# Om amp power supply voltage

by unknown_2
Tags: power, supply, voltage
 P: 29 Hi, i'm trying to understand how to correct when you put Vcc as 10V your max output is like 9.18V. Is there a factor on the data sheet or what? I'm trying to build a bi-state multivibrator to generate a 10V peak value but it's being saturated. thanks.
 P: 17 Vout = A(Vp-Vn) A = open loop gain specified by op amp (usually around x10^5) Vp = non-inverting input Vn = inverting input Vcc is normally around tens of volts. Have you tried increasing it to change the range? Based on the eq above, in the linear range: -Vcc< Vout < -Vcc
 P: 4,667 What is your output circuit? Bob S
P: 29

## Om amp power supply voltage

well open loop gain is so big that it'll, ideally saturate at Vcc and -Vcc. but practically it'll saturate at a lower value ( 10V saturate to 9.11V). i want to increase Vcc and -Vcc such that i can compensate for this decrease in output voltage. so in order to saturate at say 10V I need to increase Vcc and -Vcc to a higher number like 10.66V to compensate.
 P: 29 looking for a way to calculate it so i can apply it to different Vcc voltages
 P: 4,667 Why don't you use a voltage comparator with an npn open collector output with a resistor pullup, or a pnp collector output with the emitter tied to Vcc? What circuit are you using? Bob S
 P: 29 i'm limited to resistors, opamps and capacitors. My full circuit it a waveform generator. the bi-state multivibrator output is acting as a square wave generator. and i want a 8vp-p value. but if i put 4V and -4V for Vcc and -Vcc it'll def be saturated and inaccurate.
 P: 4,667 What you could use is a rail-to-rail-output op amp like the Linear LTC1152 chip in an 8-pin DIP package http://www.google.com/url?sa=t&sourc...mhjOxOgKsCOx_g You could also use two bipolar transistors; a pnp pullup to Vcc and a npn pulldown to Vee, with their collectors tied together. Bob S
Mentor
P: 11,898
 Quote by unknown_2 Hi, i'm trying to understand how to correct when you put Vcc as 10V your max output is like 9.18V. Is there a factor on the data sheet or what? I'm trying to build a bi-state multivibrator to generate a 10V peak value but it's being saturated. thanks.
I don't know if all datasheets follow the same convention, but for the TL08x series, TI uses VOM for the maximum output voltage. Look at Figure 10 on p. 10 at