Philanthropist Alfred E Mann, an entrepreneur and inventor whose wide-ranging business endeavours included aerospace, pharmaceuticals, electronic circuitry and biomedical research, has died aged 90.

His death was announced by MannKind Corp, where Mr Mann served as chairman of the company based in Valencia, California, from 2001 to earlier this month.

The son of an immigrant grocer, Mr Mann amassed his fortune through founding a string of companies.

His pioneering work included development of the first rechargeable pacemaker and inhalable insulin.

He started out in aerospace, where his firms developed solar cells, semiconductors and other technologies for America's military and space programmes.

Later, he earned hundreds of millions of dollars by producing pacemakers for heart patients and insulin pumps to help treat diabetics.

In 2007, Forbes magazine estimated his fortune at 2.4 billion US dollars (£1.7 billion).

MannKind chief executive Matthew Pfeffer called Mr Mann an inspiration who will be missed by countless patients with diabetes and other serious illnesses whose lives were improved by Mr Mann's work.

"Our resolve is now stronger than ever to continue Al's legacy of medical innovation," Mr Pfeffer said in a statement.