XL0840-AP STMicroelectronics SCR (Other) In Stock
The XL0840-AP is a sensitive-gate SCR from STMicroelectronics rated at 400 V and 800 mA, housed in a TO-92-3 through-hole package. It features a low DC gate trigger current of 0.2 mA max and gate trigger voltage of 0.8 V max. Ideal for phase control and switching applications requiring compact, reliable thyristor solutions.
- Manufacturer
- STMicroelectronics
- Package
- Other
- Pin Count
- 3
- Lifecycle
- OBSOLETE
- Datasheet
- XL0840-AP Datasheet PDF
- Category
- SCR
- Temp Range
- -40.0°C to 125.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of XL0840-AP?
- Sensitive gate triggering with DC gate trigger current as low as 0.2 mA max, enabling direct interface with low-power logic circuits
- Rated at 400 V off-state voltage with 800 mA RMS on-state current and 8 A non-repetitive peak on-state current surge capability
- Compact TO-92-3 through-hole package with single SCR configuration for space-constrained PCB designs
- Minimum critical rate-of-rise of off-state voltage (dV/dt) of 75 V/µs ensuring stable operation in noisy switching environments
What is XL0840-AP used for?
The XL0840-AP sensitive-gate SCR is well-suited for AC power control circuits such as light dimmers, motor speed controllers, and heating element regulators where low gate trigger current is essential. Its compact TO-92-3 package and 400 V blocking voltage make it suitable for line-voltage switching and phase control in home appliances and industrial equipment. It is also used in overvoltage protection circuits and latching relay replacement designs requiring a thyristor with reliable triggering from microcontroller outputs.
What are the specifications of XL0840-AP?
| YTEOL | 0 |
| Configuration | SINGLE |
| Critical Rate of Rise of Off-State Voltage-Min | 75V/us |
| DC Gate Trigger Current-Max | 0.2mA |
| DC Gate Trigger Voltage-Max | 0.8V |
| Holding Current-Max | 5mA |
| JEDEC-95 Code | TO-92 |
| JESD-30 Code | O-PBCY-T3 |
| Non-Repetitive Pk On-state Cur | 8A |
| Number of Elements | 1 |
| On-state Current-Max | 500A |
| Package Body Material | PLASTIC/EPOXY |
| Package Shape | ROUND |
| Package Style | CYLINDRICAL |
| RMS On-state Current-Max | 0.8A |
| Repetitive Peak Off-state Leakage Current-Max | 0.1 µA |
| Repetitive Peak Off-state Voltage | 400V |
| Surface Mount | NO |
| Terminal Form | THROUGH-HOLE |
| Terminal Position | BOTTOM |
| Trigger Device Type | SCR |
| Package | Other |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8541.30.00.80 |
| Country of Origin | Mainland China |
Where can I find the XL0840-AP datasheet?
XL0840-AP Datasheet DownloadOfficial datasheet from STMicroelectronics
What are equivalent replacements for XL0840-AP?
Compatible alternatives and drop-in replacements for XL0840-AP:
STMicroelectronics Silicon Controlled Rectifier, 0.8A I(T)RMS, 0.5mA I(T), 400V V(DRM), 1 Element, TO-92
STMicroelectronics Silicon Controlled Rectifier, 0.8A I(T)RMS, 0.5mA I(T), 400V V(DRM), 1 Element, TO-92
Frequently Asked Questions
What is the minimum gate trigger current required to turn on the XL0840-AP?
The XL0840-AP requires a maximum DC gate trigger current of 0.2 mA and a maximum gate trigger voltage of 0.8 V, making it compatible with low-power logic outputs. This sensitive-gate characteristic allows direct drive from microcontrollers without additional driver circuitry in many designs.
Can the XL0840-AP handle inrush current from capacitive loads during power-up?
The XL0840-AP supports a non-repetitive peak on-state current of 8 A, which provides margin for brief inrush events. Its steady-state on-state RMS current rating is 800 mA at the TO-92-3 package thermal limits, so sustained currents must be kept within that bound.
Which phase-control applications benefit most from the XL0840-AP's 75 V/µs dV/dt rating?
Applications such as AC light dimmers and motor speed controllers operating at 50–60 Hz line frequency benefit from the 75 V/µs minimum critical rate-of-rise of off-state voltage. This rating ensures the SCR will not accidentally trigger due to rapidly rising voltage transients on the 400 V-rated anode circuit.
How does the XL0840-AP's holding current spec affect circuit design?
The XL0840-AP has a maximum holding current of 5 mA, meaning the anode current must remain above 5 mA to keep the device latched on. Circuit designers must ensure the minimum load current exceeds 5 mA during the conduction interval, particularly in resistive-load phase-control designs at low conduction angles.
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About STMicroelectronics
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