SN74HC21PWR from Texas Instruments, in a TSSOP-14. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	1A	input	Channel 1, Input A. Standard high-impedance CMOS logic input for the first 4-input AND gate. VIH ≥ 3.15 V @ VCC=4.5 V; VIL ≤ 1.35 V @ VCC=4.5 V.
2	1B	input	Channel 1, Input B. Standard high-impedance CMOS logic input for the first 4-input AND gate.
3	NC	unconnected	Not internally connected. Leave floating or tie to a defined level per board practice.
4	1C	input	Channel 1, Input C. Standard high-impedance CMOS logic input for the first 4-input AND gate.
5	1D	input	Channel 1, Input D. Standard high-impedance CMOS logic input for the first 4-input AND gate.
6	1Y	output	Channel 1, Output Y. Balanced CMOS push-pull output; 1Y = 1A · 1B · 1C · 1D. IOH/IOL rated ±4 mA at VCC=4.5 V and ±5.2 mA at VCC=6 V.
7	GND	power_in	Ground reference (0 V). Common return for VCC supply and all logic inputs/outputs.
8	2Y	output	Channel 2, Output Y. Balanced CMOS push-pull output; 2Y = 2A · 2B · 2C · 2D.
9	2A	input	Channel 2, Input A. Standard high-impedance CMOS logic input for the second 4-input AND gate.
10	2B	input	Channel 2, Input B. Standard high-impedance CMOS logic input for the second 4-input AND gate.
11	NC	unconnected	Not internally connected. Leave floating or tie to a defined level per board practice.
12	2C	input	Channel 2, Input C. Standard high-impedance CMOS logic input for the second 4-input AND gate.
13	2D	input	Channel 2, Input D. Standard high-impedance CMOS logic input for the second 4-input AND gate.
14	VCC	power_in	Positive supply. Recommended operating range 2 V to 6 V (nominal 5 V); absolute maximum 7 V. Bypass with a ceramic capacitor close to the pin.

Key specifications

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

Ordering variants

Same part, different packaging or reel option.

SN74HC21PWR
SN74HC21PWRD
SN74HC21PWRN
SN74HC21PWRNS
SN74HC21PWRJ
SN74HC21PWRFK

CAD (KiCad official)

Symbol: SN74HC21PWR
Footprint: Package_SO:TSSOP-14_4.4x5mm_P0.65mm
3D model: TSSOP-14 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`sn74hc21pwr.step`	194 KB	You want the bare part, or you mark your own boards.
`sn74hc21pwr-etched.step`	2.3 MB	You want the part with `SN74HC21PWR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 591 faces against 237 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

Datasheet: Texas Instruments datasheet (34 pp, sha256 d9553773c8d57248, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF