Hi experts:
Customer are using simulation software hypwerlynx V2.7 simulate TDA4VM LPDDR4 Signal Integrity. At our excel parameter calculate tools the driver strength pull-up/down use 34.3 ohm. The software SBL driver.psdk_rtos_auto_j7_07_00_00_11/pdk_jacinto_07_00_00/packages/ti/board/src/j721e_evm/include/board_ddrRegInit.h line 2224-2228 configure the driver strength is largest one.
Follow IBIS module just LPDDR4x can use 34.3 ohm pull-up/pull-down value. LPDDR4 just support 40ohm pull resistor. Customer use the same as spracn9a.pdf page 20. (- lpddr4_ocd_40p_40n, lpddr4_ocd_40p_40n_diff)
The question is that whether TDA4VM default software LPDDR4 driver strength setting is wrong, because it do not meet LPDDR4 spec and ibis module?
Best Regards!
han tao