518 TT25 3B DAC and RingO
518 : TT25 3B DAC and RingO
- Author: Luke McCubbin
- Description: First Tapeout Run using Harald Pretl and Jakob Ratschenberger's tt05 analog design
- GitHub repository
- Open in 3D viewer
- Clock: 0 Hz
How it works
Credit to Harald Pretl and Jakob Ratschenberger, Institute for Integrated Circuits, Johannes Kepler University, Linz, Austria for the design of this circuit for TinyTapeout 5 Analog test (500kHz ring oscillator and 3-bit R-2R DAC) .
Nominal supply voltage: 1.8V
Two test outputs:
Clock output (rail-rail) at ca. 500kHz
DAC voltage vout=1.8V / 8 * in (0...7)
How to test
Apply digital bit input to input bits 0-2 and measure output with voltmeter/osciloscope
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | dac0 | ||
| 1 | dac1 | ||
| 2 | dac2 | ||
| 3 | tg_dac | ||
| 4 | |||
| 5 | tg_ro | ||
| 6 | tg_short | ||
| 7 |
Analog pins
ua | PCB Pin | Internal index | Description |
|---|---|---|---|
| 0 | B5 | 11 | clk |
| 1 | B0 | 6 | dac |