Analog Devices Inc. ADP8870ACBZ-R7

Overview

ADP8870ACBZ-R7 from Analog Devices is a programmable 7-channel LED backlight driver IC with integrated charge-pump (1×/1.5×/2×), ambient light sensing (ALS) via two phototransistor inputs, and image-content-adaptive PWM dimming. It delivers up to 30 mA per channel for D1–D6 and 60 mA on D7, operates from 2.5 V to 5.5 V input, and supports I²C configuration. It targets mobile display backlighting where automatic brightness control based on ambient light and display content reduces power consumption.

For engineers reviewing the ADP8870ACBZ-R7 datasheet, ADP8870ACBZ-R7 pinout, ADP8870ACBZ-R7 application, or ADP8870ACBZ-R7 equivalent, this page provides verified technical context, exact pin functions, real-world application mappings, confirmed alternative parts with documented differences, and supply support for volume procurement and BOM continuity in portable electronics design.

Technical Context

The ADP8870ACBZ-R7 implements a dual-capacitor switched-capacitor charge-pump with automatic gain selection (1×, 1.5×, 2×) driven by internal logic that monitors minimum current-sink headroom voltage (VHR) across all active LED channels. Gain transitions include 100 μs stabilization delay and hysteresis to prevent oscillation.

It integrates two independent ALS comparators with five programmable light-sensing zones, dedicated D7 ALS control, and a PWM input that linearly scales output current (±1.4% linearity, 140 Hz–60 kHz range). All seven LED sinks are individually programmable for current (128-level DAC), fade timing (16 options, 0.1–5.5 sec), and group control via I²C interface operating at 400 kHz.

Key Specifications

Pinout & Package

ADP8870ACBZ-R7 is packaged in a 4 mm × 4 mm × 0.75 mm lead frame chip scale package (LFCSP) with exposed paddle (EP) requiring connection to GND for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM3530TMX/NOPB and TPS61165DRVR, the ADP8870ACBZ-R7 uniquely integrates dual ALS inputs, 7-channel drive with asymmetric D7 capability, and hardware-accelerated CABC - reducing host processing load and PCB area in compact mobile designs.

Availability

ADP8870ACBZ-R7 is available at Aetrix Electronics and suitable for mobile display backlighting, keypad lighting, and RGB LED indication requiring stable component supply, long-term lifecycle management, and traceable sourcing for consumer electronics production.

Supply support for ADP8870ACBZ-R7 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision instrumentation, communications, and power management markets since 1965.

The ADP8870 belongs to Analog Devices' backlight management IC product line, designed specifically for power-efficient, autonomous LED brightness control in battery-powered portable devices with minimal host processor involvement.

FAQ

What is the maximum total output current capability of the ADP8870ACBZ-R7?

The ADP8870ACBZ-R7 supports up to six LED channels (D1–D6) at 30 mA each and one channel (D7) at 60 mA, yielding a maximum combined output current of 240 mA. This rating assumes proper thermal management using the exposed paddle and operation within the specified junction temperature range (−40°C to +125°C). The actual achievable current depends on charge-pump gain mode, input voltage, and LED forward voltage.

Does the ADP8870ACBZ-R7 require external components for basic operation?

Yes, the ADP8870ACBZ-R7 requires four external capacitors: two for the charge-pump (C1+, C1−, C2+, C2−), one input bypass (1 μF on VIN), and one output filter (1 μF on VOUT). Phototransistor ALS inputs need 0.1 μF decoupling to GND, and I²C lines require pull-up resistors. No external inductor or diode is needed - the charge-pump architecture eliminates magnetic components.

How does the ADP8870ACBZ-R7 handle thermal overload?

The ADP8870ACBZ-R7 incorporates thermal shutdown (TSD) that activates at 150°C junction temperature with 20°C hysteresis. Upon triggering, the device disables all LED sinks and charge-pump, isolates VOUT from VIN, and asserts nINT. Recovery occurs automatically once junction temperature falls below 130°C. This behavior is fully hardware-based and requires no I²C command or host intervention.

Can the ADP8870ACBZ-R7 operate with only one phototransistor?

Yes, the ADP8870ACBZ-R7 supports single-sensor operation using only CMP_IN (Pin 18). The second phototransistor input is optional and maps to D6 (Pin 17) when enabled. If unused, D6 functions solely as an LED sink. Configuration is controlled via I²C registers - no hardware modification is needed to disable the second ALS path.

What is the purpose of the nINT pin on the ADP8870ACBZ-R7?

The nINT pin on the ADP8870ACBZ-R7 is an open-drain interrupt output that signals events including backlight turn-off, ALS threshold crossing, fault conditions (short-circuit, overvoltage, overtemperature), and fade completion. It eliminates the need for continuous I²C polling and enables event-driven power management in host processors - improving system responsiveness and reducing average current draw.