I am using a 2n2222 transistor and I have done the following calculations as shown in the attachment. However, as shown in the 2N2222 spec sheet attachment it says that the HFE should be determined by the corresponding ic calculations. If you look at my calculations, my ic is approximately 1.3 ma. April 2011 Doc ID 018729 Rev 1 1/10 10 2SD1047 High power NPN epitaxial planar bipolar transistor Features High breakdown voltage VCEO = 140 V Typical ft = 20 MHz Fully characterized at 125 oC NXP Semiconductors Product data sheet NPN switching transistor MMBT2222A DATA SHEET STATUS Notes 1. Please consult the most recently issued document before initiating or completing a design. 2. The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices.