Data Sheet

IDC7 Bluetooth Module
Model: IDC747
Page: 15 Copyright IOT747 Ref: IDC747-DTS-V003
IOT747, 122 Ross Street, Cambridge, CB1 3BU, United Kingdom
Check www.iot747.com for updates. Email: [e-mail] Back to TOC
IDC747 Module
Product Information Data Sheet
Ref: IDC747-DTS-V003
Latest Update: July 20, 2021
122 Ross Street, CB13BU
Cambridge, United Kingdom
www.iot747.com
Example of a filter circuit or a Ferrite bead:
Some amplifiers do not support “capless” operation and require ac coupling on the input and
output of the amplifier. Series capacitance can introduce clicks and pops during turn off and
turn on as voltage transients occur across the capacitors causing audible spikes on the
audio output.
Choice of capacitors used in these configurations is important, avoid using ceramic
capacitors as these tend to have high voltage coefficients. Use low voltage coefficients
capacitors such as tantalum or electrolytic capacitors to reduce low frequency distortion
effects.
In differential mode the tolerance of the source and feedback resistors which set the gain of
an amplifier is important. 1% resistors give a 40dB CMRR whereas 0.1% resistors give a
60dB CMRR. Use 0.1% resistor arrays for even better performance.