基于CS35L00設(shè)計(jì)的2.7W x 4高效D類音頻放大技術(shù)

CS35L00是Cirrus公司的2.7W高效單聲道D類音頻放大器，采用無濾波器混合型D類架構(gòu)，靜態(tài)電流小于1mA，10% THD+N時能向4歐姆提供2.7W功率，A加權(quán)SNR為-98dB，主要用于手機(jī)，上網(wǎng)本，PND，有源揚(yáng)聲器和手提游戲機(jī)。本文介紹了CS35L00主要特性，方框圖，SD和FSD模式以及HD和FHD模式的典型連接框圖，CDB35L00-X4 放大器演示板主要特性，電路圖和材料清單（BOM）。

The CS35L00 is a 2.7 W high efficiency Hybrid Class-D audio amplifier with low idle current consumption and a selectable gain.

The CS35L00 features an advanced closed-loop architecture to provide 0.02% THD+N at 1 W and -75 dB PSRR at 217 Hz.

A flexible Hybrid Class-D output stage offers four modes of operation: Standard Class-D (SD) mode offers full audio bandwidth and high audio performance; Hybrid Class-D (HD) mode offers a substantial reduction in idle power consumption with an integrated Class-H controller; Reduced Frequency Class-D (FSD) mode reduces the output switching frequency, producing lower electromagnetic interference (EMI); and Reduced Frequency Hybrid Class-D (FHD) mode produces both the lower idle power consumption of HD mode and the reduced EMI benefits of FSD mode.

Requiring minimal external components and PCB space, the CS35L00 is available in a 3.0 mm x 3.0 mm, 10-pin DFN package in Commercial grade (-10℃ to +70℃).

CS35L00主要特性：

Filterless Hybrid Class-D Architecture

– 1 mA Quiescent Current

– 1 x 2.7 W into 4 ohm (10% THD+N)

– 1 x 2.1 W into 4ohm (1% THD+N)

– 1 x 1.6 W into 8 ohm (10% THD+N)

– 1 x 1.3 W into 8 ohm (1% THD+N)
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Advanced Delta-Sigma ?Closed-loop Modulation

– 98 dB Signal-to-Noise Ratio (A-Weighted)

– 0.02% THD+N @ 1 W (SD HD Mode)?

Integrated Protection and Automatic Recovery for Output Short-circuit and Thermal Overload

Pin-compatible 9-ball WLCSP family for easy upgrade path

– CS35L01: +6 dB default Gain

CS35L03: +12 dB default Gain

Pop and Click Suppression

CS35L00主要應(yīng)用：

Mobile Phones

Laptops/Netbooks

Portable Navigation Devices

Active Speakers

Portable Gaming

圖1。CS35L00方框圖

圖2。CS35L00 SD和FSD模式典型連接框圖

圖3。CS35L00 HD和FHD模式典型連接框圖

Note:3. The value of the capacitance connected to the LFILT+ net should not exceed 4.7uF. Presence of a capacitance above 4.7uF will prevent proper HD and FHD operation.

2.7 W x 4 CS35L00 放大器演示板

The CDB35L00-X4 demonstrates the CS35L00 high-efficiency Hybrid Class-D audio amplifier. This demonstration board implements a four-channel, quad amplifier system that delivers 2.7 W per full-bridge channel into 4-ohm loads using a single +5 V supply.Differential audio inputs can easily be connected through the J10, J20, J30, and J40 headers. If desired, the gain can be adjusted through the optional input resistors.Component landings are available for an optional EMI output filter.

The CDB35L00-X4 can be configured to evaluate the four operational modes and two gain settings of the CS35L00 amplifier. Mode, Gain, and Shutdown control is available through the S1 switch. Hybrid control is vailable through the R13, R23, R33, and R43 resistors.

圖4。2.7 W x 4 CS35L00 放大器演示板外形圖

主要特性：

Contains 4 CS35L00 Hybrid Class-D Amplifiers

Selectable +6 dB or +12 dB Gain

Selectable Operational Modes

Device Shutdown Control

Delivers 2.7 W/Ch into 4ohm at 10 % THD+N

Delivers 1.6 W/Ch into 8 ohm at 10 % THD+N

Differential Mono Analog Inputs for each CS35L00 Amplifier

Demonstrates Recommended 4-Layer Layout and Grounding Arrangements

– Optional Output Filter Connections

– Optional Gain Adjustment Resistors

Powered by Single +2.5-5.5 V Power Supply


圖5。CDB35L00-X4 放大器演示板框圖

圖6。CDB35L00-X4 放大器演示板電路圖
CDB35L00-X4 放大器演示板材料清單（BOM）：