| 摘要 |
Apparatus 30 for processing signals, arranged on an integrated circuit 20, comprises an analogue input port InpA1/InmA1 that receives an input signal, and a detector fig.3:32 that detects an operational state of the apparatus based on the input signal. The detector provides a digital control/enable signal 41/42, dependent on the operational state of the apparatus 30, to another apparatus 40 within the IC. In an embodiment, the analogue input port A1 may be connected to an RF signal source (fig.3a), in order that the IC should receive and process this signal. When this is not required, the analogue input port may be connected to ground, (fig.3b), or to Vdd, fig.3c. The resulting DC condition at the input, corresponding to a non-operational state of the circuit 11, is detected by DC detector 52. The DC detector then provides control signals which may enable another circuit, e.g. circuit 21 in block 40, which may then receive another signal. Thus, unused analogue inputs of an IC are combined with digital control of the IC and it is possible to use fewer pins, allowing smaller IC packages. |
