Approach radically alters design and manufacture of large electronic systems
By Dan Strassberg -- EDN, March 4, 2004
Power-One’s latest products can significantly influence the design and manufacture of large electronic systems for such purposes as telecommunications central-office equipment, high-performance computing, and automatic-test equipment. The reason is the company’s system-oriented approach to the design of its newest modules: the Z7100 PDM (power digital manager), which costs less than $15 in evaluation quantities, and the ZY7020 and -7120 POL (point-of-load) dc/dc converters, which cost less than $20 each in similar quantities.
The ZY7020 mounts with its pc substrate parallel to the plane of the host board, whereas the single-in-line ZY7120 mounts with its substrate normal to the board. Both of the 1.25×0.3×0.55-in. POL modules operate from an unregulated dc voltage in the unusually wide range of 3 to 13.2V and deliver a programmable regulated dc output of 0.5 to 5.5V at 20A maximum. All of the modules can communicate over an I2C bus. One Z7100 manages as many as 32 POL devices, which needn’t be of Power-One manufacture (Picture).
By designing its POL units to operate from input voltages in a 4.4-to-1 range, Power-One has removed constraints from the host board’s unregulated IB (intermediate-bus) voltage. The POL devices work with all of the popular IB values: 5, 8, or 12V nominal. Thus, if you use different IB voltages on different boards, you need not stock different POL devices. Even more important is the wide-range 11-to-1 programmability of the POL devices’ regulated output voltages. As IC supply voltages have proliferated, the need to stock different POL units for each voltage has created an inventory-management nightmare for system manufacturers. Just one type of Power-One programmable POL unit covers the entire range of supply voltages that modern digital ICs use, although the company plans to add lower cost POL units whose maximum output current is less than the initial units’ 20A.
The POL devices internally store application-specific operating parameters. Thus, simple applications require no PDM. In addition, you can use a resistor to program a POL unit’s output voltage. Also, the PDM need not operate during system start-up, so there is no Catch 22; systems in which a POL unit supplies power to a PDM start normally.
The PDM provides a more complete set of control and monitoring functions than do standard power-management ICs. Moreover, unlike most such ICs, the PDM requires no external components, such as FETs in series with POL outputs to create tracking supplies.
For configuring, troubleshooting, and failure analysis, Power-One provides ZIOS (Z-Series Intelligent Operating System), a graphical application that enables you to program all of the many customization parameters, such as start delay and ramp-up speed, which the POL units can store.
Power-One, 1-805-987-8741, www.powerone.com.
