## LM4880-SH2-R: Electronic Specifications and Overview The **LM4880-SH2-R** is a dual audio power amplifier primarily designed for headphone applications. It is part of the "Boomer" series, known for high-quality audio reproduction with minimal external components. --- ### 1. Key Technical Specifications The following table summarizes the core electrical characteristics of the LM4880: | Parameter | Specification | | :--- | :--- | | **Output Power** | 250mW (per channel) into 8Ω | | **Supply Voltage Range** | 2.7V to 5.5V | | **THD + N** | 0.1% (at 1kHz) | | **Shutdown Current** | 0.7µA (typical) | | **PSRR** | 52dB at 1kHz | | **Package Type** | SOP-8 (SH2 suffix) | --- ### 2. Core Features * **Unity-Gain Stable:** The amplifier can be configured for various gain settings without oscillating. * **Low Shutdown Current:** The device features a shutdown mode that reduces power consumption significantly, making it ideal for battery-operated devices. * **No Bootstrap Capacitors:** The design eliminates the need for bulky output coupling capacitors or bootstrap capacitors in some configurations, saving PCB space. * **Click and Pop Suppression:** Integrated circuitry minimizes audible noise during power-up and power-down cycles. --- ### 3. Pin Configuration (SOP-8) | Pin Number | Name | Function | | :--- | :--- | :--- | | 1 | **Shutdown** | Logic high shuts down the device | | 2 | **Input A** | Inverting input for channel A | | 3 | **Input B** | Inverting input for channel B | | 4 | **Output A** | Audio output for channel A | | 5 | **Output B** | Audio output for channel B | | 6 | **Vdd** | Positive Supply | | 7 | **GND** | Ground | | 8 | **BYPASS** | Tap to Vdd/2 for bias stability | --- ### 4. Typical Application Circuit To implement the LM4880, a simple closed-loop configuration is typically used: ```text Input Signal -> [Input Capacitor Ci] -> [Input Resistor Ri] -> Pin 2/3 Feedback Resistor Rf -> Connected between Pin 4/5 and Pin 2/3 ``` **Gain Calculation:** The gain of the amplifier is determined by the ratio of the feedback resistor ($R_f$) to the input resistor ($R_i$): `Gain = - (Rf / Ri)` --- ### 5. Common Applications * Portable electronic devices (MP3 players, handheld games). * Laptop and desktop computer audio. * Headphone amplifier modules. * Mobile communication devices.