Quad RS-485/RS-422 driver in 16-SOIC
The SN75LBC174A16DW is a quad RS-485/RS-422 line driver from Texas Instruments, delivering 30 Mbps per channel over a 4.75 V to 5.25 V supply rail. With four drivers and zero receivers (4/0), this IC is a pure transmit-side buffer for differential bus interfaces — no receiver logic on chip. Housed in a 16-SOIC (0.295", 7.50 mm width) package, the surface-mount footprint matches the standard SOIC-16 narrow-body land pattern. The commercial temperature grade (0°C to 70°C) suits indoor control cabinets, telecom racks, and office equipment where ambient stays within that envelope.
Active production — no EOL watch needed
For BOM planning, the active status means no urgency to qualify a drop-in replacement; the supply channel is stable.
30 Mbps bus margin and supply range
At 30 Mbps, the driver can sustain a 33 ns bit period — enough margin for most RS-485/RS-422 links up to a few hundred metres. The 4.75 V to 5.25 V supply range (5 V nominal) sets the differential output voltage swing; running below 4.75 V may drop the output below the receiver threshold. The 4/0 driver count means this IC handles only the transmit side of a full-duplex bus. For a four-wire RS-422 link, one SN75LBC174A16DW covers all four transmit lines. For half-duplex RS-485, pair it with a quad receiver such as the SN75LBC174ADW.
