Diodes Incorporated PAM2841GR

Overview

PAM2841GR from Diodes Incorporated is a 1.5A switch-current, 40V precision white LED driver IC in U-DFN2020-8 (Type A) package, operating from 2.7V–5.5V input and delivering up to 40V output for driving ≥10 series WLEDs. It integrates fixed 1MHz switching frequency, analog/PWM dimming support, overvoltage/overcurrent/thermal/UVLO protection, and achieves peak efficiency of 90% in portable backlighting systems.

For engineers reviewing the PAM2841GR datasheet, PAM2841GR pinout, PAM2841GR application, or PAM2841GR equivalent, key selection criteria include its 1.5A SW current limit, 200mV feedback voltage tolerance, 40V OVP threshold, soft-start-enabled ENA pin, and dual-package availability (MSOP-8/U-DFN2020-8) for space-constrained designs.

Technical Context

The PAM2841GR implements a current-mode boost converter architecture with internal 1.5A MOSFET switch and precision 200mV ±3mV feedback reference. Its control loop uses compensation via the Comp pin to stabilize output current across varying LED forward voltages and temperature.

Four dimming methods are supported: ENA-pin PWM (100–200Hz), Comp-pin PWM via external nMOS (100–500Hz), analog DC voltage injection at FB node, and filtered PWM as DC-equivalent control - all enabling precise brightness regulation without altering LED color point.

Key Specifications

Pinout & Package

U-DFN2020-8 (Type A) package: 2.0mm × 2.0mm × 0.6mm body, exposed thermal pad, NiPdAu-plated terminals, MSL Level 1, 0.007g weight.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AL8862SP-13 and RT9397BZSP, the PAM2841GR provides superior thermal performance (80°C/W vs. 120–150°C/W), tighter current regulation (±1.5% vs. ±3–5%), and independent OVP configuration - making it optimal for high-reliability, space-limited portable displays.

Availability

PAM2841GR is available at Aetrix Electronics and suitable for smartphone backlighting, tablet display drivers, automotive infotainment systems, and portable medical monitors requiring stable component supply and long-term production continuity.

Supply support for PAM2841GR 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in power management, signal integrity, and connectivity solutions for consumer, industrial, and automotive markets.

The PAM2841 belongs to Diodes' precision LED driver product line, engineered specifically for high-efficiency, low-profile backlighting in battery-powered portable displays with stringent thermal and EMI constraints.

FAQ

What dimming methods does the PAM2841GR support, and which is best for flicker-free operation?

The PAM2841GR supports four dimming methods: ENA-pin PWM (100–200Hz), Comp-pin PWM (100–500Hz), analog DC voltage injection at FB, and filtered PWM. For flicker-free operation, analog dimming is optimal - it avoids PWM-related temporal artifacts entirely and maintains constant current without modulation, preserving color consistency and eliminating visible strobing even at low brightness levels.

How does the OVP pin function, and what resistor values are needed for 36V output protection?

The OVP pin triggers shutdown when voltage exceeds 1.2V. To protect a 36V output, use a resistor divider where R1 (top) and R2 (bottom) satisfy V_OVP = V_OUT × R2/(R1+R2) = 1.2V. For example, R2 = 100kΩ and R1 = 2.9MΩ yields 1.2V at 36V. The divider must draw <1µA to avoid loading the OVP comparator and maintain accuracy.

Can the PAM2841GR drive more than 10 WLEDs, and what limits the maximum string count?

Yes - the PAM2841GR can drive >10 WLEDs depending on forward voltage. With 40V max output and typical 3.0–3.6V per LED, up to 13 LEDs (3.1V × 13 = 40.3V) are feasible. The hard limit is the 40V OVP threshold; exceeding this risks shutdown. Thermal limits (T_J ≤ 150°C) and inductor saturation also constrain sustained operation at high string counts.

What layout practices are critical for stable operation at 1MHz switching frequency?

Three layout practices are essential: (1) Minimize SW-node loop area - keep inductor, Schottky diode, and output capacitor traces short and wide; (2) Separate PGND (power ground) and SGND (signal ground), connecting them at a single point near the input capacitor; (3) Place 1µF input ceramic capacitor within 2mm of VIN and PGND pins, and route FB/OVP traces away from noisy SW and inductor paths to prevent regulation error.