about ICs part numbers

hello guyes ...

now if i want to know the specifications of a certian IC that i know its part number (for example SN7447) , i can get its datasheet from the internet and look its characteritsics and features ...

But how can i know the part numbre of an IC or a transistor of certian characteritsics ... i.e; i want to know the transistor part number for which beta dc=170 and early voltage of 100 V ... how can i get the part number of such a transistor ...?

plz help and thx

digikey.com
search for "transistor"
select "Transistor - Single, Bipolar Junction"
Choose: current Rating, Manufacturer, Package, PNP/NPN, Voltage (you can shoose a range of current or a single value)

Most Manufacturers have a selector guide. Some distributors have a selector guide.

thx ronsimpson for the site ...

Also, are you talking about the minimum DC gain in general or the gain at a specific current?

it doesn't matter hero, i am asking about how to get the part number of any component that meets specific characterisitcs and features, and the mentioned gain is just as example .... another example may be: What is the part number of a FET Op Amp ..??!!