# SN74HC21QPWRG4Q1

**Texas Instruments** · Logic Gates · TSSOP-14

SN74HC21QPWRG4Q1 from Texas Instruments, in a TSSOP-14. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | 1A | input | Input A of gate 1; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 2 | 1B | input | Input B of gate 1; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 3 | NC | unconnected | No internal connection. |
| 4 | 1C | input | Input C of gate 1; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 5 | 1D | input | Input D of gate 1; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 6 | 1Y | output | Output of gate 1; can drive up to ten LSTTL loads with ±4 mA output drive at 5 V. |
| 7 | GND | power_in | Ground reference for the device. |
| 8 | 2Y | output | Output of gate 2; can drive up to ten LSTTL loads with ±4 mA output drive at 5 V. |
| 9 | 2A | input | Input A of gate 2; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 10 | 2B | input | Input B of gate 2; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 11 | NC | unconnected | No internal connection. |
| 12 | 2C | input | Input C of gate 2; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 13 | 2D | input | Input D of gate 2; the gate performs Y = A • B • C • D in positive logic, and input current is 1 µA max. |
| 14 | VCC | power_in | Supply voltage, 2 V to 6 V wide operating range. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | TSSOP-14 |
| Category | Logic |
| Pins | 14 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Supply voltage range | VCC | -0.5 |  | 7 | V |  | 2 |
| Input clamp current | IIK | -20 |  | 20 | mA | VI < 0 or VI > VCC | 2 |
| Output clamp current | IOK | -20 |  | 20 | mA | VO < 0 or VO > VCC | 2 |
| Continuous output current | IO | -25 |  | 25 | mA | VO = 0 to VCC | 2 |
| Continuous current through VCC or GND |  | -50 |  | 50 | mA |  | 2 |
| Storage temperature range | Tstg | -65 |  | 150 | °C |  | 2 |
| Supply voltage | VCC | 2 | 5 | 6 | V |  | 2 |
| High-level input voltage | VIH | 1.5 |  |  | V | VCC = 2 V | 2 |
| High-level input voltage | VIH | 3.15 |  |  | V | VCC = 4.5 V | 2 |
| High-level input voltage | VIH | 4.2 |  |  | V | VCC = 6 V | 2 |
| Low-level input voltage | VIL |  |  | 0.5 | V | VCC = 2 V | 2 |
| Low-level input voltage | VIL |  |  | 1.35 | V | VCC = 4.5 V | 2 |
| Low-level input voltage | VIL |  |  | 1.8 | V | VCC = 6 V | 2 |
| Input voltage | VI | 0 |  |  | V | max = VCC | 2 |
| Output voltage | VO | 0 |  |  | V | max = VCC | 2 |
| Input transition rise/fall time | Δt/Δv |  |  | 1000 | ns | VCC = 2 V | 2 |
| Input transition rise/fall time | Δt/Δv |  |  | 500 | ns | VCC = 4.5 V | 2 |
| Input transition rise/fall time | Δt/Δv |  |  | 400 | ns | VCC = 6 V | 2 |
| Operating free-air temperature | TA | -40 |  | 125 | °C |  | 2 |
| High-level output voltage | VOH | 1.9 | 1.998 |  | V | IOH = -20 µA, VI = VIH or VIL, VCC = 2 V, TA = 25°C | 3 |
| High-level output voltage | VOH | 4.4 | 4.499 |  | V | IOH = -20 µA, VI = VIH or VIL, VCC = 4.5 V, TA = 25°C | 3 |
| High-level output voltage | VOH | 5.9 | 5.999 |  | V | IOH = -20 µA, VI = VIH or VIL, VCC = 6 V, TA = 25°C | 3 |
| High-level output voltage | VOH | 3.98 | 4.3 |  | V | IOH = -4 mA, VI = VIH or VIL, VCC = 4.5 V, TA = 25°C | 3 |
| High-level output voltage | VOH | 3.7 |  |  | V | IOH = -4 mA, VI = VIH or VIL, VCC = 4.5 V, TA = -40°C to 125°C | 3 |
| High-level output voltage | VOH | 5.48 | 5.8 |  | V | IOH = -5.2 mA, VI = VIH or VIL, VCC = 6 V, TA = 25°C | 3 |
| High-level output voltage | VOH | 5.2 |  |  | V | IOH = -5.2 mA, VI = VIH or VIL, VCC = 6 V, TA = -40°C to 125°C | 3 |
| Low-level output voltage | VOL |  | 0.002 | 0.1 | V | IOL = 20 µA, VI = VIH or VIL, VCC = 2 V, TA = 25°C | 3 |
| Low-level output voltage | VOL |  |  | 0.1 | V | IOL = 20 µA, VI = VIH or VIL, VCC = 2 V, TA = -40°C to 125°C | 3 |
| Low-level output voltage | VOL |  | 0.001 | 0.1 | V | IOL = 20 µA, VI = VIH or VIL, VCC = 4.5 V, TA = 25°C | 3 |
| Low-level output voltage | VOL |  | 0.17 | 0.26 | V | IOL = 4 mA, VI = VIH or VIL, VCC = 4.5 V, TA = 25°C | 3 |
| Low-level output voltage | VOL |  |  | 0.4 | V | IOL = 4 mA, VI = VIH or VIL, VCC = 4.5 V, TA = -40°C to 125°C | 3 |
| Low-level output voltage | VOL |  | 0.15 | 0.26 | V | IOL = 5.2 mA, VI = VIH or VIL, VCC = 6 V, TA = 25°C | 3 |
| Input current | II | -100 | 0.1 | 100 | nA | VI = VCC or 0, VCC = 6 V, TA = 25°C | 3 |
| Input current | II | -1000 |  | 1000 | nA | VI = VCC or 0, VCC = 6 V, TA = -40°C to 125°C | 3 |
| Supply current | ICC |  | 2 | 40 | µA | VI = VCC or 0, IO = 0, VCC = 6 V, max at TA = -40°C to 125°C | 3 |
| Supply current | ICC |  |  | 20 | µA | VI = VCC or 0, IO = 0, VCC = 6 V, max at TA = -40°C to 85°C | 3 |
| Input capacitance | Ci |  | 3 | 10 | pF | VCC = 2 V to 6 V, TA = 25°C | 3 |
| Propagation delay time | tpd |  | 44 | 110 | ns | A, B, C, or D to Y, CL = 50 pF, VCC = 2 V, TA = 25°C | 3 |
| Propagation delay time | tpd |  |  | 165 | ns | A, B, C, or D to Y, CL = 50 pF, VCC = 2 V, TA = -40°C to 125°C | 3 |
| Propagation delay time | tpd |  | 14 | 22 | ns | A, B, C, or D to Y, CL = 50 pF, VCC = 4.5 V, TA = 25°C | 3 |
| Propagation delay time | tpd |  |  | 33 | ns | A, B, C, or D to Y, CL = 50 pF, VCC = 4.5 V, TA = -40°C to 125°C | 3 |
| Propagation delay time | tpd |  | 11 | 19 | ns | A, B, C, or D to Y, CL = 50 pF, VCC = 6 V, TA = 25°C | 3 |
| Propagation delay time | tpd |  |  | 28 | ns | A, B, C, or D to Y, CL = 50 pF, VCC = 6 V, TA = -40°C to 125°C | 3 |
| Output transition time | tt |  | 29 | 75 | ns | Y, CL = 50 pF, VCC = 2 V, TA = 25°C | 3 |
| Output transition time | tt |  |  | 110 | ns | Y, CL = 50 pF, VCC = 2 V, TA = -40°C to 125°C | 3 |
| Output transition time | tt |  | 10 | 15 | ns | Y, CL = 50 pF, VCC = 4.5 V, TA = 25°C | 3 |
| Output transition time | tt |  |  | 22 | ns | Y, CL = 50 pF, VCC = 4.5 V, TA = -40°C to 125°C | 3 |
| Output transition time | tt |  | 8 | 13 | ns | Y, CL = 50 pF, VCC = 6 V, TA = 25°C | 3 |
| Output transition time | tt |  |  | 19 | ns | Y, CL = 50 pF, VCC = 6 V, TA = -40°C to 125°C | 3 |
| Package thermal impedance, PW package | θJA |  | 113 |  | °C/W | PW package, JESD 51-7 | 2 |

## CAD (KiCad official)

- Symbol: `SN74HC21QPWRG4Q1`
- Footprint: `Package_SO:TSSOP-14_4.4x5mm_P0.65mm`
- 3D model: TSSOP-14 (KiCad packages3D, STEP)
- 3D model files: `sn74hc21qpwrg4q1-etched.step` / `sn74hc21qpwrg4q1-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sn74hc21qpwrg4q1.step` / `sn74hc21qpwrg4q1.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/sn74hc21-q1) (15 pp, sha256 `6f014d9be4b93dfe`, retrieved 2026-10-17, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/sn74hc21qpwrg4q1-datasheet.pdf)