LM336 model is available with PSpice installation. You can find this model in vr.lib and logical symbols in vr.olb. About bringing a model a new model from an external source in PSpice - Please refer Appendix C "Importing Spice Models" in PSpice user guide.
LM336 model is available with PSpice installation. You can find this model in vr.lib and logical symbols in vr.olb. About bringing a model a new model from an external source in PSpice - Please refer Appendix C "Importing Spice Models" in PSpice user guide.
You can refer an excellent app note from TI - http://www.ti.com/lit/an/sloa070/sloa070.pdf