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More information is available about our Analysis Services and Support for Linear Technology models.

1. How do you evaluate end-of-life ("EOL") STABILITY performance for your linear regulator circuits?

a. We do not evaluate EOL Stability 0%
b. We ONLY TEST Beginning-of-life (BOL) Stability 54.2%
c. We use SPICE or another Analog Simulator 45.8%

2. If you test regulator stability, WHEN do you do it?

a. At the prototype stage 83.3%
b. Engineering Model stage 66.7%
c. Integrated System 12.5%

3. If you test regulator stability, HOW do you do it?

a. Transient Step Loading 87.5%
b. Bode Plots 75%
c. Non-invasively (Output Impedance) 20.8%
d. We generally don't 0%

4. Do you perform WCCA (worst case circuit analysis) on your linear regulators including stability, ripple rejection, step load, headroom, current limit, regulation, and startup?

a. No or rarely 12.5%
b. No, unless our customer requires us to perform the WCCA 0%
c. Yes but not all of the analyses mentioned 37.5%
d. Yes, most if not all of the analyses mentioned 50.0%

5. If you use SPICE to perform EOL regulator stability analysis do you:

a. Make your own regulator IC models 45.8%
b. Use LTxxx models to represent the RHxxx parts in your simulations (for example, use the LT1573 to model the RH1573) 58.3%
c. Tolerance the IC model itself (internal parameters like bandwidth, error amp gain, etc.) 50.0%
d. ONLY tolerance the parts external to the regulator 8.3%
e. Validate the IC model against Bench Test Data (as opposed to just the data sheet) 45.8%
f. Use "ladder models" (AVX Spitan/Kemet Spice) to model the capacitors 20.8%
g. Generally find "RLC" models acceptable for the capacitors 37.5%
h. Test the actual capacitor impedance/ESR and make your own "ladder" models? 29.2%

6. If/when you perform a Monte Carlo analysis,

How many cases do you normally run? cases
a. How many sigma (standard deviations) do you use to compute the performance range? Varies, 12-1000
b. We use the end points (worst simulation results to indicate the worst case performance). 73.3%

7. What test equipment do you use for stability (gain-phase) testing?
(Check all that apply)

a. Electronic load 54.2%
b. Ridley AP300 Network analyzer 20.8%
c. Venable Network Analyzer 25%
d. Agilent Network Analyzer 33.3%
e. Other Network Analyzer 20.8%

8. What is your job description?

a. Program Management 16.7%
b. Design Engineering 79.2%
c. Test Engineering 0%
d. Reliability Engineer 4.2%
e. Other 0%