Other Parts Discussed in Thread: TINA-TI,
Tool/software: TINA-TI or Spice Models
• 30-degree phase margin is stable? But not in mass production.
• In above circuit, by adding a C1 220pF as capacitive load at the op amp output, there is a gain peaking about 7-dB meaning phase margin left about 20~30-degree.
• Could I say this circuit (single case) is stable?
• But considering mass production, there might be op amp internal compensation cap +/-20% variation in full temperature range and external component tolerance +/-20%.
It is better to keep phase margin > 45- degree as a rule of thumb.