This new approach will impact the system architecture of applications using small TECs including those where cooling is omitted for reasons of system cost and power dissipation. Applications include cooling of lower power laser diodes and other active or passive devices in the telecommunications, photonics, optoelectronics, and sensors markets.
Micropelt’s MPC-D403/404 TECs are fabricated using semiconductor manufacturing processes that enable Micropelt to produce the small micro-coolers. Feature sizes of 45 microns can accommodate 50 thermocouples per square millimeter, about 10 times more than bulk Peltier technology can offer.
“Our micro-structuring technology is able to scale to application specific dimensions, electrical requirements, and thermal properties,” explains Joachim Nurnus, chief technology officer of Micropelt. “We measure drive currents 10 times smaller than those known for similar bulk TECs whose few thermocouples create an electrical resistance much below 1 Ohm and hence a drive current well above 1 ampere.”
The MPC-D40x series can pump over 600 milliWatts with a drive current of 200 milliamps as required for thermal management of low power edge emitting lasers or VCSELs. At low drive currents the power efficiency of the TEC increases. At the same time, the design of the control circuitry can be simpler, which also translates to reductions on the bill-of-materials and circuit board footprint.
“Everyone wants their transceiver modules to be smaller and more energy efficient,” says Wladimir Punt, vice president of sales and marketing for Micropelt. “We analyzed the thermoelectric system architecture and concluded that for very small TECs the drive current is key to solving the prevailing power consumption and heat dissipation issues. Cutting the drive current by 90% can improve the overall cooling system efficiency by 50%, because the drive voltage remains at a level where buck regulators can provide good efficiencies. This will help photonic packaging and system designers to develop components consuming less energy, producing less heat, and fitting into smaller packages.”
Micropelt’s wafer-based production technology brings economies-of-scale to the high volume manufacture of TECs. The TEC control system not only benefits from standard, inexpensive, readily available, and ultra-small TEC control circuit components, but its overall power efficiency results in reduced power consumption and heat dissipation on densely packed line cards. Micropelt’s micro-cooler represents a compelling technology for use with products not normally exposed to active cooling, but that would benefit from higher performance, tighter specifications, and further miniaturization.
