Microchip Technology MSL3164BT-R

Overview

MSL3164BT-R from Microchip Technology (formerly Atmel) is a 16-string white/RGB LED driver IC with adaptive DC-DC power control, on-chip EEPROM, and 20 MHz SPI serial interface. It sinks up to 100 mA peak per string with ±3% current accuracy and matching, supports 12-bit per-string PWM dimming at 240 Hz, and enables real-time area dimming for LCD TV backlight systems.

For engineers reviewing the MSL3164BT-R datasheet, MSL3164BT-R pinout, MSL3164BT-R application, or MSL3164BT-R equivalent, this page delivers verified technical context, validated pin functions, confirmed fault monitoring capabilities (open/short circuit, sync loss, overtemperature), and precise SPI timing specs - all critical for backlight architecture design, thermal layout, and multi-device synchronization in high-dynamic-range displays.

Technical Context

The MSL3164BT-R implements Adaptive SourcePower technology to dynamically adjust external LED string supply voltages via three FBOn/FBIn efficiency optimizer channels, minimizing power dissipation while maintaining regulation across varying LED forward voltage distributions. Its internal 20 MHz SPI interface supports daisy-chained configurations of up to 16 devices per bus with chip-select arbitration.

It integrates a 12-bit per-string PWM engine synchronized to external VSYNC (PHI) and HSYNC (GSC) inputs, enabling frame-aligned dimming and programmable per-string phase delay to suppress motion blur artifacts. Global intensity (8-bit) and individual string current (8-bit ISTR + 12-bit PWM) are independently configurable through register writes.

Key Specifications

Pinout & Package

MSL3164BT-R is housed in a 40-pin, 6 mm × 6 mm × 0.75 mm TQFN package with 0.5 mm pitch and thermally enhanced exposed pad (EP). The package supports high-current LED sink paths and efficient heat dissipation via EP-to-ground connection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-channel LED driver applications.

Compared with TLC6983RTQR and IS31FL3733-QFLS4, the MSL3164BT-R uniquely combines video-synchronized PWM, adaptive supply voltage control, and integrated fault reporting - making it the only option among the three qualified for high-end LCD TV and medical display backlighting where dynamic range, power efficiency, and artifact suppression are mandatory.

Availability

MSL3164BT-R is available at Aetrix Electronics and suitable for television backlighting, medical imaging displays, automotive infotainment systems, and architectural signage requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for MSL3164BT-R 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

Microchip Technology acquired Atmel in 2016 and maintains full product support, documentation, and manufacturing continuity for the MSL3163/MSL3164 family.

The MSL3164BT-R belongs to Microchip's high-efficiency LED backlight driver product line, engineered specifically for LCD TVs, medical monitors, and automotive displays demanding adaptive power control, video-sync dimming, and robust fault resilience.

FAQ

What is the maximum number of MSL3164BT-R devices that can be daisy-chained on a single SPI bus?

The MSL3164BT-R supports up to 16 devices per SPI bus using chip-select (CSB) arbitration. Each device is assigned a unique address via AD0/AD1 pins, allowing independent register access and broadcast configuration. This scalability enables control of up to 2560 white LEDs (16 devices × 16 strings × 10 LEDs) in large-format displays without additional controllers. The MSL3164BT-R's 20 MHz SPI interface ensures low-latency updates across the entire chain.

Does the MSL3164BT-R support both white and RGB LED strings?

Yes, the MSL3164BT-R supports both white and RGB LED strings. Its 16 current-sink outputs (STR0–STR15) are electrically identical and rated for 40 V maximum voltage and 100 mA peak current, accommodating typical white LED forward voltages (3.0–3.8 V × 10 = 30–38 V) and RGB configurations (e.g., red: ~2.2 V, green/blue: ~3.2–3.4 V). The datasheet explicitly identifies it as a "16-string White & RGB LED Driver", and its per-string 12-bit PWM and global current control provide independent brightness tuning essential for RGB color mixing.

How does the MSL3164BT-R achieve adaptive power control without external microcontrollers?

The MSL3164BT-R achieves adaptive power control autonomously using its integrated Efficiency Optimizer circuitry - three FBOn outputs (FBO1–FBO3) that inject programmable current (0–255 µA) into the feedback nodes of external DC-DC converters. By monitoring LED string voltage headroom and coordinating with other MSL3164BT-R devices in a chain, it dynamically lowers the supply voltage to the minimum required for regulation - all without host CPU intervention. This hardware-based optimization is enabled by default at power-up and runs continuously, reducing system power dissipation by up to 35%.

What fault conditions does the MSL3164BT-R detect, and how is fault reporting implemented?

The MSL3164BT-R detects open-circuit and short-circuit faults on each STR0–STR15 output, loss of PHI or GSC video synchronization, and overtemperature conditions. Fault status is reported via an active-low open-drain FLTB pin and detailed register maps (FLTSTATUS, OCSTAT0/1, SCSTAT0/1). Individual string fault reporting can be enabled/disabled per channel using FLTMASK registers. Clearing FLTB requires either toggling the EN pin low-then-high or reading the fault status registers - ensuring reliable system-level error handling without false triggers.

Can the MSL3164BT-R operate without an external video timing source?

Yes, the MSL3164BT-R can operate without an external video timing source. When PHI and GSC inputs are left unconnected or configured as inactive, the device uses its internal 18.15–21.88 MHz oscillator (set via OSCCTRL register) to generate PWM timing. The base PWM frequency remains 240 Hz, and global/intensity control remains fully functional. However, frame-aligned dimming, per-string phase adjustment, and motion blur reduction require PHI/GSC synchronization - so standalone operation supports basic brightness control but not advanced LCD artifact suppression.