The MPC-D40x Series of thermoelectric coolers from Micropelt GmbH, Freiburg, Germany, provide an electrical resistance of >30 ohms on a single square millimeter footprint. The TEC, in combination with its controller system, can be driven at an efficiency of 90% and better. Fabricated using semiconductor manufacturing processes, the devices have 45 µm feature sizes for 50 thermocouples/mm2 and can pump >60 mW with a 200 mA drive current. At low drive currents the TEC's power efficiency increases. Applications include cooling of lower-power laser diodes and other active or passive devices in the telecommunications, photonics, optoelectronics, and sensors markets.