MAX3078EM from HGSEMI, in a SOP-8. 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	RO	output	Receiver output. When /RE is low, RO is high if (A-B) ≥ -50mV and low if (A-B) ≤ -200mV. Fail-safe pulls RO high when the bus is open or shorted. CMOS logic level output.
2	/RE	input	Receiver output enable (active low). RO is enabled when /RE is low; RO is high-impedance when /RE is high. Driving /RE high while DE is low places the device into low-power shutdown mode. Hot-swap input structure.
3	DE	input	Driver output enable (active high). Driver outputs A,B are enabled when DE is high; outputs are high-impedance when DE is low. Driving DE low while /RE is high places the device into low-power shutdown mode. Hot-swap input structure.
4	DI	input	Driver data input. When DE is high, a logic low on DI drives A low and B high; a logic high on DI drives A high and B low. CMOS input (V_IH ≥ 2V, V_IL ≤ 0.8V).
5	GND	power_in	Ground reference (0V).
6	A	bidirectional	Non-inverting RS-485/RS-422 bus line. Acts as receiver non-inverting input and driver non-inverting output (half-duplex). Absolute range -7V to +12V, ±16kV IEC 61000-4-2 ESD protected. Receiver input impedance ≥96kΩ (1/8 unit load).
7	B	bidirectional	Inverting RS-485/RS-422 bus line. Acts as receiver inverting input and driver inverting output (half-duplex). Absolute range -7V to +12V, ±16kV IEC 61000-4-2 ESD protected. Receiver input impedance ≥96kΩ (1/8 unit load).
8	VCC	power_in	Positive supply, 3.15V ≤ VCC ≤ 3.45V (nominal 3.3V). Bypass to GND with a 0.1µF ceramic capacitor placed close to the pin.

Key specifications

Parameter	Value
Manufacturer	HGSEMI
Package	SOP-8
Category	Interface
Pins	8

CAD (KiCad official)

Symbol: MAX3078EM
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOP-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`max3078em.step`	122 KB	You want the bare part, or you mark your own boards.
`max3078em-etched.step`	1.9 MB	You want the part with `MAX3078EM` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 471 faces against 147 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: HGSEMI datasheet (17 pp, sha256 28c5129bb8242502, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
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