Abstract: A package (10, 110, 210, 310) comprises a planar heat exchanger (14, 114, 314) with an air inlet (16, 116, 316) and an air outlet (18, 118, 318) thermally coupled to an electronic module (12). A flexible diaphragm operated pump (20, 120, 220, 320) with one-way valves (132, 134; 232, 234; 332, 334) are disposed between the air inlet and the air outlet. The diaphragm is oscillable to pump air through the heat exchanger from the inlet and out through the outlet. One or more piezo-electric transducers (138, 138; 232, 238; 338) are mounted on a diaphragm (136, 236, 336) and a power source and oscillator (140) are coupled to the transducer(s) to cause the diaphragm to rapidly flex and pump the air. The heat exchanger includes an internal structure (142, 342) defining a multitude of continuous air conducting passages.