SN74LS31D
SN74LS31DE4
SN74LS31DG4
SN74LS31DR
SN74LS31DRE4
SN74LS31DRG4
SN74LS31N
SN74LS31NE4
SN74LS31NS
SN74LS31NSE4
19129491934(手机优先微信同号)