CX20787 Datasheet, PDF (1/8 Pages) Conexant Systems, Inc – Cap-less Stereo class G

CX20787
Ultra Low-Power I²S Audio Codec with Integrated Digital Signal
Processing Features^NEW
Features
‹ Cap-less Stereo class G
Headphone driver
‹ Two Stereo Differential 10 kΩ Line
(or Single Ended)
‹ Stereo Differential Speaker -
Class D Amplifier 2 Wrms 4Ω @
5 V.0 or 1 Wrms 4 Ω @3.2 V
‹ No pops, clicks, or zipper noise
during any change of state
‹ Single-ended External Mono Mic
(Headset Jack)
‹ Three Differential Mic / Line -
shared with digital mic ports
‹ 2 Mic Bias
‹ Nokia / Apple headset type
detection & mic/Gnd switch
control
‹ Inline command sensing
‹ Stereo 24-b ADCs, & 1 digital
ADC
‹ Stereo 24-b DACs
‹ HW Audio Signal Processing
– 5-band bi-quad EQ on stereo
output
– 2-knee stereo DRC
‹ Digital Mic support, clk support:
1.5,3 MHz,
‹ Two 4-wire bi-directional I²S/PCM,
1 Aux (pass-thru)
‹ SPI (5 MHz)/I²C (100/400 kHz)
‹ 4 GPIO
‹ Writer Sequencer to minimize
setup
‹ MCLK clock input (10-48 MHz) for
reference to 2 PLLs
‹ 1.8 V +/- 0.5 V, 3.3 V
‹ 4x3.9x1mm 72-p WLCSP, 0.4mm
ball pitch
‹ -40 to +85 deg C ambient, -40 to
+125 C junction
Applications
‹ Smartphones
‹ Tablets
‹ Ultrabooks
‹ Portable Media Player
Overview
The CX20787 is an ultra low-power, I²S stereo audio codec with integrated Class-D
speaker amplifiers and power-efficient Class G headphone amplifiers with in- line
DSP features. Combined with our software driver and design support, this is an ideal
turnkey solution for Tablets, Ultrabooks, Smartphones etc.
The device features a pair of ProCousticTM headphone drivers. The high-
performance headphone drivers eliminate the need for an external headphone
amplifier and DC blocking capacitors. The capless architecture outputs a full-range
frequency response at 97 dB dynamic range. CX20787 supports both Apple and
Nokia style headset jacks with fully integrated auto detect and switch and inline
command button sensing. All output ports feature PopShield circuitry that eliminates
pops or clicks.
The integrated stereo filter-less Class-D amplifier with Spread Spectrum EMI
dispersion technology is capable of outputting 2W-rms into a 4 Ω speaker with 5 V
supply rail. The device can be completely powered by a 3.3 V supply rail with
reduced Class-D output power. All other internal supply rails are generated by the
integrated LDOs.
The digital I/Os, such as I²S ports, Conexant Audio Bus, etc., support a wide range
of topologies for connections to both the application processor and baseband
processor simultaneously. Additional salient features of CX20787 include Write
Sequencer for ease of use.
CX20787 features Hardware Digital Volume Control, similar to an infinite volume
control knob commonly found in high-end AV equipment. There is also a single-bit
stream digital microphone interface that connects up to 3 digital microphones for
dual microphone array implementations. The Digital Microphone Interface (DMI) is
optimized with a hardware DC-level filter, which compliments and improves the
compatibility with more digital microphones. A fully configurable hardware EQ and
dual knee Dynamic Range Control with reconfigurable inputs is integrated to improve
frequency response, maximize output volume, and protect speakers from over
driving.
Functional Block Diagram
Digital
Microphone
3 Diff/SE
Microphone/
Line Inputs
3 x I²S Interfaces
Gain/Mute
Mixer/MUX
PGA
ADC
ADC
ADC
PLL
DAC
Speaker
EQ/DRC
DAC
I²C/SPI Bus
GPIOs and
Jack Sense
Mixer
Outputs
Capless Class-G
Headphone/Headset
2 Diff/SE
Line Outputs
2W RMS
Stereo Speaker
(Class-D)