Title 1. JTAG.pdf ✅

+91-9986194191 | www.vlsiguru.com | www.inskill.in JOINT TEST ACTION GROUP (JTAG) [IEEE 1149.1 std] NEED OF JTAG : • To minimize the no. of ports from top level. • To achieve boundary scan.
+91-9986194191 | www.vlsiguru.com | www.inskill.in To minimize no. of ports from top level LIST OF SOME IMPORTANT SIGNALS : TM edt_bypass_en int_mode ext_mode int_ltest_en ext_ltest_en mbist_bypass_en BIST_setup MBIST_PG_en These are just a list of important signals. There will be many more signals like these. If all these signals are to be controlled from top-level, then the no .of top level ports will increase drastically. So we use JTAG to internally control these signals. By using JTAG we need only 5 ports (TMS, TCLK, TRST, TDI, TDO) to control all the above signals.