UG-630 Datasheet, PDF (3/8 Pages) Analog Devices – Evaluation Board User

Evaluation Board User Guide
UG-630
EVALUATION BOARD CIRCUITRY
PCB EVALUATION GOALS
The EVAL-ADuM144xQSOP16-EBZ board is intended to
achieve the following goals:
• Evaluate the full range of iCoupler data transfer functions
• Power each side of the iCoupler isolator independently
• Allow high differential voltage to be applied between the
two sides of the iCoupler isolator
• Allow connecting easily to power and instrumentation
Although the evaluation board comes with the ADuM1441ARQZ
iCoupler digital isolator installed, the board is also compatible with
the ADuM1440ARQZ, ADuM1442ARQZ, ADuM1445ARQZ,
ADuM1446ARQZ, and ADuM1447ARQZ, and the user can sub-
stitute any of these components in place of the ADuM1441ARQZ.
CONNECTORS
The PCB provides support for three types of interconnections:
• SMA edge-mounted connectors
• Through-hole signal ground pairs
• Terminal blocks for power connections
With these three options, both temporary and permanent
connections to the board can easily be made.
When coaxial connections are desired, SMA connector positions
are available for VDD1A, VDD1B, VDD2A, and VDD2B power supplies,
as well as all digital inputs and outputs. These SMA connector
positions are left unpopulated so that the user can customize
the connectors for a given application. Figure 2 shows examples of
installed SMA connectors; these connectors were chosen because
they are not only low profile and provide excellent mechanical
connections to the PCB but also support 50 Ω coaxial cabling.
Because most lab equipment is compatible with BNC connectors,
adaptors may be required to use some on-board connectors.
1) SCOPE PROBE
Power can be connected through the P1 and P2 terminal blocks or
can be wired directly to the PCB via the P13 and P14 through-
hole connectors. Each through-hole pair provides a power ground
pair with the power on the Pin 1 hole. The pin spacing of each
through-hole connector is 200 mil between centers. This matches
the pin spacing required for Tektronix active scope probes. If a
scope probe connection is desired, the header shown in Figure 2
can be soldered into the through-hole positions, and the signal pin
can be trimmed to match the height requirements of a Tektronix
active scope probe.
POWER INPUT
Each side of the ADuM1440ARQZ/ADuM1441ARQZ/
ADuM1442ARQZ/ADuM1445ARQZ/ADuM1446ARQZ/
ADuM1447ARQZ iCoupler isolator requires an off-board power
source. Each power source must be independent if common-mode
voltages are to be applied across the isolation barrier. Sharing a
single supply for both sides of the part across the isolation barrier
does not harm the isolator, and it is useful for functional testing
of the ADuM1440ARQZ/ADuM1441ARQZ/ADuM1442ARQZ/
ADuM1445ARQZ/ADuM1446ARQZ/ADuM1447ARQZ iCoupler
isolator when common-mode voltages are not present. If common-
mode voltages are to be applied across the isolation barrier,
independent power supplies must be provided for each side of
the isolator.
A ground plane and a power plane are present on Layer 2 and
Layer 3 of the PCB on each side of the isolation barrier. Power
connects to VDD1A and VDD1B for Side 1 and connects to VDD2A
and VDD2B for Side 2. The A and B power pins on each side
cannot be powered separately.
DATA I/O STRUCTURES
Each data channel has a variety of structures to help configure,
load, and monitor both the input and output. Figure 3 shows one
of the datapaths from an external connection to the DUT pin.
Each channel has similar connections.
Starting at the external connection, the signal path is
2) SMA CONNECTOR
5) SCOPE PROBE
HEADER
3) TERMINAL
BLOCK
6) PADS TO
CONNECT SMA
4) SHORTING
JUMPER
Figure 2. Optional Components
1. A pad layout for a PCB board edge-mounted SMA
connector.
2. Two 0805 pads are provided where 100 Ω resistors to
ground can be installed. The combined resistance is 50 Ω
to provide a termination for a standard coaxial cable.
3. A standard 0805 pad layout that allows the coaxial and
termination structures to be connected to the rest of the
signal path.
4. A 0603 pad layout between the signal path and VDDxA or
VDDxB can be used for installing a pull-up resistor.
5. A populated 2-pin header provides a signal ground pair
that can be used for clip leads or for shorting a channel to
ground temporarily.
6. There are groupings of three open through holes, consisting
of a signal and two ground connections. These holes can be
used for hardwiring signal wires into the PCB, installing a
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