Connecting to database through username,passphrase and private key on PgAdmin

[Yambu <hyambu@xxxxxxxxx>]

  Hello

May i please know how i can connect to a db server using pgAdmin. How do i use the combination of username,passphrase and private key .

Below is when i connect using putty. I then login as postgres user and connect to the database.

login as: user1
Authenticating with public key "*******"
Passphrase for key "*****":

regards