STMicroelectronics STCS2SPR

Overview

STCS2SPR from STMicroelectronics is a BiCMOS constant-current LED driver IC designed for low-voltage LED lighting systems. It delivers up to 2 A output current with ±10% accuracy, less than 0.5 V dropout voltage, and operates from 4.5 V to 40 V input. Its integrated N-MOSFET, PWM dimming pin, shutdown control, and open-drain LED disconnection diagnostic make it suitable for automotive interior lighting and 12 V/24 V appliance LED modules.

For engineers reviewing the STCS2SPR datasheet, STCS2SPR pinout, STCS2SPR application, or STCS2SPR equivalent, key selection criteria include its 100 mV feedback reference, thermal shutdown at 155 °C, PowerSO-10 package thermal resistance (12 °C/W with heatsink), and compatibility with discrete resistor-based current setting across 1 mA–2 A range.

Technical Context

The STCS2SPR integrates a high-voltage preregulator (45 V rating) and precision 100 mV bandgap-referenced current-sense amplifier to regulate LED current via external FB-resistor feedback. Its internal N-MOSFET features a SOURCE pin referenced to 100 mV, enabling low-loss current sensing with minimal overhead.

Control logic includes independent EN (shutdown) and PWM inputs with sub-µs timing response (TD = 3 µs rise, 1.2 µs fall), while DISC provides open-drain fault reporting triggered by VDRAIN < 75 mV - indicating LED string open-circuit conditions without requiring external comparators.

Key Specifications

Pinout & Package

STCS2SPR is housed in a PowerSO-10 surface-mount package with exposed thermal pad (internally connected to GND), optimized for high-current thermal dissipation on FR4 PCBs. Recommended layout uses copper-filled vias and ≥6 cm² heatsink area to achieve R_thJA = 12 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with AL8862SP-13 and LM3407MMX/NOPB, STCS2SPR offers superior integration (integrated 2 A MOSFET, 100 mV reference, DISC diagnostic) and simpler layout for ≤5 W, low-differential-voltage LED systems - making it optimal for cost-sensitive, thermally relaxed 12 V/24 V lighting where simplicity and reliability outweigh peak efficiency needs.

Availability

STCS2SPR is available at Aetrix Electronics and suitable for automotive interior lighting, 12 V appliance LED modules, and low-voltage architectural lighting requiring stable component supply and long-term industrial availability.

Supply support for STCS2SPR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The STCS2 product line targets cost-effective, highly integrated LED drivers for low-voltage constant-current applications - specifically replacing discrete transistor-resistor solutions in 5–24 V systems where precision, reliability, and board-space savings are critical.

FAQ

What is the minimum input voltage required for STCS2SPR to regulate 2 A LED current?

The STCS2SPR requires a minimum input voltage of 4.5 V to operate. To sustain 2 A output, the input must exceed the sum of LED forward voltage plus dropout voltage (0.58 V typical). For example, with three 3.6 V white LEDs (10.8 V total VF), minimum VIN = 10.8 V + 0.58 V = 11.38 V - well within its 4.5–40 V range.

How does the DISC pin detect LED disconnection?

The DISC pin monitors V_DRAIN relative to GND. When EN is high and V_DRAIN falls below 75 mV (indicating no current flow due to open LED string), the internal comparator pulls DISC low (≤0.5 V at 5 mA sink). This occurs independently of PWM state and requires no external components.

Can STCS2SPR drive multiple parallel LED strings?

No - STCS2SPR is designed for single-string constant-current operation. Driving parallel strings causes current imbalance due to V_F mismatch, risking thermal runaway. For multi-string applications, one STCS2SPR per string or a switching topology with individual current regulation is required.

What PCB layout practices maximize thermal performance in PowerSO-10?

Maximize thermal performance by connecting the exposed thermal pad directly to a ≥6 cm² copper pour using ≥16 copper-filled vias (0.7 mm diameter, 1.8 mm pitch). Avoid thermal relief on pad connections, and ensure the pour is solid (no splits) and tied to GND. This achieves R_thJA ≈ 12 °C/W, enabling full 2 A operation at 50 °C ambient.