MIKROE Speaker Click is a compact add-on board that contains an audio power amplifier with a high-quality audio reproduction. This board features the MAX9717, a 1.4W mono bridge-tied load (BTL) architecture audio power amplifier from Maxim Integrated. It delivers 1.4W continuous power into a 4Ω load from a single +5V supply, or 350mW continuous power into an 8Ω load while operating from a single +3.3V supply. Also, the MAX9717 has an adjustable gain amplifier and a headphone sense input that senses headphone connection to the device, muting the speaker while driving the headphone as a single-ended load. This Click board™ is suitable for portable audio applications such as PDAs and portable devices where space and cost are of great importance.

Speaker Click as its foundation uses the MAX9717, a 1.4W mono bridge-tied load (BTL) architecture audio power amplifier with a high-quality audio reproduction from Maxim Integrated. It delivers 1.4W continuous power into a 4Ω load from a single +5V supply, or 350mW continuous power into an 8Ω load while operating from a single +3.3V supply. This device features Maxim’s industry-leading, comprehensive click-and-pop suppression that reduces audible clicks and pops during Start-Up and Shutdown sequence. Output signal reproduction is possible through the onboard speaker, as well as through the headphone jack located on the bottom side of this Click board™.

Speaker Click communicates with MCU using two GPIO pins routed on the PWM and INT pins of the mikroBUS™ socket labeled B/S and PWR. The MAX9717 features a low-power shutdown mode that reduces quiescent current consumption to 10nA. Entering shutdown mode is possible through the PWR pin, which disables the bias circuitry, and forces the amplifier outputs to GND through an internal 20kΩ resistor. Driving the PWR to a low logic state will cause MAX9717 to enter shutdown mode while the high state will perform a normal operation.

As mentioned before, this Click board™ has an onboard speaker, a 20mm 4Ω Premium Micro Transducer for sound reproduction. This speaker features a neodymium-iron-boron magnet, a light aluminum cone, and a high-temperature polycarbonate frame together with low resonant frequencies and a full-range bandwidth. Also, the MAX9717 features a headphone sense input pin, labeled as B/S, that senses headphone connection to the device through a 3.5mm jack connector labeled as HEADPHONES. This feature is muting the speaker while driving the headphone as a single-ended load. An adjustable potentiometer labeled as GAIN serves to adjust the gain of the MAXS9717‘s internal amplifier.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it allows both 3.3V and 5V capable MCUs to use the GPIO lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

• Interface: GPIO
• Compatibility: mikroBUS™
• Dimensions: 57.15 x 25.4mm
• Input Voltage: 3.3V or 5V

• Schematic
• MAX9717 Datasheet
• mikroSDK
• GitHub