jutek
Full Member level 4
ldo opamp
hello
let me know if i am wrong or not.
under stable vdd condition the opamp's gain should change with the load changes or be stable?
when i am simulating the LDO i do ac open loop analysis with different loads. Power supply is 1.3 V
after that i checked the opamp's gain and saw that for 1mA opamp's gain is higher than for 100mA
but with 3.3 vdd the situation is reciprocal, the gain is higher for 100mA
i surely check it after opamp, i know that pass device's gain changes with load if works in saturation.
maybe it is related to differencies at the inputs?
vref is 0.8 and the second input comes from output and the gain would be stable if output is 0.8 but is not.
what do you think ?
regards
hello
let me know if i am wrong or not.
under stable vdd condition the opamp's gain should change with the load changes or be stable?
when i am simulating the LDO i do ac open loop analysis with different loads. Power supply is 1.3 V
after that i checked the opamp's gain and saw that for 1mA opamp's gain is higher than for 100mA
but with 3.3 vdd the situation is reciprocal, the gain is higher for 100mA
i surely check it after opamp, i know that pass device's gain changes with load if works in saturation.
maybe it is related to differencies at the inputs?
vref is 0.8 and the second input comes from output and the gain would be stable if output is 0.8 but is not.
what do you think ?
regards
