CRD-5376 Cirrus Logic Inc, CRD-5376 Datasheet - Page 17

• Manufacturer Part Number: CRD-5376
• Description: Audio Modules & Development Tools Ref Bd LP Mlt-Ch Decimation Filter
• Manufacturer: Cirrus Logic Inc

Specifications of CRD-5376

• Description/function: Audio D/A
• Operating Supply Voltage: 3.3 V
• Product: Audio Modules
• Supply Current: 300 mA
• For Use With/related Products: CS3301A, CS3302A, CS4373A, CS5371A, CS5372A, CS5376A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2.2.2.2
The analog outputs of the CS3301A/02A differential amplifiers are split into rough charge and fine charge
signals for input to the CS5372A ∆Σ modulators.
Analog signal traces out of the CS3301A/02A amplifiers and into the CS5372A modulators are 4-wire
INR+, INF+, INF-, INR- quad groups, and are routed with INF+ and INF- as a traditional differential pair
and INR+ and INR- as guard traces outside the respective INF+ and INF- traces.
2.2.2.3
The CS5372A ∆Σ modulators are 4th order and high frequency input signals can cause instability. Simple
single-pole anti-alias RC filters are required between the CS3301A/02A amplifier outputs and the
CS5372A modulator inputs to bandwidth limit analog signals into the modulator.
For the CRD5376, the CS3301A/02A amplifier outputs are connected to external 680 Ω series resistors,
and a differential anti-alias RC filter is created by connecting 20 nF of high linearity differential capacitance
(2x 10 nF C0G) between each half of the rough and fine signals.
2.2.3
Each CS5372A dual modulator performs the A/D function for differential analog signals from two
CS3301A/02A amplifiers. The digital outputs are oversampled ∆Σ bit streams.
2.2.3.1
The modulator analog inputs are separated into rough and fine signals, each of which has an anti-alias
RC filter to limit the signal bandwidth into the modulator inputs.
2.2.3.2
The CS5372A ∆Σ modulator requires differential offset to be enabled to eliminate idle tones for a termi-
nated input. The use of internal offset to eliminate idle tones is described in the CS5372A data sheet. By
default, OFST is enabled for the CS5372A modulators on CRD5376.
DS612RD2
Analog Signals
INR1, INF1
INR2, INF2
VREF
Digital Signals
MDATA[1..2]
MFLAG[1..2]
MCLK
MSYNC
PWDN[1..2]
OFST
Delta-Sigma Modulators
Rough-Fine Outputs - OUTR, OUTF
Anti-alias RC Filters
Rough-Fine Inputs - INR, INF
Offset Enable - OFST
Modulator delta-sigma data outputs
Modulator over-range flag outputs
Description
Channel 1 analog rough / fine inputs
Channel 2 analog rough / fine inputs
Voltage reference analog inputs
Description
Modulator clock input
Modulator synchronization input
Power down mode enable
Internal offset enable (+VD when using CS3301A/02A)
CRD5376
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