Overview
The STCS1PUR, produced by STMicroelectronics, is a BiCMOS constant current source designed to provide a precise constant current from a varying input voltage source. This component is aimed at replacing discrete component solutions for driving LEDs in low voltage applications, such as 5 V, 12 V, or 24 V, offering benefits in terms of precision, integration, and reliability.
The STCS1PUR is particularly useful in industrial and small appliance LED lighting, where it can supply LEDs with a constant current despite variations in the input voltage. It features a shutdown pin, PWM dimming capability, and an open-drain pin for load disconnection diagnostics.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Input Voltage Range | 4.5 to 40 | V |
| Output Current Range | 1 to 1500 | mA |
| Voltage Overhead | < 0.5 | V |
| Feedback Voltage (VFB) | 90 to 110 | mV |
| Quiescent Current (ICC) | 450 to 750 | µA |
| Dropout Voltage (VDROP) | 0.12 to 0.9 | V |
| Operating Temperature Range | -40 to 125 | °C |
| Thermal Resistance Junction-Ambient (RthJA) | 37.6 (DFN8), 45 (PowerSO-8) | °C/W |
| Package | DFN8 (3x3 mm) | |
| RoHS Compliance Grade | Ecopack2 |
Key Features
- Up to 40 V input voltage and up to 1.5 A output current
- Less than 0.5 V voltage overhead
- PWM dimming pin for adjustable brightness control
- Shutdown pin for power management
- LED disconnection diagnostic with open-drain output
- High precision current setting with external resistor (± 10% precision)
- Thermal protection with shutdown at 155 °C and 25 °C hysteresis
Applications
- Supplying LEDs with constant current for varying input voltages
- Low voltage lighting applications (e.g., 5 V, 12 V, 24 V)
- Small appliance LED lighting
- Industrial lighting solutions
Q & A
- What is the maximum input voltage for the STCS1PUR?
The maximum input voltage for the STCS1PUR is 40 V.
- What is the maximum output current of the STCS1PUR?
The maximum output current of the STCS1PUR is 1.5 A.
- How is the current set in the STCS1PUR?
The current is set with an external sensing resistor connected to the FB pin, with a feedback voltage of 100 mV.
- Does the STCS1PUR support PWM dimming?
- What is the purpose of the shutdown pin on the STCS1PUR?
The shutdown pin allows for power management by turning the device on or off.
- How does the STCS1PUR detect LED disconnection?
The STCS1PUR detects LED disconnection through an open-drain output pin (DISC) that pulls low if the LED string is disconnected or fails.
- What is the operating temperature range of the STCS1PUR?
The operating temperature range of the STCS1PUR is -40 °C to 125 °C.
- What is the thermal resistance junction-ambient (RthJA) for the DFN8 package?
The thermal resistance junction-ambient (RthJA) for the DFN8 package is 37.6 °C/W.
- Is the STCS1PUR RoHS compliant?
- What type of package is available for the STCS1PUR?
The STCS1PUR is available in a DFN8 (3x3 mm) package.
