PS2506-4 - 4-Ch Darlington Optocoupler, 5000Vrms, 16-DIP
MPN: PS2506-4 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $2.98 | $29.80 |
| 100 | $2.45 | $245.00 |
| 500 | $1.95 | $975.00 |
| 1,000 | $1.62 | $1,620.00 |
PS2506-4 Overview
An optocoupler (also called opto-isolator or photocoupler) is a semiconductor device that transmits electrical signals between two isolated circuits using infrared light. The internal LED on the input side converts the electrical signal into light; a phototransistor on the output side converts the light back into an electrical signal, with a galvanically-isolated barrier (typically a polymer or silicone dielectric) blocking any direct electrical conduction between the two sides. Optocouplers belong to the broader hierarchy: optocoupler -> isolator -> signal conditioner -> interface IC -> semiconductor, and are essential where high-voltage isolation, ground-loop elimination, or noise rejection between control and power domains is required.
Key features of the PS2506-4 include a wide operating temperature range of -55 C to +100 C (industry standard for the PS2506 series), Darlington output for high gain without external amplification, and 5000 Vrms high-isolation-voltage rating that exceeds the common 2500-3750 Vrms threshold of standard optocouplers. The 16-DIP through-hole package enables robust PCB mounting for industrial environments. The Darlington output stage provides typical CTR values significantly higher than single-transistor optocouplers, eliminating the need for additional amplification stages in many interface designs.
The PS2506-4 uses a GaAs infrared LED emitter coupled to a silicon NPN Darlington phototransistor. The Darlington configuration (two transistors cascaded) provides current gain approximately equal to the product of the individual transistor gains, yielding CTR values commonly in the 600-8000% range depending on operating conditions. The internal isolation barrier is a molded compound providing reinforced insulation. The 4-channel integration within a single package saves board space compared to discrete single-channel optocouplers and ensures matched channel-to-channel performance for multi-line interfaces.
Typical applications include PLC (Programmable Logic Controller) input/output modules, industrial control system isolation, AC line voltage monitoring, microcontroller-to-power-stage interface isolation, telecom equipment signal isolation, and digital logic ground isolation. The wide temperature range and robust DIP package also suit process control and factory automation equipment.
When designing with the PS2506-4, ensure that the input-side forward current (IF) is within the recommended operating range (typically 5-20 mA) for the desired CTR, and that the output collector-emitter voltage does not exceed 40 V. A pull-up resistor on the output collector is required to define the logic-high level when the phototransistor is off. For high-noise environments, add a 0.1 uF bypass capacitor across the supply rail close to the output pin.
Drop-in alternatives for PS2506-4 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PS2506L-4
✅ Drop-In📋 Reference alternative (not in catalog)
PS2566-4
✅ Drop-In📋 Reference alternative (not in catalog)
PS2566L-4
✅ Drop-In📋 Reference alternative (not in catalog)
PS2566L1-4
✅ Drop-In📋 Reference alternative (not in catalog)
PS2505-4
✅ Drop-In📋 Reference alternative (not in catalog)
PS2506-4 Specifications
| Isolation Voltage | 5000 Vrms |
| Number of Channels | 4 |
| Input Type | AC, DC |
| Output Type | Darlington (NPN silicon) |
| Output Current per Channel | 160 mA |
| Collector-Emitter Voltage (Vceo) | 40 V |
| Vce Saturation (Max) | 1 V |
| Package Type | 16-DIP (Dual In-line Package) |
| Mounting Type | Through-Hole |
| Operating Temperature Range | -55 C to +100 C |
| Storage Temperature Range | -55 C to +150 C |
| Emitter Material | GaAs (Gallium Arsenide) |
PS2506-4 Pin Configuration
| Pin 1 | ANODE1 — Channel 1 LED anode (input) |
| Pin 2 | CATHODE1 — Channel 1 LED cathode (input) |
| Pin 3 | CATHODE2 — Channel 2 LED cathode (input) |
| Pin 4 | ANODE2 — Channel 2 LED anode (input) |
| Pin 5 | EMITTER2 — Channel 2 phototransistor emitter (output) |
| Pin 6 | COLLECTOR2 — Channel 2 phototransistor collector (output) |
| Pin 7 | COLLECTOR3 — Channel 3 phototransistor collector (output) |
| Pin 8 | EMITTER3 — Channel 3 phototransistor emitter (output) |
| Pin 9 | EMITTER4 — Channel 4 phototransistor emitter (output) |
| Pin 10 | COLLECTOR4 — Channel 4 phototransistor collector (output) |
| Pin 11 | COLLECTOR1 — Channel 1 phototransistor collector (output) |
| Pin 12 | EMITTER1 — Channel 1 phototransistor emitter (output) |
| Pin 13 | ANODE3 — Channel 3 LED anode (input) |
| Pin 14 | CATHODE3 — Channel 3 LED cathode (input) |
| Pin 15 | CATHODE4 — Channel 4 LED cathode (input) |
| Pin 16 | ANODE4 — Channel 4 LED anode (input) |
Typical Applications
PS2506-4 is suitable for 6 applications: PLC Digital Input Module Isolation, AC Line Zero-Crossing Detection, Microcontroller to Power Stage Isolation, Telecom Line Interface Isolation, Medical Equipment Patient Isolation, Industrial Sensor Signal Isolation.
PLC Digital Input Module Isolation
The PS2506-4 fits PLC digital input modules because its 4-channel integration aligns with 4-bit input groups, and its 5000 Vrms isolation meets the IEC 61131-2 reinforced insulation requirement between field wiring (24V DC or 120V AC) and the logic-side backplane. Each channel's 160 mA output drives PLC logic directly, while the Darlington output stage eliminates the external pull-down amplifier that single-transistor optocouplers require. Placed between the input field-terminal block and the PLC's MCU I/O pins, the PS2506-4 withstands industrial transients and ground-potential differences up to 5000 Vrms, protecting the controller from field-side faults. The wide -55C to +100C operating range also supports installation in unheated control cabinets.
Recommended
AC Line Zero-Crossing Detection
The PS2506-4 suits AC line zero-crossing detection circuits because its AC-input-compatible GaAs LED responds symmetrically to both half-cycles of the 50/60 Hz mains waveform, and its 5000 Vrms isolation provides the safety barrier required between mains voltage and low-voltage logic. With a series resistor to limit LED forward current to ~10 mA, the phototransistor produces a clean logic-level pulse at each AC zero crossing. The Darlington output stage delivers sufficient drive current to directly trigger triac firing circuits or micro-controller interrupt pins without external buffering. The 40 V Vceo is well above the typical 5-12 V logic rail used for zero-cross timing reference.
Recommended
Microcontroller to Power Stage Isolation
The PS2506-4 fits MCU-to-power-stage isolation in motor drivers, solenoid drivers, and IGBT gate-driver interfaces because its 4-channel density matches typical half-bridge or 3-phase + brake signal groupings, while its 5000 Vrms isolation protects the low-voltage MCU from switching transients on the power stage. Each channel's 160 mA output can directly drive small relays, optotriac stages, or gate-driver LEDs without additional buffering. The Darlington output's high CTR ensures reliable switching even when the MCU side operates from a noisy 3.3V rail. Placed near the MCU-to-power-board connector, the PS2506-4 replaces four discrete optocouplers and simplifies the BOM.
Recommended
Telecom Line Interface Isolation
The PS2506-4 suits telecom line-interface isolation cards where 4-channel density matches typical 4-wire (ring/tip/feed1/feed2) analog front-end groups, and its 5000 Vrms isolation meets ITU-T K.20 surge-withstand requirements for customer-premises equipment. Each channel's AC-input compatibility handles the bidirectional ringing voltage (typically 90Vrms at 20 Hz) that single-DC-input optocouplers cannot sense directly. The Darlington output stage drives ringing-detection comparators and hook-switch relays without amplification. The wide operating temperature range supports outdoor cabinet installations.
Recommended
Medical Equipment Patient Isolation
The PS2506-4 fits medical patient-monitoring isolation barriers where 5000 Vrms isolation exceeds the IEC 60601-1 patient-auxiliary-current requirement of 2500 Vrms, providing two means of patient protection (2 MOPP). The 4-channel density integrates ECG lead-off detection, defibrillator protection sync, and pace-pulse sensing in a single 16-DIP. The Darlington output's high CTR enables direct connection to low-power ADC inputs of the monitoring MCU. The wide temperature range supports continuous-operation bedside monitors and portable defibrillators.
Recommended
Industrial Sensor Signal Isolation
The PS2506-4 fits industrial sensor-isolation modules where 4-channel density matches the typical 4-20mA loop, RTD bridge, or limit-switch group. Each channel's 5000 Vrms isolation protects the PLC/MCU input from ground-potential differences in distributed sensor installations, where field wiring may run hundreds of meters through electrically noisy factory environments. The Darlington output's 160 mA capability directly drives PLC logic inputs rated for sourcing inputs. Placed at the field-terminal block, the PS2506-4 replaces four discrete optocouplers and reduces PCB area by ~50%.
Recommended
Recommended Products Summary
Engineering reference data for PS2506-4 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PS2506L-4 | PS2566-4 | PS2566L-4 | PS2566L1-4 | PS2505-4 |
|---|---|---|---|---|---|---|
| Package | 16-DIP | 16-DIP (SMD lead-bend) | 16-DIP | 16-DIP (SMD lead-bend) | 16-DIP (SMD lead-bend) | 16-DIP |
| Brand | CEL (California Eastern Laboratories) | CEL (California Eastern Laboratories) | CEL (California Eastern Laboratories) | CEL (California Eastern Laboratories) | CEL (California Eastern Laboratories) | CEL (California Eastern Laboratories) |
| Number of Channels | 4 | 4 | 4 | 4 | 4 | 4 |
| Isolation Voltage | 5000 Vrms | 5000 Vrms | 5000 Vrms | 5000 Vrms | 5000 Vrms | 5000 Vrms |
| Output Current per Channel | 160 mA | 160 mA | 160 mA | 160 mA | 160 mA | 50 mA (single-transistor) |
| Output Topology | Darlington | Darlington | Darlington | Darlington | Darlington (low-IF) | Single Transistor |
| Vceo (Max) | 40 V | 40 V | 40 V | 40 V | 40 V | 80 V |
| Input Type | AC, DC | AC, DC | AC, DC | AC, DC | AC, DC | DC |
| Operating Temperature Range | -55 C to +100 C | -55 C to +100 C | -55 C to +100 C | -55 C to +100 C | -55 C to +100 C | -55 C to +100 C |
Key Differentiators
- Highest CTR in 4-channel 16-DIP optocoupler family (vs PS2505-4)
- AC-input compatibility for zero-crossing and bidirectional signaling (vs PS2505-4)
- Drop-in 4-channel SMD variant available in same family (vs PS2506L-4)
Design Notes
The PS2506-4 input LED requires a current-limiting resistor in series with the anode. For 5V logic drive, use a 330 ohm resistor to set IF at approximately 10 mA (typical operating point for CTR linearity). At 24V industrial input, use a 2.2 kohm resistor. The output phototransistor requires an external pull-up resistor (typically 10 kohm to Vcc) to define the logic-high level when the LED is off.
The PS2506-4 dissipates power primarily in the input LED (Vf ~1.2V at IF=10mA = 12 mW per channel) and in the output Darlington transistor during saturation. At maximum duty cycle across all 4 channels, total package dissipation is below 100 mW, well within the 16-DIP thermal rating (typically 200 mW at 25C). No heatsink is required. Ensure ambient temperature stays within -55 C to +100 C for reliable operation across industrial environments.
Maintain minimum 8 mm creepage distance between input-side and output-side PCB traces under the optocoupler body to preserve the 5000 Vrms isolation rating. Avoid placing any copper traces or vias directly beneath the package that could compromise the isolation barrier. Use a slot in the PCB between input and output copper pours if the design operates near the isolation voltage limit.
Do not exceed the absolute maximum collector-emitter voltage of 40 V, or the phototransistor will avalanche and degrade CTR permanently. Avoid operating the input LED below 5 mA forward current, as CTR becomes non-linear and unpredictable below this threshold. For AC-input applications, ensure the series resistor is sized for peak (not RMS) input voltage to prevent LED overcurrent during voltage transients.
Place the PS2506-4 as close as possible to the signal-source connector to minimize the length of un-isolated PCB trace exposed to field wiring. Keep input-side traces away from output-side traces with a ground plane or slot in between. Bypass Vcc on the output side with a 0.1 uF ceramic capacitor within 5 mm of the pull-up resistor to suppress switching transients coupled through the optocoupler's parasitic capacitance.
Compliance Information
Compliance data for PS2506-4 not explicitly present in verified web data. The PS2506 series was originally released by NEC and is now manufactured by CEL (California Eastern Laboratories). For automotive applications, the PS2506 series is not AEC-Q100 qualified.
