BTM510/511 Multimedia Module

Datasheet

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Note:

1. Reset input is active low. Input is pulled up to VDD_IN via 22 k. Minimum reset pulse width is 5 ms.

2. LED drive pins are open drain outputs, so the external circuit to the right should be used. The voltage on

the module pad should be maintained below 0.5 V in which case the RON of the FET is around 20 Ω. If this

condition is met, the current flowing through the diode is as follows:

Where VF is the forward bias voltage of the LED.

Figure 1: Microphone mode

The input impedance on the microphone inputs (in microphone mode) is typically 6kΩ. The audio input is

designed for use with inputs of between 1 μA and 10 μA at 94 dB SPL. If the biasing resistors are set to 1 kΩ, this

implies a microphone with sensitivity in the range -40 dBV to -60 dBV.

The low pass filter elements formed by the inductor and capacitor are necessary to eliminate RF pick up on the

microphone inputs and should be placed as close to the module as possible. When operating in line input mode,

the input can be connected directly to the module input pins in either single or double ended configuration as

follows:

Figure 2: Line input mode