RS-485 transceiver that modulates the data onto an FSK carrier, so the differential signal can share a wire pair that also carries DC power or an existing bus, and a simple capacitor couples it on and off. That lets a network run data and power over the same two wires, cutting cabling in building and industrial systems. An external resistor at F_SET sets the carrier frequency, and MODE selects operation. It behaves like a standard RS-485 transceiver on the logic side (D, R).

Pinout

Pin	Name	Type	Function
1	R	output	Receive data output. CMOS digital output that recovers demodulated data from the RS-485 bus (OOK-demodulated). VOH ≥ VCC−0.4 V @ IOH = −4 mA; VOL ≤ 0.4 V @ IOL = 4 mA. High-Z when MODE = high (transmit mode).
2	MODE	input	Transmit/receive mode selection digital input. Low = receive mode; High = transmit mode. Internal 2-MΩ pull-down to GND (defaults to receive if left floating).
3	F_SET	input	Carrier frequency selection analog input. Connect a resistor RF_SET (1.5 kΩ to 80 kΩ) from this pin to GND to set the OOK carrier frequency f0 (125 kHz to 5 MHz). Recommended load capacitance ≤ 100 pF.
4	D	input	Driver data input. CMOS logic input carrying the transmit data that will be OOK-modulated onto the A/B bus. Internal 2-MΩ pull-up to VCC. VIH ≥ 2 V, VIL ≤ 0.8 V.
5	GND	power_in	Device ground reference for supply, logic, and bus circuits.
6	A	bidirectional	RS-485 differential bus I/O port A (complementary to B). Operational common-mode range −7 V to 12 V; withstands ±18-V DC fault and ±16-kV HBM ESD. Driver short-circuit current limited to ±250 mA.
7	B	bidirectional	RS-485 differential bus I/O port B (complementary to A). Operational common-mode range −7 V to 12 V; withstands ±18-V DC fault and ±16-kV HBM ESD. Driver short-circuit current limited to ±250 mA.
8	VCC	power_in	Device supply, 3.0 V to 5.5 V (nominal 3.3 V to 5 V). Absolute maximum 7 V. Decouple with a local ceramic capacitor near the pin.

Key specifications

Parameter	Value
Type	RS-485 transceiver with FSK modulation
Feature	Data over DC power / shared pair (capacitive coupling)
Carrier	Set by F_SET resistor
Logic side	Driver (D) + receiver (R)
Mode	MODE pin
Supply	3.0-5.5 V
Package	SOT-23-8

Ordering variants

Same part, different packaging or reel option.

THVD8000DDFR (SOT-23-8)
THVD8010DDFR (higher data rate)

CAD (KiCad official)

Symbol: Interface_UART:THVD8000 (KiCad official)
Footprint: Package_TO_SOT_SMD:SOT-23-8
3D model: SOT-23-8 (KiCad packages3D, STEP)

Provenance

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

Datasheet: Texas Instruments datasheet (28 pp, sha256 2c65cc099691c62c, 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