STMicroelectronics PM6600

Overview

PM6600 from STMicroelectronics is a monolithic 6-row LED driver IC with integrated boost regulator, designed specifically for LCD panel backlighting. It delivers up to 32 mA per row (±2.1% current accuracy, ±2% inter-row matching), supports up to 36 V output voltage (10 WLEDs/row), and features PWM dimming down to 1% duty cycle at 20 kHz. Used in notebook and UMPC displays requiring precise current regulation and fault-aware LED driving.

For engineers reviewing the PM6600 datasheet, PM6600 pinout, PM6600 application, or PM6600 equivalent, key selection considerations include its integrated 36 V boost stage, six independently controllable current sinks, open/short LED fault detection, programmable soft-start, and external synchronization capability for multi-device timing alignment.

Technical Context

The PM6600 integrates a constant-frequency peak current-mode boost controller with an internal 36 V/2 A power MOSFET and a dedicated +5 V LDO (LDO5) for analog supply. Its boost section operates from 4.7 V to 28 V input and supports 200 kHz–1 MHz switching frequency via resistor programming or external sync on FSW/SYNC pins.

The backlight driver comprises six high-accuracy current sinks (ROW1–ROW6), each programmable up to 32 mA via RILIM, with 500 ns minimum dimming pulse width and real-time LED open/short fault detection routed through FAULT and MODE pins. Unused rows are automatically floated without external intervention.

Key Specifications

Pinout & Package

PM6600 is housed in a VFQFPN-24 package (4 mm × 4 mm, exposed thermal pad), optimized for compact LCD backlight designs with high thermal efficiency.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX16820 and TPS61165, the PM6600 uniquely integrates six matched current sinks with boost regulation and comprehensive fault management in a single 4 mm × 4 mm package - delivering higher integration, tighter luminance uniformity, and faster system-level fault response for multi-zone LCD backlights.

Availability

PM6600 is available at Aetrix Electronics and suitable for notebook monitors, UMPC displays, and industrial panel PCs requiring stable component supply, long-term lifecycle support, and automotive-grade reliability under extended temperature operation.

Supply support for PM6600 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 PM6600 belongs to ST's LED backlight driver product line, engineered specifically for high-efficiency, fault-aware LCD panel illumination in space-constrained portable and medical display systems.

FAQ

What is the maximum number of white LEDs the PM6600 can drive per row?

The PM6600 supports up to 10 white LEDs per row, enabled by its 36 V boost output voltage and 32 mA per-row current capability. This assumes typical forward voltage of 3.2–3.6 V per white LED at 20–30 mA, resulting in a total string voltage of ~32–36 V - within the device's specified output range and protected by programmable OVP.

How does the PM6600 handle an open LED fault in one row?

When an open LED fault occurs in any ROW (e.g., ROW3), the PM6600 disables that specific current sink, asserts the open-drain FAULT pin low, and continues normal operation on remaining functional rows. The MODE pin configures fault response behavior, and the device reports the condition without latching - allowing host firmware to log, retry, or initiate safe shutdown.

Can the PM6600 synchronize switching frequency across multiple devices?

Yes - the FSW pin accepts external clock input, and the SYNC pin outputs a synchronized clock signal. Connecting SYNC of one PM6600 to FSW of another enables precise phase-aligned operation across up to four devices, minimizing input ripple and EMI in multi-backlight systems such as dual-display laptops or large-format panels.

What thermal performance can be expected in a standard 4-layer PCB layout?

In a typical 4-layer board with 2 oz copper, 10 cm² exposed thermal pad copper pour, and moderate airflow, the PM6600 achieves ≤65°C junction rise at full load (6 × 32 mA, VIN = 12 V). Its RthJA is 42°C/W, and thermal shutdown activates at 125°C junction - providing robust margin for continuous operation in sealed notebook chassis.