STMicroelectronics STP16CL596XTTR

Overview

STP16CL596XTTR from STMicroelectronics is a 16-channel constant-current LED sink driver in TSSOP-24 exposed-pad package, designed for serially controlled LED panel displays. It operates from 3.0–3.6V supply, delivers 15–90mA per channel with ±3% current matching, supports 25MHz clock input, and features daisy-chainable SDO output synchronized to falling clock edge.

For engineers reviewing the STP16CL596XTTR datasheet, STP16CL596XTTR pinout, STP16CL596XTTR application, or STP16CL596XTTR equivalent, key selection criteria include output current adjustability via R_EXT, thermal performance of the exposed-pad TSSOP, propagation delays under 280ns, and compatibility with 3.3V microcontrollers in high-density LED signage systems.

Technical Context

The device integrates a 16-bit serial-in/parallel-out shift register cascaded with a 16-bit D-type storage latch, enabling precise timing control of LED on/off states. Output enable (OE) is active-low and provides global blanking, while latch enable (LE) controls data transfer from shift register to output latches independently of clock activity.

Each of the 16 output channels uses an internally regulated current source referenced to an external R_EXT resistor, delivering matched sink current across all outputs with ≤±4% inter-channel error at 20mA. The SDO output changes state on the falling edge of CLK, minimizing skew-induced timing errors in multi-device daisy chains.

Key Specifications

Pinout & Package

TSSOP-24 with exposed thermal pad (electrically unconnected); requires PCB thermal pad connection for rated power dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED sink driver applications.

Compared with TB62706CFNG and IS31FL3728-QFLS4, the STP16CL596XTTR uniquely combines 25MHz serial speed, 16V output compliance, and exposed-pad thermal performance-making it optimal for high-brightness, high-refresh LED panels where timing integrity and thermal headroom are critical.

Availability

STP16CL596XTTR is available at Aetrix Electronics and suitable for indoor LED video walls, automotive interior lighting control, industrial HMI status displays, and architectural LED strip controllers requiring stable component supply and long-term manufacturability.

Supply support for STP16CL596XTTR 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, specializing in power management, analog, MEMS, and microcontroller technologies for industrial, automotive, and consumer markets.

The STP16CL596 belongs to ST's LED driver product line, engineered specifically for high-reliability, constant-current serial sink applications in large-format LED displays and lighting systems demanding precision current matching and thermal robustness.

FAQ

What is the function of the exposed thermal pad on the STP16CL596XTTR package?

The exposed pad is a thermally conductive metal surface on the underside of the TSSOP-24EP package, electrically isolated but designed to be soldered to a PCB copper pour. It reduces thermal resistance from junction to ambient by 2.5× versus standard TSSOP, enabling sustained 90mA/channel operation at +85°C ambient temperature without derating.

How does the STP16CL596XTTR achieve current matching across all 16 output channels?

Current matching is achieved through laser-trimmed on-die current sources referenced to a common R_EXT terminal. At 20mA output, inter-channel error is guaranteed ≤±4%, and between-device variation is ±10%. This matching is process-stable across temperature and supply voltage, eliminating need for per-channel external resistors.

Can the STP16CL596XTTR drive LEDs directly from a 3.3V microcontroller GPIO without level shifting?

Yes. All digital inputs (SDI, CLK, LE, OE) meet 3.3V CMOS thresholds: VIH ≥ 0.7×VDD (2.31V) and VIL ≤ 0.3×VDD (0.99V). With VDD = 3.3V, the device accepts direct connection to STM32, ESP32, or PIC32 GPIOs, provided series resistors ≤100Ω are used for ESD protection on SDI/CLK lines.

What is the purpose of the R-EXT pin, and how is output current calculated?

R-EXT sets the reference current for all 16 channels using the formula I_OUT ≈ 12.5V / R_EXT. For example, a 470Ω resistor yields ~26.6mA per channel. The relationship is linear and temperature-compensated; typical accuracy is ±3% between channels and ±10% between devices, verified across -40°C to +125°C operating range.