STMicroelectronics LED1202JR

Overview

LED1202JR from STMicroelectronics is a 12-channel low-quiescent-current LED driver in WLCSP20 (1.71 × 2.16 mm, 0.4 mm pitch) package, delivering up to 20 mA per channel with 350 mV typical headroom voltage at 16 mA, 1% typical current matching, and dual 8-bit analog + 12-bit PWM dimming control. It enables breathing effects and synchronized multi-device RGB lighting in wearable electronics and battery-powered accessories.

For engineers reviewing the LED1202JR datasheet, LED1202JR pinout, LED1202JR application, or LED1202JR equivalent, key selection criteria include I²C address configurability (8 local + 1 global), open-LED detection threshold (100 mV), phase-shift timing (≈380 µs between channels), and thermal shutdown at 150 °C - all critical for reliable low-noise, multi-LED system design.

Technical Context

The LED1202JR integrates twelve independent low-side current sinks with per-channel analog dimming (8-bit, 1–20 mA range) and local 12-bit PWM control (220 Hz base frequency, 1/4095 duty-step resolution). Its dual-current-sink architecture switches at ~3.76 mA to maintain <2% current matching down to 2.5 mA while minimizing ground noise.

It supports autonomous pattern sequencing via eight internal volatile registers, with programmable duration (22.2–5660 ms per pattern), repetition count (1–254 or infinite), and synchronization across multiple devices using shared clock domain (A0 clock-out / A1 clock-in) or global I²C address (0x5C) for simultaneous enable.

Key Specifications

Pinout & Package

LED1202JR is packaged in WLCSP20 (1.71 × 2.16 × 0.5 mm, 0.4 mm ball pitch), optimized for space-constrained wearable PCBs. Ball assignment follows JEDEC-standard top-view marking side layout.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-channel LED driver applications.

Compared with TLC59284RGER and IS31FL3731-QFLS4-TR, LED1202JR uniquely combines ultra-compact WLCSP20 packaging, autonomous pattern execution, and dual analog+PWM dimming - making it optimal for space- and power-constrained wearable lighting where reliability and animation autonomy are mandatory.

Availability

LED1202JR is available at Aetrix Electronics and suitable for wearable electronics, battery-powered devices, and portable accessories requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for LED1202JR 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 specializing in power management, analog, and microcontroller solutions for industrial, automotive, and consumer markets.

The LED1202JR belongs to ST's precision LED driver product line, engineered specifically for ultra-low-power, high-accuracy RGB lighting in miniaturized portable electronics - emphasizing quiescent current minimization, autonomous operation, and robust fault handling.

FAQ

What is the minimum headroom voltage required for full 20 mA output on LED1202JR?

The typical headroom voltage is 350 mV at 16 mA output, but it increases nonlinearly below ~3.76 mA due to dual-current-sink architecture. At 20 mA, V_{CS_MIN} is 420 mV (max, per datasheet Figure 4 extrapolation), meaning VIN must be ≥2.42 V for a 2.0 V LED string. This ensures stable regulation without dropout across process/voltage/temperature corners.

How does the phase-shift feature reduce inrush current in multi-LED systems?

Phase shifting delays activation of each of the 12 CSx outputs by ≈380 µs, spreading the total turn-on current over 4.16 ms instead of instantaneous. Measured data shows this lowers peak input current by 83% versus simultaneous switching - allowing use of smaller input capacitors (e.g., 2.2 µF instead of 10 µF) and reducing PCB area and cost.

Can LED1202JR operate with a 1.8 V I²C bus while powered from 2.6 V?

Yes. The I²C interface is explicitly rated for 1.8 V logic compatibility (VIH = 1.26 V, VIL = 0.54 V), and SCL/SDA pins tolerate up to 6 V. With VIN = 2.6 V, internal level-shifting circuitry ensures reliable communication even when host MCU I/Os run at 1.8 V - no external translators are needed.

What happens to pattern sequencing during an open-LED fault?

Open-LED detection asserts IRQn but does not halt pattern execution. The faulty channel (e.g., CS3) remains OFF, while remaining 11 channels continue their programmed sequence uninterrupted. The "Open LED" status register (0x07–0x08) latches the fault until read, enabling firmware to log and recover without disrupting UI animation flow.