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

Broadcom Limited ASSR-401C-503E

Name: ASSR-401C-503E
Brand: Broadcom Limited
SKU: ASSR-401C-503E
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: ASSR-401C-503E

Manufacturer:: Broadcom Limited

Category:: Solid State Relays (SSR)

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

Datasheet:: ASSR-401C-503E.pdf

Description:: SSR RELAY SPST-NO 40MA 0-400V

Quantity:: RFQ Add To RFQ list

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Inventory:3,002

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Product details

Overview

ASSR-401C-503E from Broadcom (formerly Avago) is a surface-mount, single-channel, normally-off solid-state relay in SO-4 package, featuring 400V output withstand voltage, 0.04A current rating, 65Ω typical on-resistance, 0.3nA off-state leakage, and 0.08ms turn-on time - deployed in automated test equipment for high-reliability signal switching.

For engineers reviewing the ASSR-401C-503E datasheet, pinout, applications, or equivalent options, key selection criteria include input LED drive compatibility (1mA min), output isolation integrity (3750 Vrms), low C×R (650 pF·Ω), and RoHS-compliant tape-and-reel delivery for SMT production.

Technical Context

The ASSR-401C-503E integrates an AlGaAs infrared LED optically coupled to a photovoltaic diode array and MOSFET driver stage, enabling galvanic isolation and bi-directional AC/DC switching. It operates with 1mA minimum input current and turns off at ≤0.8V forward voltage across the LED.

Its internal architecture delivers 3750 Vrms input-output isolation per UL1577, 4.9mm minimum creepage/clearance, and 175V comparative tracking index (CTI), meeting safety requirements for Class II insulation in measurement systems.

Key Specifications

Parameter	Value and Actual Design Meaning
Output Withstand Voltage	400 V - supports safe switching of signals up to ±400V without breakdown
On-Resistance (R_ON)	65 Ω typical - ensures minimal voltage drop and power loss at 40mA load
Off-State Leakage	0.3 nA typical - preserves signal integrity in high-impedance measurement paths
Turn-On Time (t_ON)	0.08 ms typical - enables sub-millisecond channel switching in multiplexed data acquisition
Input-Output Isolation	3750 Vrms - meets UL1577 and CSA Component Acceptance for reinforced insulation
C × R Product	650 pF·Ω typical - minimizes transient coupling and improves system settling time
Operating Temperature	−40°C to +85°C - validated for industrial-grade embedded instrumentation environments

Pinout & Package

ASSR-401C-503E uses a 4-pin SOIC surface-mount package (SO-4), 3.56 mm body width, 1.27 mm lead pitch, RoHS-compliant lead-free finish, and tape-and-reel packaging (1500 units/reel).

Pin/Terminal	Circuit Role	Design Meaning
Pin 1	Anode (LED input)	Positive terminal for driving infrared LED; requires ≥1mA forward current to activate relay
Pin 2	Cathode (LED input)	Ground return path for LED; logic-low (<0.8V) disables output conduction
Pin 3	Source (MOSFET output)	One side of bi-directional output switch; connects to load return or reference node
Pin 4	Drain (MOSFET output)	Other side of bi-directional output switch; handles ±400V, 40mA bidirectional current

Key Features

Feature	Design Value
Bi-directional Output Switching	Enables AC and DC signal routing without polarity constraints in multiplexer or ATE front-ends
Low Input Drive Requirement	1mA LED current suffices for full turn-on - compatible with microcontroller GPIOs without buffer stages
High Transient Immunity	≥1 kV/μs dV/dt rejection - suppresses false triggering from EMI in noisy test environments
Ultra-Low Off-State Leakage	0.3 nA max at 400V - critical for precision voltage/current measurements where leakage induces offset errors
RoHS-Compliant Packaging	Lead-free SO-4 with tape-and-reel (−503E suffix) - supports automated SMT assembly and environmental compliance

Applications

Automatic Test Equipment (ATE)	Data Acquisition Systems
Use Scenario: High-speed channel selection in semiconductor wafer testers requiring >10k cycles/hour reliability. IC Role / Device Role / Timing Role: Solid-state SPST relay replacing electromechanical relays for signal path routing. Use Value: 0.08ms t_ON and 0.05ms t_OFF enable faster test sequencing than EMRs; 0.3nA leakage avoids measurement drift.	Use Scenario: Multiplexing analog sensor inputs (thermocouples, strain gauges) into a shared ADC channel. IC Role / Device Role / Timing Role: Isolated, low-leakage analog switch providing channel-to-channel isolation and signal integrity. Use Value: 400V withstand and 3750 Vrms isolation protect ADC front-end from high-voltage transients during sensor fault conditions.
Dataloggers & Recorders	EMR / Reed Relay Replacement
Use Scenario: Long-term field deployment logging voltage/current waveforms across multiple industrial nodes. IC Role / Device Role / Timing Role: Bi-directional, low-power signal switch enabling battery-operated channel scanning. Use Value: 1mA LED drive and 160 mW output power dissipation allow extended operation without thermal derating.	Use Scenario: Upgrading legacy reed relay-based PCBs to eliminate mechanical wear, contact bounce, and coil drive complexity. IC Role / Device Role / Timing Role: Drop-in replacement for Form A SPST reed relays in 4-pin SO footprint. Use Value: Same SO-4 footprint and pinout as mechanical equivalents; no layout change required for retrofit designs.

Automatic Test Equipment (ATE)

Data Acquisition Systems

Use Scenario: High-speed channel selection in semiconductor wafer testers requiring >10k cycles/hour reliability.

IC Role / Device Role / Timing Role: Solid-state SPST relay replacing electromechanical relays for signal path routing.

Use Value: 0.08ms t_ON and 0.05ms t_OFF enable faster test sequencing than EMRs; 0.3nA leakage avoids measurement drift.

Use Scenario: Multiplexing analog sensor inputs (thermocouples, strain gauges) into a shared ADC channel.

IC Role / Device Role / Timing Role: Isolated, low-leakage analog switch providing channel-to-channel isolation and signal integrity.

Use Value: 400V withstand and 3750 Vrms isolation protect ADC front-end from high-voltage transients during sensor fault conditions.

Dataloggers & Recorders

EMR / Reed Relay Replacement

Use Scenario: Long-term field deployment logging voltage/current waveforms across multiple industrial nodes.

IC Role / Device Role / Timing Role: Bi-directional, low-power signal switch enabling battery-operated channel scanning.

Use Value: 1mA LED drive and 160 mW output power dissipation allow extended operation without thermal derating.

Use Scenario: Upgrading legacy reed relay-based PCBs to eliminate mechanical wear, contact bounce, and coil drive complexity.

IC Role / Device Role / Timing Role: Drop-in replacement for Form A SPST reed relays in 4-pin SO footprint.

Use Value: Same SO-4 footprint and pinout as mechanical equivalents; no layout change required for retrofit designs.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
TLP3554(F)	Higher 600V output withstand; 0.15A rating; 1.2V typical LED forward voltage	Better suited for higher-voltage industrial control; requires higher drive current	Select when >400V isolation or >40mA load capability is needed; not pin-compatible
PS8501-AX	Lower 250V output withstand; 0.02A rating; 0.2nA leakage; 0.1ms t_ON	Optimized for ultra-low-leakage medical instrumentation; reduced voltage margin	Choose for sub-nA leakage-critical biosignal paths where 250V rating is sufficient

Compared with TLP3554(F) and PS8501-AX, the ASSR-401C-503E offers balanced 400V/40mA capability, industry-standard SO-4 footprint, and lowest C×R (650 pF·Ω) - making it optimal for high-throughput ATE and precision DAQ where speed, leakage, and layout compatibility are jointly constrained.

Availability

ASSR-401C-503E is available at Aetrix Electronics and suitable for automatic test equipment, data acquisition systems, and datalogger designs requiring stable component supply, RoHS-compliant SMT packaging, and long-lifecycle availability.

Supply support for ASSR-401C-503E 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. (formerly Avago Technologies) is a global semiconductor leader specializing in optical, wireless, and wired connectivity solutions, with deep heritage in optocouplers and isolation technologies.

The ASSR-401C-503E belongs to the ASSR-40xC series - engineered specifically for fast-switching, low-leakage signal routing in test and measurement systems where electromechanical relay limitations must be overcome.

FAQ

What is the maximum continuous output voltage rating for ASSR-401C-503E?

The ASSR-401C-503E has a rated output withstand voltage of 400 V, verified under DC conditions with VF = 0.8 V and IO = 250 µA at TA = 25°C. This is not a continuous operating voltage but a momentary withstand rating; sustained operation should remain within system-level safety margins defined by IEC/EN 60747-5-2. The ASSR-401C-503E datasheet specifies 360 V minimum at elevated temperature.

Is ASSR-401C-503E pin-compatible with standard 4-pin SOIC electromechanical relays?

Yes - the ASSR-401C-503E uses a standard 4-pin SOIC footprint matching common Form A SPST reed and EMR replacements. Pin 1 (anode) and Pin 2 (cathode) align with LED drive terminals, while Pins 3 and 4 form the isolated bi-directional output switch. No PCB redesign is needed when upgrading from compatible mechanical relays.

What is the minimum input current required to fully turn on ASSR-401C-503E?

The ASSR-401C-503E requires a minimum forward current of 1 mA through the input LED (Pins 1–2) to guarantee reliable turn-on across the full −40°C to +85°C operating range. For stable performance at temperature extremes, Broadcom recommends operating at IF = 5 mA, which also improves t_ON/t_OFF consistency. The ASSR-401C-503E achieves full conduction at this drive level.

Does ASSR-401C-503E support AC signal switching?

Yes - the ASSR-401C-503E features a bi-directional MOSFET output stage capable of switching both AC and DC signals up to ±400 V peak. Its symmetrical structure allows current flow in either direction when the LED is energized, making it suitable for AC-coupled instrumentation paths, audio routing, and universal analog multiplexing where polarity independence is required.

What safety certifications apply to ASSR-401C-503E?

The ASSR-401C-503E is UL Recognized per UL 1577 (3750 Vrms for 1 minute) and approved under CSA Component Acceptance Notice #5. It provides reinforced insulation with 4.9 mm minimum creepage and clearance, CTI of 175 V, and IIIa insulation group classification - qualifying it for use in measurement equipment requiring basic or reinforced isolation per IEC 61010-1.

ASSR-401C-503E Specifications

Product attributes: Attribute value

Manufacturer:: Broadcom Limited

Series:: ASSR

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

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:: 40 mA

On-State Resistance (Max):: 100 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-401C-503E FAQ

1.How can I place an order for ASSR-401C-503E through Aetrix?

Please submit a Request for Quotation (RFQ) for ASSR-401C-503E 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-401C-503E reliable?

The price and inventory of ASSR-401C-503E are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ASSR-401C-503E is usually 5 days.

3.What payment methods are accepted for ASSR-401C-503E?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ASSR-401C-503E transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ASSR-401C-503E?

ASSR-401C-503E orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ASSR-401C-503E 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-401C-503E?

For technical support, including ASSR-401C-503E datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ASSR-401C-503E requirements.

6.How does Aetrix verify that ASSR-401C-503E is sourced from the original manufacturer or authorized distributors?

All ASSR-401C-503E 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-401C-503E meets industry standards.

7.What is the process for return or replacement of ASSR-401C-503E?

All ASSR-401C-503E units undergo pre-shipment inspection (PSI). If there is an issue with ASSR-401C-503E, 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-401C-503E part is unused and in its original packaging.

Return procedure for ASSR-401C-503E:

1.Submit a request within 90 days.

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

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