Diodes Incorporated PAM2846KR

Overview

PAM2846KR from Diodes Incorporated is a 6-string, current-mode boost-type LED driver IC with integrated 2.5A MOSFET, ±1% typical string current matching, adjustable switching frequency (500kHz/1MHz/1.6MHz), and 4.8V–28V input range-designed for large LCD panel backlighting requiring uniform brightness across parallel LED strings.

For engineers reviewing the PAM2846KR datasheet, PAM2846KR pinout, PAM2846KR application, or PAM2846KR equivalent, key selection criteria include its six independent constant-current sinks, self-adaptive V_OUT for variable LED string count, open/short LED protection architecture, and QFN4×4-24 package thermal performance (θ_JA = 30°C/W).

Technical Context

The PAM2846KR implements a current-mode boost converter with six dedicated current-sink outputs, each capable of driving up to 40V total string voltage. Its internal 2.5A power MOSFET and low 400mV feedback reference enable high-efficiency operation across wide input and output voltage ranges.

Protection logic includes per-string overvoltage clamping via external resistor divider on OVP pin, short-circuit detection using V_LED monitoring, and thermal shutdown at 150°C with 30°C hysteresis. Dimming is supported via analog (I_SET-based), PWM (PWMD pin), or single-wire ENA pulse modulation methods.

Key Specifications

Pinout & Package

Package: 24-pin QFN (4mm × 4mm, 0.5mm pitch), exposed thermal pad, Pb-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-string LED driver applications.

Compared with AL8862Q-7 and LM3409QMH/NOPB, the PAM2846KR delivers native 6-string integration, tighter current matching, and lower system-level component count-making it optimal for high-reliability, space-constrained LCD backlight designs where uniformity and thermal management are critical.

Availability

PAM2846KR is available at Aetrix Electronics and suitable for LCD TV backlighting, avionics display panels, and industrial HMI displays requiring stable component supply, long-term lifecycle support, and automotive-grade reliability validation.

Supply support for PAM2846KR 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 lighting solutions for industrial, consumer, and automotive markets.

The PAM2846KR belongs to Diodes' LED backlight driver product line, engineered specifically for high-brightness, multi-string LCD panel illumination with emphasis on current accuracy, fault resilience, and thermal robustness in compact form factors.

FAQ

What is the maximum number of LEDs per string the PAM2846KR can drive?

The PAM2846KR supports up to 10 or more LEDs per string, provided the total string forward voltage remains below 40V. With typical white LEDs at ~3.2V, this allows ≥12 LEDs in series per channel. The device's self-adaptive V_OUT automatically adjusts to match the actual string voltage, avoiding unnecessary headroom loss.

How does the PAM2846KR handle an open LED fault in one string?

When an LED opens in any string, the corresponding current sink enters high-impedance state. The device limits output voltage using either the externally configured OVP threshold or a default clamp at 5V + V_f × N_MIN, whichever is lower-preventing overvoltage stress on remaining strings while maintaining partial backlight functionality.

Can the PAM2846KR be used with RGB LED arrays?

Yes-the six independent current sinks support separate red, green, and blue strings (e.g., two strings per color). Each channel's current is individually set via I_SET, and synchronized PWM dimming on PWMD ensures consistent color point across brightness levels without chromaticity shift.

What is the purpose of the three SW pins (22–24) in the QFN package?

The three paralleled SW pins reduce effective bond wire and package inductance, lowering switching losses and improving thermal dissipation. This configuration supports the internal 2.5A MOSFET's continuous operation at full load while minimizing voltage spikes and EMI generation in high-frequency (up to 1.6MHz) boost operation.