 0–100 mA or equivalent)
2 BNC to clip converters (red and black)
2 Banana to clip wires (red and black)
1 Clip to Clip wire (any color)
1 function generator (Agilent 33220A, 20 MHz or equivalent)
Si87xx Evaluation Board (board under test)
Si87xx LED Emulator Input Evaluation Board User's Guide (this document)
Rev. 0.3
3
Si87xx-EVB
3. Hardware Overview and Demo
Figure 5 illustrates the connection diagram to demonstrate the Si87xx-DIP8 EVB. The other footprint boards
demonstrate in a similar fashion. This demo transmits a 500 kHz (5 V peak, 50 percent duty cycle) square wave
through the isolator to its output (Vo). In this example, VDD is powered by a 5 V supply. Figure 6 shows a scope
shot of CH1 (input) and CH2 (output). Note that if a user wants to evaluate an LED Emulator Input isolator other
than the ones pre-populated, this can be accomplished by removing the installed device and replacing it with the
desired footprint-compatible isolator device.
Input
to Scope
CH1
Output
to Scope
CH2
+
Signal Input
(500 kHz, 5 Vpk)
Square Wave
+
_
+
_
-
Power Supply
(5 V)
Figure 5. Summary Diagram and Test Setup
Figure 6. Oscilloscope Display of Input and Output
4
Rev. 0.3
Si87xx-EVB
3.1. Board Jumper Settings
To run the demo, follow the instructions below. Review Figure 5 and Figures 11 through 14 if necessary.
1. If demonstrating the SOIC8 or LGA8 EVB featuring the Si8712 (Si8710 for DIP8), ensure that J2, J4, and
J5 are installed as shown in Figure 1, 2, or 4.
2. If demonstrating the SDIP6 EVB featuring the Si8710, ensure that J2 and J3 are installed as shown in
Figure 3.
3.2. DC Supply Configuration
1. Turn OFF the dc power supply and ensure that the output voltage is set to its lowest output voltage.
2. Connect the banana ends of the black and red banana to clip terminated wires to the outputs of the dc
supply.
3. Then, connect the clip end of the red and black banana to clip wires to P2. The red wire goes to Pin1. The
black wire goes to Pin4.
4. Turn ON the dc power supply.
5. Adjust the dc power supply to provide 5 V on its output.
6. Ensure that the current draw is less than 25 mA. If it is larger, this indicates that either the board or Si87xx
has been damaged or the supply is connected backwards.
3.3. Wave Form Generator
1. Turn ON the arbitrary waveform generator with the output disengaged.
2. Adjust its output to provide a 500 kHz, 0 to 5 V peak square wave (50 percent duty cycle) to its output.
3. Split the output of the generator with a BNC splitter.
4. From the BNC splitter, connect a coaxial cable to CH1 of the scope. This will be the input.
5. Connect a second coaxial cable to the BNC splitter, and connect a BNC-to-clip converter to the end of the
coaxial cable.
6. From here, connect the clip end of the BNC-to-clip converter to P1, Pin1 (red wire here) and Pin3 (black
wire here). The positive terminal is Pin1 on P1.
7. Connect one end of a third coaxial cable to a BNC-to-clip converter (note that a scope probe can be used
here instead).
8. From here, connect the clip end of the BNC-to-clip converter to P2, Pin3 (red wire here) and Pin4 (black
wire here). Vo is on P2 Pin3.
9. Connect the other end of the coaxial cable to CH2 of the oscilloscope. This will be the output.
10. Engage the output of the waveform generator.
3.4. Oscilloscope Setup
1. Turn ON the oscilloscope.
2. Set the scope to Trigger on CH1 and adjust the trigger level to 1 V minimum.
3. Set CH1and CH2 to 2 V per division.
4. Adjust the seconds/division setting to 250 ns/division.
5. Adjust the level indicator for all channels to properly view each channel as shown in Figure 6.
A 500 kHz square wave should display on Channel 1 of the scope for the input and an inverted 5 V version of this
square wave should display the output on Channel 2, as shown in Figure 6. This concludes the basic demo. For
more advanced demos, see the following sections.
Rev. 0.3
5