Quad 2-input NAND gate with open-collector outputs — what this part is and where it fits
The Texas Instruments SN74F38N is a 74F-series quad 2-input NAND gate with open-collector outputs, packaged in a 14-pin through-hole DIP (0.300", 7.62mm). It contains four independent NAND gates, each with two inputs, and the open-collector output stage allows wired-OR connections, level shifting, and direct drive of loads such as LEDs, relays, or bus lines that require a pull-up to a different voltage rail. The part operates from a 4.5V to 5.5V supply and is rated for the commercial temperature range of 0°C to 70°C, making it a fit for indoor equipment, office electronics, appliance control boards, and legacy 5V logic systems where through-hole assembly is still used.
64 mA sink — the headline rating that drives the selection
The open-collector outputs are rated to sink up to 64 mA per channel, which is the key parametric for BOM fit. That sink current is what lets this gate directly drive a small relay coil, a panel LED with a series resistor, or a logic-level bus pulled up to a higher voltage. The high-level output current is listed as "-" because the output transistor is off in the high state — the pull-up resistor (external, required) determines the high-level current. The 64 mA rating is per-output; the package total dissipation still needs checking against the load duty cycle, but for typical indicator or bus applications it provides comfortable margin.
12.5 ns propagation delay — timing margin in 5V logic
Maximum propagation delay is specified at 12.5 ns with a 5V supply and 50 pF load. This is the 74F family's speed grade — faster than the original 74LS series but not as fast as 74AC or 74AHC. For a 5V synchronous bus running at 10–20 MHz, the 12.5 ns delay leaves adequate setup-and-hold margin through one gate layer. If the design uses multiple cascaded open-collector stages with pull-up resistors, the RC time constant of the pull-up and load capacitance will dominate the total delay, so the 12.5 ns spec is the gate-only floor.
Active production — no LTB risk on this line item
The SN74F38N carries an Active product status and is ROHS3 compliant. For a BOM line that needs a through-hole 5V NAND gate with open-collector outputs, this part is a stable, current-production choice with no supply discontinuity risk. The 74F series has broad distribution support, and the DIP package continues to be manufactured for industrial and legacy-support demand.
Input logic levels and 5V compatibility
The input logic levels are standard TTL: low is 0.8V maximum, high is 2V minimum. This means the SN74F38N is directly compatible with 5V TTL and 5V CMOS logic families that output TTL-compatible levels (such as 74LS, 74S, 74F, and 5V 74HCT). It will also accept 3.3V logic outputs as long as the high-level voltage exceeds 2V — most 3.3V CMOS outputs at 3.0V or above meet this threshold. The supply range of 4.5V to 5.5V keeps it firmly in the 5V logic domain.
Package and mounting — through-hole DIP for prototyping and legacy boards
The 14-pin DIP (0.300", 7.62mm) with through-hole mounting is the traditional dual-inline package. It fits standard 0.1-inch pitch prototyping boards, wire-wrap panels, and legacy PCB layouts that were designed before surface-mount became dominant. The supplier device package is listed as 14-PDIP. For a repair, retrofit, or small-batch production run that uses through-hole assembly, this is the correct ordering code — the surface-mount variants (SN74F38D, SN74F38NSR) carry different suffixes.
Quiescent current and power budget
Maximum quiescent supply current is 7 mA for all four gates combined. At 5V, that is 35 mW quiescent dissipation — negligible in most designs. The dynamic power depends on the switching frequency and load capacitance, but for a typical gate used at a few megahertz, the total dissipation stays well under 100 mW. No heatsinking is needed for the DIP package in normal ambient conditions.