4.3.4 Applications

Next: 5. ULP-Compatible Mixed Analog Up: 4.3 A Table-Based Device Previous: 4.3.3 Model Function and

4.3.4 Applications

Figure 4.11 shows the simulated switching transients of an RS flip-flop designed in a 0.5V ultra-low-power technology [61]. The same technology can be used to build OPAMPs operating at even lower supply voltages. In Fig. 4.12 simulation results of a ring-oscillator obtained with this model are compared against device-level simulations of the circuit with MINIMOS-NT [72]. The frequency error is 1.7% and the amplitude error is $<2\rm dB$ (1st-5th harmonic). Simulations of analog and mixed analog digital circuits are documented in Chapter 5.

**Figure 4.11:** RS flip-flop switching transients $\ensuremath{V_{\mathit{DD}}}\xspace =\rm0.5V$
$\includegraphics[scale=1.0]{rsff.ps}$ $\includegraphics[scale=1.0]{rsff.eps}$

**Figure 4.12:** 5-stage ring oscillator 0.2V ULP technology: circuit simulation MODEL5 vs. device-level simulation MINIMOS-NT
$\includegraphics[scale=1.0]{ro5-02-t.eps}$ $\includegraphics[scale=1.0]{ro5-02-s.eps}$

G. Schrom