Analog Devices Inc./Maxim Integrated MAX8795AGTJ+

Overview

MAX8795AGTJ+ from Maxim Integrated is a TFT-LCD DC-DC converter IC integrating a 1.2MHz current-mode step-up regulator (20V/3A n-channel MOSFET), dual linear-regulator controllers (VGON/VGOFF), five rail-to-rail op-amps (±130mA, 45V/µs, 20MHz), and a logic-controlled high-voltage switch with adjustable delay - all in a single 32-pin TQFN package. It powers source/gate drivers and VCOM/gamma strings in ultra-thin LCD panels.

For engineers reviewing the MAX8795AGTJ+ datasheet, MAX8795AGTJ+ pinout, MAX8795AGTJ+ application, or MAX8795AGTJ+ equivalent, this device supports high-efficiency (>85%), fast transient response, ±1% output voltage accuracy, thermal fault latching, and automotive-grade operation (–40°C to +105°C) - critical for notebook, monitor, and automotive display power architectures.

Technical Context

The MAX8795AGTJ+ implements a synchronous current-mode boost architecture with integrated 20V/3A n-channel power MOSFET and 1.2MHz switching frequency, enabling compact LC filtering using ceramic capacitors and sub-2mm inductors. Its feedback loop uses a transconductance error amplifier (75–280 µS) with 700V/V gain and soft-start (14ms).

It integrates two independent linear-regulator controllers: FBP-based VGON (1.25V reference, ±1.5% load regulation) and FBN-based VGOFF (1.0V reference, ±25mV load regulation), each driving external pass transistors. Five op-amps feature rail-to-rail I/O, ±75mA continuous output, and are powered by VSUP (6–18V), supporting gamma correction and VCOM buffering.

Key Specifications

Pinout & Package

MAX8795AGTJ+ is housed in a lead-free, RoHS-compliant 32-pin thin QFN (TQFN) package with exposed paddle (EP) tied to AGND. The 0.8mm maximum thickness meets mechanical constraints of slim LCD assemblies.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar TFT-LCD power management applications.

Compared with MAX8795AGTJ+, the MAX8795AETJ+ offers identical electrical performance but reduced thermal margin, while the MAX8795AGCJ+ trades compactness for manufacturability - making MAX8795AGTJ+ optimal for space- and temperature-critical automotive and ultra-slim display designs.

Availability

MAX8795AGTJ+ is available at Aetrix Electronics and suitable for notebook computer displays, automotive instrument clusters, and industrial HMI panels requiring stable component supply, automotive-grade temperature resilience, and long-term production continuity.

Supply support for MAX8795AGTJ+ 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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for demanding electronic systems.

The MAX8795A product line was designed specifically for TFT-LCD display power architectures - integrating boost conversion, gate-driver bias generation, and gamma/VCOM amplification into one thermally robust, space-efficient IC.

FAQ

What is the maximum allowable input voltage for MAX8795AGTJ+?

The MAX8795AGTJ+ supports an absolute maximum input voltage of 6.0V, but continuous operation above 5.5V is not recommended. Per datasheet Note 2, operation between 5.5V and 6.0V should be limited to no more than 1% of the IC's lifetime. For reliable long-term use, keep VIN ≤ 5.5V. This limit ensures safe operation of internal circuitry including the IN-to-AGND rating (–0.3V to +7.5V) and prevents accelerated aging of the integrated MOSFET.

Does MAX8795AGTJ+ include built-in protection features?

Yes, MAX8795AGTJ+ incorporates multiple hardware-level protections: timer-delayed fault latching (200ms delay before shutdown on FB/FBP/FBN faults), thermal-overload shutdown at +150°C junction temperature with +15°C hysteresis, input undervoltage lockout (2.25V typical threshold), and overvoltage fault detection on SUP (19.9V max). These features operate autonomously without software intervention, ensuring robustness in unattended display systems.

Can the five operational amplifiers in MAX8795AGTJ+ drive capacitive loads directly?

The five op-amps in MAX8795AGTJ+ are specified for ±75mA continuous output current and ±130mA short-circuit current, with 45V/µs slew rate and 20MHz bandwidth. While they tolerate moderate capacitive loads (e.g., <100pF) in unity-gain buffer configurations, driving large capacitive loads (>1nF) such as long VCOM traces requires external isolation resistors (e.g., 10–50Ω in series) to maintain stability. Layout best practices - including local 0.1µF SUP-to-BGND bypassing - are essential for high-frequency performance.

How is the high-voltage switch in MAX8795AGTJ+ controlled and sequenced?

The MAX8795AGTJ+ high-voltage switch is controlled via two pins: CTL (logic select) and DEL (delay capacitor). When CTL = high, the SRC-to-COM path closes (R_SRC(ON) = 5–12Ω); when CTL = low, the DRN-to-COM path closes (R_DRN(ON) = 30–70Ω). Startup sequencing is set by a capacitor on DEL - charging to 1.25V before CTL becomes active. This ensures gate-on/off supplies stabilize before enabling the high-voltage path, preventing latch-up in TFT backplane circuits.

What is the purpose of the separate AGND, PGND, and BGND pins on MAX8795AGTJ+?

MAX8795AGTJ+ uses three dedicated ground pins to isolate noise domains: AGND (analog ground for step-up and linear regulators), PGND (power ground for LX switching node and MOSFET source), and BGND (analog ground exclusively for the five op-amps). These must be connected together *underneath the IC* via a low-inductance copper pour - not daisy-chained - to prevent switching noise from corrupting sensitive analog feedback and op-amp signals. The exposed paddle (EP) must also connect to AGND.