Applications Information

MC13192 Technical Data, Rev. 3.2

22

Freescale Semiconductor

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If the MCU is also going to be used in low power modes, be sure that all unused IO are programmed

properly for low power operation (typically best case is as outputs in the low state). The MC13192

is commonly used with the Freescale MC9S08GT/GB 8-bit devices. For these MCUs:

— Use only STOP2 and STOP3 modes (not STOP1) with these devices where the GPIO states are

retained. The MCU must retain control of the MC13192 IO during low power operation.

— As stated above all unused GPIO should be programmed as outputs low for lowest power and

no floating inputs.

— MC9S08GT devices have IO signals that are not pinned-out on the package. These signals must

also be initialized (even though they cannot be used) to prevent floating inputs.