Source: https://mokxi.com/parts/74hc00 Updated: 2026-09-27 Part # 74HC00 quad NAND Four NAND gates in a DIP-14, with supply pins and a real propagation delay. or see every part - 14 pins Drawn live by the editor's own code, at the size you see it. Reference ## Every one of its 14 pins Pin Role What it does 1A Input 1B Input 1Y Output 2A Input 2B Input 2Y Output GND Input or output 3Y Output 3A Input 3B Input 4Y Output 4A Input 4B Input VCC Input or output This part ## What it does The 74HC00 packages four independent two-input NAND gates in one 14-pin chip, with pin 14 as VCC and pin 7 as GND: real catalog pins that have to be wired before any gate does anything at all. Unpowered, every output sits high-impedance rather than at a defined level, which is the single most common reason a logic circuit built from real chips looks dead on first inspection. Each gate answers with a controlling-value rule: a NAND with a 0 on either input already knows its output is 1 regardless of what the other input is doing, even if that other input is unknown, and only needs both inputs resolved when neither is a controlling value. Every input change reaches the output 9 nanoseconds later, the datasheet’s typical figure, and that delay is inertial, so a pulse narrower than 9 nanoseconds never reaches the output at all. How it is modeled ## What is true about the 74HC00 quad NAND, here ### 74HC00: quad 2-input NAND gate The 7400: four independent NAND gates in one 14-pin DIP, pin 7 GND and pin 14 VCC. An input that is unknown or floating still gives a defined output when it could not change the answer: a 0 on either input of a NAND forces Y high whatever the other input is doing. Propagation delay: 9 ns typical, from either input to Y. See it in: NAND latch. ### Not modeled One typical delay, and nothing around it. Each chip carries a single propagation delay taken from its datasheet's typical column at VCC = 5 V, CL = 15 pF and 25 °C, and uses it for every path through the package. There is no minimum or maximum, no spread between the gates in one chip, no rise or fall time, no output slew and no dependence on supply voltage, load capacitance or temperature, all of which a real 74HC part has, and all of which a datasheet gives ranges for. On the 74HC595 the one figure is the STCP-to-Qn number used for SHCP and MR to Q7S as well, which the datasheet lists a nanosecond or two apart. No setup, hold or pulse-width checks. The 74HC74 and the 74HC595 take a clock edge whenever they see one; nothing here refuses data that changed too close to the edge or a clock pulse that was too narrow, and nothing warns about it. A real part would metastable or simply miss. No supply current, no output current limit and no bus contention damage. An output driving into another output is resolved as two drivers on one net; nothing gets hot. Sequential parts power up cleared rather than random, because a toggle divider fed Unknown never escapes it. See how faithfully a part behaves. From The 74HC logic family, in full. Projects ## See the 74HC00 quad NAND in a project More parts ## The rest of the bench Every one of these is drawn and simulated the same way. Full-size breadboard A real 0.1 inch grid with the rails and the center channel, 63 columns wide. Jumper wires Drag from any pin or hole to any other. Corners snap, and you can drag them. Power A supply rail at the voltage you choose. Ground The other end of every circuit. LED Lights when current flows. Five colors, and the brightness is what your eye would see. Resistor Any value you like, with the color bands drawn to match. ESP32-C3-DevKitM-1 A RISC-V board that runs your firmware at 160 MHz on the real memory map. Pushbutton A 12 mm tactile switch. Hold it while the simulation runs. Raspberry Pi Pico The RP2040 board on our own Cortex-M0+ core. Pick a program and press Run. Raspberry Pi Pico W Raspberry Pi Pico W (RP2040). The same board and the same pinout as a Pico, with the CYW43439 on it. The WiFi is simulated (no radio, no real internet), and the on-board LED, which hangs off that chip rather than off GP25, is driven through the same path. Everything else is the Pico. STM32F411 Black Pill The Black Pill on our own Cortex-M4 core. Pick a program and press Run. BBC micro:bit V2 The nRF52833 board with its 5x5 LED matrix, buttons A and B and a speaker. Wire the rings to a breadboard. See every part ## Wire up the 74HC00 quad NAND Open the editor and push it into the breadboard. It is free, and it runs on your own machine. Start building Open the editor