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Input/Output Cable
The EVM provides M5x0.8 stud for external connections. Two M5 jam nuts are included. The
maximum input current for parallel EVM can go over 200A, user must choose proper input cable size.
The output voltage of the parallel EVM can range from 0.5V to 2V, and is capable of delivering up to
720A. Cable voltage drop must be controlled in this application. For continuous 360A and above
operation, ABB recommends user to develop proper bus bar to distribute currents. Multiple DC load
in parallel is a must for sinking 720A. In general, output connection should be kept as short as
possible by means of reducing voltage drop on each cable. Cable length/size should be the same in
order to evenly distribute current. Avoid scratching the surface of the PCB when fasten the cable
assemblies, exposed PCB can potentially create damage.
Input/Output Measurement
To measure Input/Output voltage properly, SMA connectors are recommended to be populated at
M_VIN and M_VOUT.
Ideally oscilloscope should use 50Ω input impedance for measuring output
voltage ripple, or use a
50Ω attenuator in series with 1MΩ input impedanc
e. Set the oscilloscope to
5mV/div or below to examine ultra-low ripple performance of DJT090s in parallel. M_VOUT is very
sensitive to ground loop noise, thus while measuring the output voltage ripple, the oscilloscope
should be floating and can only be connect to M_Vout
. Don’t connect
the rest of oscilloscope
channels.
On-Board Pulse Load
To use on-board pulse load, SMA connectors are recommended to be populated at IN_IREF and
ICHECK1.
Input/Output Capacitor
The parallel EVM comes with limited amount of input and output capacitors. Although the amount
of capacitors is sufficient to evaluate the basic performance, user needs to decide whether to
change/add more capacitors to unleash superior performance of DJT090. For output impedance
matching purposes, all channel should equip equal amount of capacitors. POSCAP is recommended.
Each channel contains following amount of capacitors,
•
Input capacitor: 2x470uF (Aluminum Polymer) + 8x22uF (Ceramic)
•
Output capacitor: 4x680uF (Tantalum Polymer) + 12x47uF (Ceramic)
Address Resistor
By default, the PMBus address resistors are pre-installed, see below diagram to see the addresses
associated to each channel (RX01 and RX02, X refer to channel index). Any need to change the
address must be done prior powering up the EVM. For PMBus address resistor selection, please refer
to DJT090A0X43-SRPZ datasheet. Each paralleled channel must have a unique address.
