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Revision 1.10
46 - 86
AS3542 3v2
Data Sheet, Strictly Confidential - D e ta i l e d D e s c r i p t i o n - S Y S T E M F u n c t i o n s
STATUS CHANGE
The IRQ gets active when the source-state changes. The change bit and the status can be read to notice which inter-
rupt was the source. The IRQ stays active until the corresponding interrupt register gets read.
10.4.3 De-bouncer
There is a de-bounce function implemented for USB and CHARGER. Since these 2 signals can be unstable for the
phase of plug-in or unplug, a de-bounce time of 512ms/256ms/128ms/8ms can be selected by 2 bits in the
IRQ_ENRD_4 register (27h).
10.4.4 Interrupt Sources
25 IRQ events will activate the XIRQ pin:
Headphone connected
Headphone over-current
Microphone connected
Microphone remote control
Voice activation threshold reached
10bit ADC end of conversion
I²S changed (active/inactive)
USB changed (connect/disconnect)
Charger changed (end of charge or connect/disconnect)
Battery temperature high (at 45ºC or 55ºC with 100k
Ω
NTC)
Junction temperature high
RTC watchdog (e.g. after battery was changed)
Battery low (Brown-out voltage reached)
Wake-up from hibernation
Power-up key (pin PWRUP) pressed
Power rail monitor: over-voltage PVDD1, PVDD2, CVDD1, CVDD2, DCDC15
Power rail monitor: under-voltage PVDD1, PVDD2, CVDD1, CVDD2, AVDD27
10.4.5 Register Description
Table 34. Interrupt Related Register
Name
Base
Offset
Description
2-wire serial
1A-3h
Control of XIRQ signal, polarity and drive
2-wire serial
1Ch
Enables writings to extended register 1Ah-3 and 1Ah-5
2-wire serial
23h
Enable/disable PMU interrupts
2-wire serial
24h
Enable/disable wake-up, voice and PMU interrupts
2-wire serial
25h
Enable/disable charger, USB and supervisor interrupts
2-wire serial
26h
Enable/disable junction temperature, headphone, microphone
and I2S interrupt
2-wire serial
27h
Enable/disable PMU, RTC, ADC10 and microphone interrupt,
set VBUS and CHGIN debounce time