OPA454: How to Increasing Output Current?

Hi Lahm,

this is my simulation result:

lahm_opa454.TSC

Kai

The Spice models of MJE15003 and MJE15004 are from here:

I have taken the "Spice3" models. After changing the file ending to .cir, I imported them into TINA-TI.

Kai

Thanks a lot for your answer, but frankly I am still confused about my questions. Could you please be more specific ?

 Hi user6304246,

Thanks Kai for presenting the schematic. 

Input: Voltage  ranges from -5V to +5V. (please verify)

OUtput: The output P01‘ voltage is required from -45V~0V~+45V （60hz） according to  DAC_P01. 

1) Is the circuit above capable enough to charge the capacitor? 

It should be able to.

2) When EN is 3.3V  the circuit works normally, and when EN is  GND level the circuit shutdown?

Per normal operation, the E/D (Enable/Disable) pin needs to be +2.5V above E/D Com pin. Below E/D Com + 0.65V, the IC will be a shutdown state. 

3) How to choose  transistor Q1&Q2 and  resistor R3&R6&R8? what's the key parameter need to be calculated  first？Any mos to recommend to replace transistor?

Your circuit is running inverting op amp configuration. If your input is 5V, and output requires 45V, then you will need Gain of 45/5=9 V/V. With +/-50V at the supply rails, it seems that it may meet power requirements. 

Mosfet will work as well. Please let us know what you want. Enclosed is an example of the your simulation with slight modification.

/cfs-file/__key/communityserver-discussions-components-files/14/OPA454-800mA-06082020.TSC

Best,

Raymond