ISD94100 Series Technical Reference Manual
Sep 9, 2019
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6.21 Audio DPWM Modulator (DPWM)
6.21.1 Overview
The DPWM modulator is sigma-delta modulator which is for class D amplifer. ISD94100 series has
3 DPWM modulator and each one can provide 2 differential pins.
6.21.2 Features
Differential Audio PWM Output (DPWM)
Support left channel,right channel and sub-woofer channel.
Support sample rates from 16~96kHz.
Programeable biquad filter with 10 band
PDMA data channel for streaming of PCM audio data.
Support the single precision floating point for input data and BIQ coefficient
Provides one 32-level FIFO data buffers for transmitting.
6.21.3 Block Diagram
APB
AFIFO
FltToFix
BIQ
6band
Spliter
BIQ 4band
SEL
2.0
2.0
2.0
2.0
2.0
2.0
2.1
2.0/2.1
DPWM_LP/DPWM_LN pin
DPWM_RP/DPWM_RN pin
DPWM_SP/DPWM_SN pin
Programmable Coefficient
Programmable Coefficient
DPWM
Modulator
Figure 6.21-1 DPWM Block Diagram
6.21.4 Basic Configuration
Clock source configuration
–
The source of DPWM peripheral clock is selected by DPWMSEL
(CLK_CLKSEL2[13:12]).
–
The DPWM peripheral clock is enabled by DPWMCKEN (CLK_APBCLK1[6]).
Reset configuration
–
The DPWM module is reset by DPWMRST (SYS_IPRST2[6]).
Pin configuration
Group
Pin Name
GPIO
MFP
DPWM
DPWM_LN
PA.4
MFP3
PC.12
MFP3