ISO6721
Public Unreviewedby Ray
TI dual-channel digital isolator, SOIC-8. One forward + one reverse channel, 3 kVrms, up to 100 Mbps, low power. Datasheet-verified.
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markdownISO6721
Texas Instruments · Digital isolator · SOIC-8
Passes two logic signals across a galvanic barrier, one in each direction, with each side on its own supply and ground. The silicon-dioxide capacitive barrier isolates them while data crosses at up to 100 Mbps, and its low per-channel current makes it a power-frugal choice for isolated SPI, UART, and control links. The narrow SOIC-8 is rated 3 kVrms. Built on the same isolation core as the ISO67xx family, it is a smaller, lower-power alternative to the ISO7721.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VCC1 | power_in | Side-1 power supply, 1.71 V to 5.5 V referenced to GND1. |
| 2 | OUTA | output | Isolated push-pull digital output for channel A (driven by INA on side 2), CMOS/LVCMOS levels referenced to VCC1/GND1. |
| 3 | INB | input | Digital input for channel B, CMOS/LVCMOS levels referenced to VCC1/GND1. |
| 4 | GND1 | power_in | Ground return for VCC1 (side 1). |
| 5 | GND2 | power_in | Ground return for VCC2 (side 2). |
| 6 | OUTB | output | Isolated push-pull digital output for channel B (driven by INB on side 1), CMOS/LVCMOS levels referenced to VCC2/GND2. |
| 7 | INA | input | Digital input for channel A, CMOS/LVCMOS levels referenced to VCC2/GND2. |
| 8 | VCC2 | power_in | Side-2 power supply, 1.71 V to 5.5 V referenced to GND2. |
Key specifications
| Parameter | Value |
|---|---|
| Type | Dual-channel digital isolator (1 forward + 1 reverse) |
| Isolation | 3000 Vrms (SOIC-8) |
| Data rate | Up to 100 Mbps |
| CMTI | 100 kV/us (typ) |
| Supply (each side) | 1.71-5.5 V |
| Default output | High or low (part suffix) |
| Package | SOIC-8 |
Ordering variants
Same part, different packaging or reel option.
ISO6721BDR (SOIC-8, default-high)ISO6721DR (basic isolation)ISO6721FDR (default-low)
CAD (KiCad official)
- Symbol:
Isolator:ISO6721BD (KiCad official) - Footprint:
Package_SO:SOIC-8_3.9x4.9mm_P1.27mm - 3D model: SOIC-8 (KiCad packages3D, STEP)
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Texas Instruments datasheet (48 pp, sha256
b4ed1e5c2b8d5587, 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).