Analog Devices Inc./Maxim Integrated MAX9250ECM+

Overview

MAX9250ECM+ from Maxim Integrated is a 27-bit DC-balanced LVDS deserializer IC for automotive and industrial video interfaces, converting serial LVDS input (5–42MHz) into 18-bit RGB video data and 9-bit control data with programmable latch edge, output enable, and ±2% reference clock tolerance. It operates from +3.3V core supply and supports 1.8V–3.3V logic-level outputs, targeting in-vehicle display systems.

For engineers reviewing the MAX9250ECM+ datasheet, MAX9250ECM+ pinout, MAX9250ECM+ application, or MAX9250ECM+ equivalent, key selection criteria include its output-enable-controlled busing capability, 48-pin LQFP package, -40°C to +85°C temperature range, and compatibility with MAX9247 serializer in AC-coupled links up to 42MHz.

Technical Context

The MAX9250ECM+ implements a PLL-based clock recovery architecture synchronized to the incoming LVDS stream and local REFCLK, with lock detection via transition-word search and clock-stretching during mode switching. Its deserialization path separates video (RGB_OUT[17:0]) and control (CNTL_OUT[8:0]) phases using DE_OUT signaling, enabling timing-efficient blanking-period data transfer.

It features proprietary DC-balanced encoding/decoding for AC-coupling support, five single-bit-error-tolerant control inputs (C0–C4), and staggered RGB output switching across three groups to reduce simultaneous switching noise. Output transition time scales with RNG[1:0]-selected frequency range (5–42MHz), and OUTEN enables high-impedance state for bus sharing.

Key Specifications

Pinout & Package

MAX9250ECM+ uses a 48-pin LQFP package with dedicated power domains (VCC, VCCO, VCCLVDS, VCCPLL), differential LVDS input (IN+/IN-), and segregated digital I/O groups for RGB, control, clock, and status signals. Pin functions are validated per Maxim's official MAX9250 datasheet Rev 5 (19-3943).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LVDS deserializer applications.

Compared with MAX9251ECM+, the MAX9250ECM+ offers identical functionality at lower cost and reduced thermal derating margin, while DS90UB925QSQ/NOPB introduces protocol-level complexity but adds bidirectional control and diagnostics - making MAX9250ECM+ optimal for cost-sensitive, fixed-temperature automotive display links.

Availability

MAX9250ECM+ is available at Aetrix Electronics and suitable for navigation system displays, in-vehicle entertainment systems, and LCD displays requiring stable component supply, automotive-grade qualification, and long-term production continuity.

Supply support for MAX9250ECM+ 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and high-speed interface ICs for automotive, industrial, and communications markets.

The MAX92xx family targets high-reliability serial video transmission in harsh environments, with the MAX9250ECM+ specifically engineered for low-EMI, AC-coupled LVDS deserialization in automotive display subsystems.

FAQ

What is the primary function of the MAX9250ECM+ in a video interface system?

The MAX9250ECM+ is a 27-bit LVDS deserializer that converts high-speed serial video and control data from a MAX9247 serializer into parallel 18-bit RGB video (RGB_OUT[17:0]) and 9-bit control (CNTL_OUT[8:0]) outputs. It recovers clock from the LVDS stream, provides DE_OUT-gated phase separation, and delivers deterministic timing for display controllers - all within a single 48-pin LQFP package.

Does the MAX9250ECM+ support AC-coupling, and why is that important?

Yes, the MAX9250ECM+ supports AC-coupling via its DC-balanced deserialization architecture. This allows placement of coupling capacitors between the serializer and deserializer to block ground potential differences and common-mode noise - critical for automotive applications where chassis-ground shifts and EMI can corrupt video signals. The internal 1.2V LVDS bias (via 42–78kΩ resistors) ensures reliable receiver operation with AC-coupled inputs.

How does the OUTEN pin on the MAX9250ECM+ enable output busing?

The OUTEN pin on the MAX9250ECM+ places all single-ended outputs (RGB_OUT[17:0], CNTL_OUT[8:0], DE_OUT, PCLK_OUT) into high-impedance state when driven low - except LOCK, which remains active. This allows two MAX9250ECM+ devices to share a common 18-bit RGB and 9-bit control bus, with one enabled (OUTEN = high) and the other disabled (OUTEN = low). Sequencing requires ≥30ns delay between disable and enable transitions to prevent bus contention.

What is the significance of the R/F pin on the MAX9250ECM+?

The R/F (Rising/Falling) pin on the MAX9250ECM+ selects whether RGB_OUT[17:0] and CNTL_OUT[8:0] are latched into downstream logic on the rising or falling edge of PCLK_OUT. Setting R/F = high configures rising-edge latching; R/F = low configures falling-edge latching. This flexibility ensures timing compatibility with diverse display controllers, FPGAs, or ASICs without requiring external flip-flop re-timing.

Can the MAX9250ECM+ operate with a reference clock that differs from the serializer's PCLK_IN frequency?

Yes - the MAX9250ECM+ requires REFCLK to be within ±2% of the serializer's PCLK_IN frequency for reliable PLL lock acquisition and stable operation. This tolerance accommodates crystal aging, temperature drift, and minor oscillator mismatches without requiring matched crystals across serializer/deserializer pairs. Once locked to REFCLK, the device synchronizes to the incoming LVDS stream and outputs recovered PCLK_OUT aligned to the serial data.