jackcartersmith/Speech256
1
0
Fork 0
mirror of https://github.com/trcwm/Speech256.git synced 2025-06-07 16:48:32 +02:00
Code Issues Projects Releases Wiki Activity

Updated DAC lowpass filter in documentation

Browse Source
This commit is contained in:
Niels Moseley 2017-10-26 17:57:09 +02:00
parent 8afd1af0a7
commit 42ad37a956
1 changed files with 8 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
boards/Digilent DE0/README.md
View File

@ -2,17 +2,17 @@
* Altera EP3C16F484C6 FPGA
The DAC output is the UART_TX pin. It _really_ needs a 5kHz lowpass filter, otherwise you'll be deafened/greeted by a very loud 10kHz PWM carrier. Try a 330 ohm series resistor, followed by a 100nF capacitor to ground:
The DAC output is the UART_TX pin. It _really_ needs a 5kHz lowpass filter, otherwise you'll be deafened/greeted by a very loud 10kHz PWM carrier. Try two sections of a 1K ohm series resistor, followed by a 100nF capacitor to ground:
```
UART_TX pin ----RRRRR---------o OUTPUT
|
C
C
C
|
GND
UART_TX pin ----RRRRR--------RRRRR---------o OUTPUT
| |
C C
C C
C C
| |
GND GND
```