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Texas Instruments ISO7521CDWR — Digital Isolators

ISO7521CDWR Digital Isolator, 4243Vrms, 1 Mbps, 16-SOIC

MPNISO7521CDWR
End of Life

Texas Instruments ISO7521CDWR, General Purpose digital isolator, Capacitive Coupling, 2 Channel, 1/1 Inputs, 4243Vrms isolation, 1Mbps data rate, 14ns propagation delay, 25kV/µs CMTI, -40°C to 105°C, 16-SOIC package.

$3.88Ref. price · indicative, final on quote
Packaging16-SOIC (0.295", 7.50mm Width)
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

ISO7521CDWR specifications
ParameterValue
TypeGeneral Purpose
Channel typeUnidirectional
MountingSurface Mount
Supply voltage3.15V ~ 3.45V, 4.75V ~ 5.25V
Voltage - isolation4243Vrms
Isolated powerNo
Operating temperature-40°C ~ 105°C
Pulse width distortion3.7ns
PackageTape & Reel (TR); Cut Tape (CT)
Data rate1Mbps
TechnologyCapacitive Coupling
Case16-SOIC (0.295\", 7.50mm Width)
Channels2
Inputs - side 1/Side 21/1
Rise (Fall time)1ns, 1ns
Propagation delay tpLH (tpHL)14ns, 14ns
Common mode transient immunity25kV/µs

Product details

4243Vrms isolation — where it fits in the system

The 1 Mbps data rate is adequate for GPIO isolation, slow SPI (up to a few MHz), or UART handshake lines, but it will bottleneck a full-speed CAN or Ethernet interface — keep that in mind when reading the BOM.

Propagation delay and CMTI — the real-world margins

Propagation delay is 14 ns max in both directions, with a pulse-width distortion of 3.7 ns max. That is tight enough for most control-loop isolation where timing skew between channels matters. The common-mode transient immunity of 25 kV/µs is a strong number — it means the output won't glitch when a nearby relay or IGBT switches, which is the failure mode that kills a fieldbus link in a noisy cabinet. Rise and fall times are 1 ns typical, so the signal edges are clean but the layout needs care to avoid ringing on long traces.

Supply rails and temperature range

That means it can translate between a 3.3 V MCU domain and a 5 V sensor or actuator interface without an extra level shifter.

The wide pitch helps with creepage distance on the PCB — important when you are trying to meet 4243Vrms isolation without routing slots under the part.

ROHS3 compliant. For dual-sourcing resilience, the closest functional peer is the ISO7221CDR (same 2-channel unidirectional topology, 25 Mbps data rate, 2500Vrms isolation), but the ISO7221CDR has a lower isolation rating and a narrower supply range — verify the isolation requirement before swapping.

Frequently asked questions

Does ISO7521CDWR support 5V signaling?

Yes.