Si8751/52 Data Sheet

Isolated FET Driver with Pin Control or Diode Emulator Inputs

The Si875x enables new pathways to the creation of custom Solid State Relay (SSR)

configurations. The Si875x integrates robust isolation technology with an SSR FET driver. A

floating secondary side dc power supply is unnecessary as the product generates its own

self-contained gate drive output voltage. When combined with a customer-selected external

FET, a complete Solid State Relay is formed, allowing customers to optimize their system

for cost, PCB area, power, On-Resistance, and thermal performance.

Customers have a choice of digital input control (Si8751) or diode emulation control

(Si8752) to best suit their application. The Si875x integrates versatile outputs that support

driving AC or DC load configurations.

The Si875x eliminates the need for bulky mechanical relays which can be difficult to assem-

ble onto PCBs and add switching noise to the system.

Traditional SSRs integrate optocoupler-style LED inputs, which limit the operating tempera-

ture range of the solution. The Si875x experiences no such limitation and can support full

industrial and automotive temperature ranges with increased stability and longer life.

The Si875x drives FET gates with a nominal 10 V using as little as 1 mA input current.

Increasing the input current to 10 mA enables turn-on times as fast as 94 μs. Input side

voltages on the Si8751 are flexible from 2.25 V to 5.5 V supporting seamless connection

to low-power controllers. The Si875x devices provide an Active Miller Clamp to prevent the

unintended turn-on of the external FET when a high dV/dt is present on the FET’s drain.

The Si875x is qualified to the AEC-Q100 standard, making it suitable for automotive applica-

tions. Further, its 2.5 KVrms isolation rating forms the basis for full certification to UL, CSA,

VDE, and CQC.

Applications include mechanical relay, photo switch, or SSR replacement in motor control,

valve control, HVAC relay, automotive, charging, battery monitoring, ac mains line switching,

and more.

The Si8751 and Si8752 come in ROHS-compliant SOIC-8 packaging, providing a compact,

industry-standard footprint and generous margin to creepage and clearance requirements.

KEY FEATURES

• Drives user-selected external FETs

• Choice of digital input control (Si8751)

or diode emulation control (Si8752)

• Internally generated secondary side

power supply

• 10 V output with 1 mA input current

• As fast as 82 μs turn-on time and 46

us turn-off time

• Active Miller Clamp to prevent

unintended turn-on and reduce

inductive chatter

• Supports AC or DC load switching

• 2.5 KVrms isolation rating

• UL, CSA, VDE, and CQC certifications

• AEC-Q100 qualified

• Industrial –40 to 105 °C or Automotive

–40 to 125 °C temperature ranges

• ROHS-compliant SOIC-8 Package

APPLICATIONS

• Motor Controls

• Valve Controls

• HVAC Relays

• HEV/EV Automotive Charging

• Battery Monitoring

• AC Mains Line Switching

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

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206331A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • July 27, 2022

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