BOM cost and mounting area can be reduced by integrating 4ch isolation + high side/low side switch! Introducing the "Si834x" series

Isolated smart switch solution for industrial IO - "Si834x" series, Si83401BAA-IF, Si83401BBA-IF, Si83402BAA-IF, Si83404BAA-IF, Si83404AAA-IF, Si83405BDA-IF, Si83406BDA-IF, Si83408BDA-IF, Si83408ADA-IF ,Si83408AFA-IF,Si83408BFA-IF,Si83411BAA-IF,Si83411BBA-IF,Si83412BAA-IF,Si83414BAA-IF,Si83414AAA-IF,Si83415BDA-IF,Si83416BDA-IF,Si83418BDA-IF,Si83418ADA-IF,Si83 418AFA-IF,Si83418BFA -IF,,ContactSkyworksforTheseOptions,Si83401BCA-IF,Si83402BBA-IF,Si83402BCA-IF,Si83404BBA-IF,Si83404ABA-IF,Si83404ACA-IF,Si83404BCA-IF,Si83405BFA-IF,Si83406BFA-IF,Si83411BCA-IF, Si83412BBA-IF, Si83412BCA-IF,Si83414BBA-IF,Si83414ABA-IF,Si83414ACA-IF,Si83414BCA-IF,Si83415BFA-IF,Si83416BFA-IF,

BOM cost and mounting area can be reduced by integrating 4ch isolation + high side/low side switch into one chip!

Introduction of 24V digital IO isolated smart switch IC "Si834x" series for industrial equipment

High Side SW, Low Side SW, high side switch, low side switch

Product Summary

"Si834x" is an isolated smart switch that is ideal for controlling 12 V and 24 V industrial digital IO loads. This is a product that combines digital output circuits and isolation devices such as photocouplers, which were conventionally constructed by combining multiple chips such as discrete protection elements, into a 4-channel single package.
Capable of driving inductive or resistive loads with up to 0.7A continuous current per channel. There is also an option to allow inrush current (8A) for the lamp filament. Since the load impedance is checked and controlled, small and safe control is possible. Equipped with various diagnostic functions, the control interface includes a parallel interface that controls each channel independently, and an SPI interface that allows daisy chain connection of up to 32 devices (128 channels).

The lineup also includes 1.25A/2ch products and 2.5A/1ch products.

Target application

Si834x smart switches are ideal for controlling resistive and inductive loads such as solenoids, relays, and lamps in digital IO used in industrial equipment such as PLCs.

It is a 24V digital output solution that is equipped with various internal protection functions and is protected against overcurrent, overvoltage due to demagnetization (kickback voltage), etc.

Programmable controller (PLC/sequencer) and industrial 12V/24V digital IO
motion controller
Smart Solid State Relay (SSR)

Product features

Sink output/source output compatible product options available
Output current and channel number options: 0.7A/ch 4ch, 1.25A/ch 2ch, 2.5A/1ch 1ch
Option to support high inrush current (8A) such as lamp filament
Various diagnostic functions - power supply monitor, overcurrent, overtemperature, open detection, communication error diagnosis, etc.
Various protection functions - short circuit/overcurrent protection, overtemperature protection
Dielectric strength 1.5kVrms (UL1577 1 min.)
Common mode transient voltage immunity (CMTI) Min. 100kV/us
Parallel/SPI control option (daisy chain possible up to 128ch via SPI)
Compact 9x9mm DFN32 package

Built-in protection functions minimize external components and enable miniaturization.

The device itself is also very small in a small QFN package.

Product lineup

See Si834x datasheet P3 Ordering Guide

Each item in the model number list (Ordering Guide) indicates the following functions.

Si83401BAA-IF,Si83401BBA-IF,Si83402BAA-IF,Si83404BAA-IF,Si83404AAA-IF,Si83405BDA-IF,Si83406BDA-IF,Si83408BDA-IF,Si83408ADA-IF,Si83408AFA-IF,Si83408BFA-IF,Si83411BAA-IF,Si83411BBA-IF,Si83412BAA-IF,Si83414BAA-IF,Si83414AAA-IF,Si83415BDA-IF,Si83416BDA-IF,Si83418BDA-IF,Si83418ADA-IF,Si83418AFA-IF,Si83418BFA-IF,,ContactSkyworksforTheseOptions,Si83401BCA-IF,Si83402BBA-IF,Si83402BCA-IF,Si83404BBA-IF,Si83404ABA-IF,Si83404ACA-IF,Si83404BCA-IF,Si83405BFA-IF,Si83406BFA-IF,Si83411BCA-IF,Si83412BBA-IF,Si83412BCA-IF,Si83414BBA-IF,Si83414ABA-IF,Si83414ACA-IF,Si83414BCA-IF,Si83415BFA-IF,Si83416BFA-IF,

Many option lineups with and without the following functions

・ Ordering part Number	Product No
・ Output Driver Type	High side or low side switch
・ Input Interface	Parallel and SPI and both
・ Output Channels	Number of output channels
・ Continuous Output Current	Steady output current 0.7A (155mΩ), 1.25A (78mΩ), 2.5A (41mΩ)
・ Inrush Current Mode	A mode that allows inrush current from lamps, etc. for a certain period of time.
・ Channel Status Indicator	The status of each channel can be displayed on the control side
・ Low Voltage Indicator	Incorrect power supply voltage display
・ Open Channel indicator	Channel open detection
・ Clear Fault Input	Input to manually reset diagnostic report for Fault pin

Product features

8 diagnostic functions

It has a function that allows you to check the load status and device power supply in an integrated manner.

	Diagnostic function	Severity	Description
per channel	Open-Circuit	Warning	Terminal open detection Normal output
	Over-Current	Shutdown	Detects overload. Turns off the output immediately.
	Over-Temperature	Constraint	Overheat protection for each channel Slows down the demagnetization time and does not turn the output back on
All channels	Over-Temperature	Shutdown	All outputs are turned off when the chip overheats.
	VDD2 Low-Voltage	Warning	VDD2 is lower than VDD2 _UV18. Full output normal
	VDD2 Overvoltage	Constraint	Decrease degaussing speed when VDD2 exceeds VDD2 _OV32.
	VDD2 Undervoltage	Shutdown	All outputs are turned off when VDD2 exceeds VDD2 _UV9.
	VDD1 Undervoltage	Shutdown	All outputs OFF when VDD1 is lower than VDD1 _UV.
	Communication Error	Shutdown	All outputs are turned OFF when the signal between 1st and 2nd order is interrupted.

Constraint: Restriction

Multi-voltage “smart” output clamp

For example, when a relay connected to an output is turned from ON to OFF, a high voltage is generated at the terminal and current flows. This consumes the energy stored in the relay coil and demagnetizes it, which generates heat. In conventional circuits, this energy was consumed by external diodes, etc., which required components with large heat capacity and current capacity.

The multi-voltage degaussing clamp function enables miniaturization of external components.

Conventional product voltage/current waveform

Due to large kickback, heat loss to the device is also large.

Si834x output waveform

The kickback that occurs is clamped at a low voltage and is less likely to turn into heat.

Short protection circuit and inrush current mode

If the output current limit current IOCL is exceeded, the output will turn off after a certain period of time (tOCL), and the circuit has been designed to prevent device destruction.
Instead of continuing to flow current and shutting off due to overtemperature, it is controlled based on the load and is designed to prevent the junction temperature from rising.

Additionally, some options allow inrush current up to 8A (IOPCL), making it possible to drive lamp filaments, etc.*

* Only model numbers that have Inrush Current Mode "Yes" listed on the Si834x datasheet P3 Ordering Guide are supported.