BOM-fit check — what the 74HC245DBR brings to the bus
The SN74HC245DBR is an 8-bit non-inverting transceiver with 3-state outputs from TI's 74HC family — the workhorse bidirectional bus buffer for 5V and 3.3V logic domains that need to push and pull data across a backplane or memory bus without contention. Its 2V to 6V supply range means it can sit on a 3.3V rail and still talk to a 5V peripheral on the other side, as long as the output high level meets the receiving logic threshold — the 7.8mA drive on both high and low sides is enough for a few TTL loads or a short trace, but not a long cable run. Single-element 8-bit configuration keeps the pinout simple: one direction-control pin, one output-enable pin, and the A and B ports — the scorch mark on a dead board usually points to a shorted output pin on the port that was driving a capacitive load without series termination.
Package reality for the rework bench
The 20-SSOP package (0.209-inch body width, 5.30 mm) with 0.65 mm pitch is a standard SOIC footprint variant — hot-air rework at 260°C peak profile per J-STD-020, no prebake needed if the moisture-barrier bag is intact and the floor life hasn't been exceeded. Surface-mount only — no through-hole equivalent in this series; if the board was laid out for a DIP socket, this part needs an adapter or a layout spin.
Lifecycle and compliance — active, RoHS3, no PCN watch needed
The -40°C to 85°C industrial temperature range covers most panel and equipment environments; if the board lives in an engine bay or a freezer, the 125°C-rated SN74LV8T245PWR is the better fit.
