公开(公告)号：ITUB20156907A1

公开(公告)日：2017-06-07

申请号：ITUB20156907

申请日：2015-12-07

Applicant: ST MICROELECTRONICS SRL

Inventor： BOTTI EDOARDO ,  RAIMONDI MARCO

IPC: H03F3/217 ,  H03F1/32 ,  H03F1/52

公开(公告)号：ITUB20155835A1

公开(公告)日：2017-05-24

申请号：ITUB20155835

申请日：2015-11-24

Applicant: ST MICROELECTRONICS SRL

Inventor： BOTTI EDOARDO ,  RAIMONDI MARCO

IPC: G01R27/02 ,  H04R5/04

Abstract: A diagnostic circuit (40) for detecting the load status of an audio amplifier (20) is described. The audio amplifier (20) comprising two output terminals for connection to at least one speaker (30). In particular, the diagnostic circuit (40) comprises a first (402), a second (404) and (406) third circuit. The first circuit (402) is configured to generate a first signal (TV) indicating whether a signal (AAS) provided via the two output terminals comprises an audio signal. The second circuit (404) is configured to detect a first measurement signal being indicative for the output current ( I out ) provided via the two output terminals, and compare the first measurement signal with at least one threshold in order to generate a second signal (LS) indicating whether the output current ( I out ) has a low current amplitude profile or a high current amplitude profile. The third circuit (406) is configured to generate a diagnostic signal (DIAG) as a function of the first (TV) and the second (LS) signal. For example, the diagnostic signal (DIAG) may indicate an open load condition when the first signal (TV) indicates that the signal (AAS) provided via the two output terminals comprises an audio signal and the second signal (LS) indicates a low current amplitude profile.