I2S Audio Interface Timing Calculator
Calculate I2S bit clock (BCLK), word clock (LRCLK/WCLK), and data rate for audio interfaces at any sample rate, bit depth, and channel count.
Formula
BCLK = F_s \times N_{bits} \times N_{ch}
Reference: Philips I2S Bus Specification, 1996
How It Works
I2S (Inter-IC Sound) is a digital audio communication protocol used in digital audio transmission between integrated circuits. The protocol defines precise timing relationships between bit clock (BCLK), word clock (LRCLK), and master clock (MCLK), which determine the audio data transmission characteristics. These timing parameters are critical for ensuring accurate digital audio signal representation across different sampling rates and bit depths.
Worked Example
Problem: Calculate the required BCLK for a stereo 24-bit audio stream at 96 kHz sampling rate Solution: 1. Sampling frequency (fs) = 96 kHz 2. Bit depth = 24 bits 3. Channels = 2 (stereo) 4. BCLK = 96,000 Hz × 24 bits × 2 channels 5. BCLK = 4,608,000 Hz (4.608 MHz)
Practical Tips
- ✓Always verify MCLK is an appropriate multiple of the sampling rate
- ✓Use standard multiples like 256×fs or 512×fs for MCLK
- ✓Ensure data setup times meet I2S specification requirements
Common Mistakes
- ✗Incorrect calculation of bit clock frequency
- ✗Misunderstanding the relationship between sampling rate and BCLK
- ✗Neglecting to consider the number of audio channels
Frequently Asked Questions
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