Analog Devices Inc./Maxim Integrated MAX1765EVKIT

Overview

The MAX1765EVKIT from Maxim Integrated is a fully assembled and tested evaluation kit for the MAX1765 dual-output boost regulator IC, featuring two independent circuits-one in 16-pin QSOP (696mW dissipation) and one in 16-pin TSSOP-EP (1700mW)-each delivering +3.3V/800mA DC-DC output and +2.85V/500mA LDO output, optimized for low-input-voltage battery-powered systems.

For engineers reviewing the MAX1765EVKIT datasheet, MAX1765EVKIT jumper configuration, MAX1765EVKIT operating modes (PWM/PMF/track/shutdown), or MAX1765EVKIT alternative evaluation platforms, this board enables rapid validation of input voltage startup down to +0.7V, 1MHz switching efficiency up to 96%, and configurable output voltages (+2.5V to +5.5V DC-DC; +1.25V to +5V LDO) via external resistors and jumpers.

Technical Context

The MAX1765EVKIT implements two complete, functionally identical MAX1765-based power architectures on a single PCB: left-side low-power circuit (U1: MAX1765EEE in 16-pin QSOP) and right-side high-power circuit (U2: MAX1765EUE in 16-pin TSSOP-EP with exposed paddle). Both support input range +0.7V to +3.2V and offer pin-selectable modes via 3-pin headers (JU1–JU11).

Each circuit integrates an internal N-channel MOSFET switch and P-channel synchronous rectifier, enabling forced PWM, normal (PFM/PWM auto-switching), track mode (POUT = OUTL + 0.5V), and external clock synchronization (500kHz–1200kHz). LDO sourcing is jumper-configurable between POUT or external DC supply, and shutdown current is <1µA (typ) per IC.

Key Specifications

Availability

MAX1765EVKIT is available at Aetrix Electronics and suitable for battery-powered portable instrumentation, low-voltage IoT sensor nodes, and handheld medical devices requiring stable component supply, fast prototyping turnaround, and validated reference designs for ultra-low-input-voltage DC-DC conversion.

Supply support for MAX1765EVKIT 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 precision analog, mixed-signal, and power management solutions for industrial, automotive, and communications applications.

The MAX1765 product line delivers high-efficiency, ultra-low-input-voltage boost regulators with integrated LDOs-designed specifically for energy-constrained battery systems where startup below 1V and >95% peak efficiency are critical.

FAQ

What is the primary purpose of the MAX1765EVKIT?

The MAX1765EVKIT is a fully assembled evaluation platform for the MAX1765 boost regulator IC. It provides two independent, side-by-side circuits-left (QSOP) and right (TSSOP-EP)-to demonstrate and validate the IC's dual-output capability: +3.3V/800mA DC-DC and +2.85V/500mA LDO, with jumper-selectable modes, adjustable outputs, and ultra-low 0.7V startup. The MAX1765EVKIT enables immediate functional testing without soldering or component sourcing.

How do I configure the MAX1765EVKIT for forced PWM mode?

To configure forced PWM mode on either circuit, place shunts across pins 1–2 of jumpers JU2 (left) or JU8 (right), connecting CLK/SEL to POUT. This disables pulse-frequency modulation (PFM) at light loads and maintains constant 1MHz switching for noise-sensitive applications. The MAX1765EVKIT supports this setting out-of-box for both U1 and U2, and the mode is confirmed by stable ripple and absence of frequency modulation under varying load.

Can the MAX1765EVKIT operate from a 0.9V input source?

Yes-the MAX1765EVKIT supports input voltages as low as +0.7V DC. For inputs below +1.1V, a Schottky diode (e.g., Nihon EP10QY03) must be installed at D1 on the left-side circuit; the right-side circuit includes this diode pre-installed. With proper diode placement and jumper configuration (JU1/JU7 ONA=POUT), the MAX1765EVKIT reliably starts and regulates at 0.9V, delivering stable +3.3V and +2.85V outputs.

What are the key differences between the left and right circuits on the MAX1765EVKIT?

The left circuit uses MAX1765EEE in 16-pin QSOP (696mW thermal limit), while the right uses MAX1765EUE in 16-pin TSSOP-EP (1700mW, exposed paddle). Identical functionality includes +3.3V/800mA DC-DC, +2.85V/500mA LDO, 1MHz switching, and jumper-selectable modes. The MAX1765EVKIT allows direct thermal and power-handling comparison: the TSSOP-EP side sustains higher continuous load without derating, making it suitable for higher ambient temperature environments.

How do I adjust the LDO output voltage on the MAX1765EVKIT?

The factory-set +2.85V LDO output is configured by shorting the FBL pin to ground via PCB trace. To change it, cut the trace across R4 (left circuit) or R10 (right circuit), then install external resistor dividers between FBL, OUTL, and GND. Per the MAX1765 datasheet, V_OUTL = 1.25V × (1 + R_top/R_bottom). The MAX1765EVKIT supports full adjustment from +1.25V to +5.0V with appropriate resistor selection and layout.