1 Features
1• Highest Signaling Rate: 1 Mbps
• Low Power Consumption, Typical I CC per Channel
(3.3-V Operation): 1.5 mA
• Low Propagation Delay – 9 ns Typical
• Low Skew – 300 ps Typical
• Wide T J Range: –55°C to 136°C
• 50-kV/μs Transient Immunity, Typical
• Over 25-Year Isolation Integrity at Rated Voltage
• Operates From 3.3-V and 5-V Supply and Logic
Levels
• 3.3-V and 5-V Level Translation
• Narrow Body SOIC-8 Package
• Safety and Regulatory Approvals:
– 4242 V PK Isolation per DIN V VDE V 0884-10
and DIN EN 61010-1
– 2500 VRMS Isolation for 1 minute per UL 1577
– CSA Component Acceptance Notice 5A, IEC
60950-1 and IEC 61010-1 Standards
– CQC Certification per GB4943.1-2011

2 Applications
• Optocoupler Replacement in:
– Industrial Fieldbus
– Profibus
– Modbus
– DeviceNet™ Data Buses
– Servo Control Interface
– Motor Control
– Power Supplies
– Battery Packs

3 Description
The ISO7421-EP device provides galvanic isolation
up to 2500 VRMS for 1 minute per UL. The ISO7421-
EP device has two isolated channels. Each isolation
channel has a logic input and output buffer separated
by a silicon dioxide (SiO2) insulation barrier. Used in
conjunction with isolated power supplies, the device
prevents noise currents on a data bus or other circuit
from entering the local ground and interfering with or
damaging sensitive circuitry.
This device have TTL input thresholds and require
two supply voltages, 3.3 or 5 V, or any combination.
All inputs are 5-V tolerant when supplied from a 3.3-V
supply.
The ISO7421-EP device is specified for signaling
rates up to 1 Mbps. Due to its fast response time,
under most cases, this device will also transmit data
with much shorter pulse widths. Designers should
add external filtering to remove spurious signals with
input pulse duration <20 ns if desired.