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Home > Products > Relays > Solid State Relays (SSR)

Broadcom Limited ASSR-4118-003E

Name: ASSR-4118-003E
Brand: Broadcom Limited
SKU: ASSR-4118-003E
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: ASSR-4118-003E

Manufacturer:: Broadcom Limited

Category:: Solid State Relays (SSR)

Package:: 4-SOP (0.173", 4.40mm)

Datasheet:: ASSR-4118-003E.pdf

Description:: SSR RELAY SPST-NO 100MA 0-400V

Quantity:: RFQ Add To RFQ list

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Inventory:2,709

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Product details

Overview

ASSR-4118-003E from Broadcom is a single-channel, normally-off, solid-state photo-MOSFET relay in a 4-pin SO package, featuring 400 V output withstand voltage, 0.1 A DC current rating, 25 Ω typical on-resistance (AC/DC), and 3 mA minimum LED turn-on current. It replaces electromechanical relays in telecom switching, industrial controls, and medical isolation circuits where low EMI, long life, and high reliability are required.

For engineers reviewing the ASSR-4118-003E datasheet, pinout, applications, or equivalent options, key selection criteria include input-output insulation (3750 VRMS), output leakage (<1 μA), turn-on/off timing (0.7 ms / 0.04 ms typ), and SO-4 surface-mount compatibility for space-constrained PCBs.

Technical Context

The ASSR-4118-003E integrates an AlGaAs infrared LED optically coupled to a photovoltaic diode array and dual-MOSFET driver circuit, enabling galvanic isolation without external bias. Its Form A SPST configuration operates as a bidirectional signal switch with no moving parts, requiring only 3 mA input current to close the output contact and ≤0.8 V to open it.

It delivers 3750 VRMS input-to-output isolation per UL1577, supports AC/DC output loads up to 400 V, and maintains <1 μA output leakage at rated voltage. The SO-4 package ensures compact mounting while meeting creepage/clearance requirements of ≥4.9 mm between input and output terminals.

Key Specifications

Parameter	Value and Actual Design Meaning
Output Withstand Voltage	400 V - Maximum continuous voltage the output can block without breakdown; defines safe operating range for AC/DC load switching.
On-Resistance (R_ON)	25 Ω typical - Determines I²R power loss and voltage drop across closed output; impacts thermal design at 0.1 A load.
Input Turn-On Current	3 mA min - Minimum LED forward current needed to reliably activate the MOSFET output; enables direct CMOS/TTL drive.
Isolation Voltage (V_ISO)	3750 V_RMS - Dielectric strength rating for 1 minute; certifies safety compliance per UL1577 and CSA Component Acceptance #5.
Turn-On/Off Time	0.7 ms / 0.04 ms typ - Enables fast digital control response; critical for pulse-width modulated or high-cycle-count switching applications.
Output Leakage Current	≤1 μA at 400 V - Ensures minimal off-state power loss and signal integrity in high-impedance sensing or battery-powered circuits.
Operating Temperature	–40°C to +85°C - Specifies ambient range for reliable operation without derating; validated for industrial and medical environments.

Pinout & Package

ASSR-4118-003E uses a 4-pin Small Outline (SO-4) surface-mount package with gull-wing leads, RoHS compliant and lead-free. Dimensions: 4.40 × 2.00 × 1.78 mm (L × W × H), 2.54 mm lead pitch.

Pin/Terminal	Circuit Role	Design Meaning
Pin 1	LED Anode	Positive input terminal for infrared LED; requires series resistor to limit current to 3–20 mA.
Pin 2	LED Cathode	Ground return path for LED; connects to system ground or logic low to enable conduction.
Pin 3	Output Source	One side of the MOSFET output switch; connects to load return or common reference point.
Pin 4	Output Drain	Switched output terminal; carries load current when relay is ON; bidirectional for AC/DC use.

Key Features

Feature	Design Value
Compact solid-state SPST relay	Replaces electromechanical relays in space-constrained designs without sacrificing isolation or lifetime.
400 V output withstand voltage	Supports direct switching of telecom line voltages, industrial sensors, and medical equipment signals.
Low 3 mA input activation threshold	Enables direct interface with microcontrollers and logic ICs without additional driver stages.
3750 V_RMS input-output isolation	Meets safety-critical requirements for patient-connected medical devices and industrial control systems.
0.04 ms typical turn-off time	Reduces switching transients and improves timing precision in high-speed data acquisition and test equipment.

Applications

Telecom Line Switching	Industrial PLC I/O Isolation
Use Scenario: Routing analog voice signals or DSL line pairs in carrier-grade access equipment. IC Role / Device Role / Timing Role: Solid-state SPST relay providing galvanic isolation between subscriber lines and central office circuitry. Use Value: Eliminates mechanical wear and contact bounce, ensuring >10⁹ operations and stable impedance matching over temperature.	Use Scenario: Isolating 24 V DC sensor inputs and 120/240 V AC actuator outputs in programmable logic controllers. IC Role / Device Role / Timing Role: Input/output channel isolator with Form A SPST functionality and 400 V blocking capability. Use Value: Prevents ground loops and noise coupling while supporting fast scan cycles via sub-millisecond switching.
Medical Patient Monitoring	Security System Zone Control
Use Scenario: Isolating ECG electrode leads and defibrillation-safe signal paths in bedside monitors. IC Role / Device Role / Timing Role: Safety-rated signal switch enabling patient-connected circuit separation per IEC 60601-1. Use Value: Delivers 3750 V_RMS isolation and <1 μA leakage-critical for low-power, high-impedance biopotential measurements.	Use Scenario: Controlling alarm siren zones, door lock actuators, and motion detector outputs in commercial security panels. IC Role / Device Role / Timing Role: Low-power, long-life relay replacement for zone enable/disable functions with AC/DC flexibility. Use Value: Supports both 12 V DC locks and 24 V AC sirens using same footprint; eliminates coil burnout and contact corrosion.

Telecom Line Switching

Industrial PLC I/O Isolation

Use Scenario: Routing analog voice signals or DSL line pairs in carrier-grade access equipment.

IC Role / Device Role / Timing Role: Solid-state SPST relay providing galvanic isolation between subscriber lines and central office circuitry.

Use Value: Eliminates mechanical wear and contact bounce, ensuring >10⁹ operations and stable impedance matching over temperature.

Use Scenario: Isolating 24 V DC sensor inputs and 120/240 V AC actuator outputs in programmable logic controllers.

IC Role / Device Role / Timing Role: Input/output channel isolator with Form A SPST functionality and 400 V blocking capability.

Use Value: Prevents ground loops and noise coupling while supporting fast scan cycles via sub-millisecond switching.

Medical Patient Monitoring

Security System Zone Control

Use Scenario: Isolating ECG electrode leads and defibrillation-safe signal paths in bedside monitors.

IC Role / Device Role / Timing Role: Safety-rated signal switch enabling patient-connected circuit separation per IEC 60601-1.

Use Value: Delivers 3750 V_RMS isolation and <1 μA leakage-critical for low-power, high-impedance biopotential measurements.

Use Scenario: Controlling alarm siren zones, door lock actuators, and motion detector outputs in commercial security panels.

IC Role / Device Role / Timing Role: Low-power, long-life relay replacement for zone enable/disable functions with AC/DC flexibility.

Use Value: Supports both 12 V DC locks and 24 V AC sirens using same footprint; eliminates coil burnout and contact corrosion.

Equivalent & Alternatives

The following parts are listed as comparable options for similar solid-state relay applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
Toshiba TLP3548A	SO-6 package, 600 V output rating, 0.12 A current, 1.2 V typical LED forward voltage.	Higher voltage rating suits industrial motor control; larger package requires layout change.	Choose for >400 V AC line switching where higher standoff is mandatory.
Vishay VO3120	DIP-6 package, 400 V rating, 0.1 A, 1.15 V VF, but lacks UL1577 recognition (only IEC 60747-5-2).	Requires additional safety validation for medical or UL-marked end equipment.	Choose for cost-sensitive industrial controls where full UL recognition is not required.

Compared with TLP3548A and VO3120, the ASSR-4118-003E offers verified UL1577/CSA certification in the smallest SO-4 footprint, optimized for high-reliability telecom and medical applications where regulatory compliance and board space are primary constraints.

Availability

ASSR-4118-003E is available at Aetrix Electronics and suitable for telecom switching, industrial PLC I/O modules, and medical patient monitoring systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for ASSR-4118-003E includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Broadcom Inc. is a global semiconductor leader designing high-performance connectivity, infrastructure, and optoelectronic solutions for enterprise, industrial, and communications markets.

The ASSR-41xx series was developed specifically as solid-state replacements for electromechanical relays in safety-isolated signal routing applications, emphasizing reliability, low drive power, and regulatory-certified insulation.

FAQ

What is the maximum continuous output voltage rating for ASSR-4118-003E?

The ASSR-4118-003E has a maximum continuous output withstand voltage of 400 V. This rating applies to both AC and DC loads and is validated under standard operating conditions (TA = 25°C). Exceeding this voltage may cause irreversible breakdown of the internal MOSFETs. For transient protection, external clamping circuits are recommended per Broadcom Application Note 1074.

Can ASSR-4118-003E switch AC signals, and what is its bidirectional capability?

Yes, ASSR-4118-003E supports bidirectional AC/DC switching due to its symmetrical MOSFET output structure. Pins 3 and 4 form a non-polarized SPST contact capable of conducting current in either direction, making it suitable for analog signal routing, audio switching, and AC load control without polarity concerns.

What is the minimum input current required to reliably turn on ASSR-4118-003E across temperature?

The ASSR-4118-003E requires a minimum LED forward current of 3 mA to guarantee turn-on across its full operating temperature range (–40°C to +85°C). While the device may activate at lower currents (≥0.5 mA), Broadcom recommends 5 mA for robust performance over temperature and lifetime, as confirmed in the Absolute Maximum Ratings table.

Does ASSR-4118-003E require an external gate drive or bias supply for the output MOSFETs?

No, ASSR-4118-003E does not require any external gate drive or bias supply. Its integrated photovoltaic diode array generates sufficient gate voltage to fully enhance the output MOSFETs using only the input LED current. This self-contained architecture simplifies design and eliminates auxiliary power rails.

How is the 3750 V_RMS isolation rating of ASSR-4118-003E verified and certified?

The 3750 V_RMS input-output isolation rating of ASSR-4118-003E is certified per UL 1577 (component recognition program) and CSA Component Acceptance Notice #5. Testing involves applying 3750 V_RMS for 1 minute between shorted input pins (1+2) and shorted output pins (3+4), with leakage current limited to <10 μA. This rating is documented in the Insulation and Safety Related Specifications section of the AV02-0218EN datasheet.

ASSR-4118-003E Specifications

Product attributes: Attribute value

Manufacturer:: Broadcom Limited

Series:: ASSR

Packaging:: Tube

Product Status:: Active

Mounting Type:: Surface Mount

Circuit:: SPST-NO (1 Form A)

Output Type:: AC, DC

Voltage - Input:: 1.3VDC

Voltage - Load:: 0 V ~ 400 V

Load Current:: 100 mA

On-State Resistance (Max):: 35 Ohms

Termination Style:: Gull Wing

Operating Temperature:: -40°C ~ 85°C

Supplier Device Package:: 4-SOP (2.54mm)

Approval Agency:: CSA, UL

Grade:: -

Qualification:: -

ASSR-4118-003E FAQ

1.How can I place an order for ASSR-4118-003E through Aetrix?

Please submit a Request for Quotation (RFQ) for ASSR-4118-003E on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for ASSR-4118-003E reliable?

The price and inventory of ASSR-4118-003E are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ASSR-4118-003E is usually 5 days.

3.What payment methods are accepted for ASSR-4118-003E?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ASSR-4118-003E transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ASSR-4118-003E?

ASSR-4118-003E orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ASSR-4118-003E order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for ASSR-4118-003E?

For technical support, including ASSR-4118-003E datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ASSR-4118-003E requirements.

6.How does Aetrix verify that ASSR-4118-003E is sourced from the original manufacturer or authorized distributors?

All ASSR-4118-003E products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that ASSR-4118-003E meets industry standards.

7.What is the process for return or replacement of ASSR-4118-003E?

All ASSR-4118-003E units undergo pre-shipment inspection (PSI). If there is an issue with ASSR-4118-003E, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The ASSR-4118-003E part is unused and in its original packaging.

Return procedure for ASSR-4118-003E:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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