SN65HVD21MDREP

Texas Instruments · RS-485 / RS-422 ICs · SOIC-8

SN65HVD21MDREP from Texas Instruments, in a SOIC-8. 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	R	output	Receiver data output: it reflects the state of the A and B bus inputs when RE is low, goes high-impedance when RE is high, and drives a high level within 250 µs after a bus fault (failsafe), with VOH of at least 4 V at IO = −8 mA and VOL of at most 0.4 V at IO = 8 mA.
2	RE	input	Active-low receiver output enable: the receiver is enabled when RE is low and disabled (R high-impedance) when RE is high, with VIH of at least 2·VCC and VIL of at most 0.8 V.
3	DE	input	Driver output enable, active high: the A and B outputs are enabled when DE is high and set high-impedance when DE is low, with VIH of at least 2 V (2·VCC) and VIL of at most 0.8 V.
4	D	input	Driver data input: when DE is high, a high on D drives A high and B low while a low drives A low and B high, with VIH of at least 2·VCC, VIL of at most 0.8 V, and input current limited to ±100 µA.
5	GND	power_in	Network ground terminal, the reference for all voltages on the device except the differential bus I/O voltage (absolute maximum rating −0.5 V to 7 V on VCC relative to this terminal).
6	A	bidirectional	Non-inverting driver output and receiver input of the differential bus port, rated for −20 V to 25 V common-mode voltage in recommended operation and −27 V to 27 V absolute maximum with 16 kV HBM ESD protection.
7	B	bidirectional	Inverting driver output and receiver input of the differential bus port, rated for −20 V to 25 V common-mode voltage in recommended operation and −27 V to 27 V absolute maximum with 16 kV HBM ESD protection.
8	VCC	power_in	Single 5-V supply input, with recommended operating range of 4.5 V to 5.5 V (nominal 5 V) and an absolute maximum of 7 V.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOIC-8
Category	Interface
Pins	8

CAD (KiCad official)

Symbol: SN65HVD21MDREP
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOIC-8 (KiCad packages3D, STEP)
3D model files: sn65hvd21mdrep-etched.step / sn65hvd21mdrep-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); sn65hvd21mdrep.step / sn65hvd21mdrep.glb are the bare package body.

Provenance

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

Datasheet: Texas Instruments datasheet (22 pp, sha256 d17ec4ff266f5c93, retrieved 2026-10-08, 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

# SN65HVD21MDREP

**Texas Instruments** · RS-485 / RS-422 ICs · SOIC-8

SN65HVD21MDREP from Texas Instruments, in a SOIC-8. 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 | R | output | Receiver data output: it reflects the state of the A and B bus inputs when RE is low, goes high-impedance when RE is high, and drives a high level within 250 µs after a bus fault (failsafe), with VOH of at least 4 V at IO = −8 mA and VOL of at most 0.4 V at IO = 8 mA. |
| 2 | RE | input | Active-low receiver output enable: the receiver is enabled when RE is low and disabled (R high-impedance) when RE is high, with VIH of at least 2·VCC and VIL of at most 0.8 V. |
| 3 | DE | input | Driver output enable, active high: the A and B outputs are enabled when DE is high and set high-impedance when DE is low, with VIH of at least 2 V (2·VCC) and VIL of at most 0.8 V. |
| 4 | D | input | Driver data input: when DE is high, a high on D drives A high and B low while a low drives A low and B high, with VIH of at least 2·VCC, VIL of at most 0.8 V, and input current limited to ±100 µA. |
| 5 | GND | power_in | Network ground terminal, the reference for all voltages on the device except the differential bus I/O voltage (absolute maximum rating −0.5 V to 7 V on VCC relative to this terminal). |
| 6 | A | bidirectional | Non-inverting driver output and receiver input of the differential bus port, rated for −20 V to 25 V common-mode voltage in recommended operation and −27 V to 27 V absolute maximum with 16 kV HBM ESD protection. |
| 7 | B | bidirectional | Inverting driver output and receiver input of the differential bus port, rated for −20 V to 25 V common-mode voltage in recommended operation and −27 V to 27 V absolute maximum with 16 kV HBM ESD protection. |
| 8 | VCC | power_in | Single 5-V supply input, with recommended operating range of 4.5 V to 5.5 V (nominal 5 V) and an absolute maximum of 7 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-8 |
| Category | Interface |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `SN65HVD21MDREP`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `sn65hvd21mdrep-etched.step` / `sn65hvd21mdrep-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sn65hvd21mdrep.step` / `sn65hvd21mdrep.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/sn65hvd21m-ep) (22 pp, sha256 `d17ec4ff266f5c93`, retrieved 2026-10-08, 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/sn65hvd21mdrep-datasheet.pdf)