NCP2821FCT1G

Overview

The NCP2821FCT1G is a mono Class-D audio power amplifier by onsemi, designed for portable communication devices. It delivers up to 2.65 W continuous average power into a 4 Ω BTL load from a 5.0 V supply, and 500 mW into an 8 Ω BTL load at 3.0 V with less than 1% THD+N. The device operates on a single supply voltage ranging from 2.5 V to 5.5 V. Key electrical parameters include a typical efficiency of 90%, a switching frequency of 250 kHz, and a shutdown current of 1.5 µA maximum. It features selectable gain of 6 dB or 12 dB via the GS pin, fully differential inputs, and a fast turn-on time of 9 ms.

Feature Summary

• Filterless Class-D architecture eliminates the need for external output filters when driving inductive transducers.
• Selectable internal gain configuration (6 dB or 12 dB) removes the requirement for external gain-setting resistors.
• Fully differential input capability allows direct connection to DACs without input coupling capacitors.
• Integrated pop-and-click noise protection circuitry ensures silent startup and shutdown transitions.

Applications

• Cellular phones
• Personal Digital Assistants (PDAs)
• Portable electronic devices

Procurement Notes

Verify the ordering suffix FCT1G corresponds to the 9-Pin Flip-Chip CSP package and tape & reel shipping format. Confirm the component is Pb-Free as indicated by the marking diagram. Ensure the application design accounts for the thermal resistance dependency on PCB heatsink area, as specified in the datasheet notes.

Selection Notes

Select this amplifier for applications requiring high efficiency and minimal external component count. It is suitable for battery-powered systems due to low quiescent current and wide supply voltage range. Verify that the load impedance matches the power delivery specifications, typically 4 Ω or 8 Ω BTL configurations.

Part Context

This component belongs to the NCP2821 family of filterless Class-D audio amplifiers. It is manufactured by onsemi and utilizes a 9-Pin Flip-Chip CSP package (Case 499AL). The device is optimized for space-constrained portable electronics, offering a compact solution compared to traditional Class-AB amplifiers.

Replacement Considerations

NCP2820AFCT2G

FAQ

How is the gain of the NCP2821 configured?

The gain is set internally via the GS pin. A logic high level selects 6 dB gain, while a logic low level selects 12 dB gain, eliminating the need for external resistors.

What is the purpose of the optional output filter?

While the amplifier is filterless, an optional LC filter can be added to further reduce high-frequency emissions if required by specific EMI regulations, though it is not necessary for basic operation.