Analog Devices Inc./Maxim Integrated MAX17690EVKITB#

Overview

MAX17690EVKITB# from Maxim Integrated is an evaluation kit for the MAX17690 peak-current-mode, fixed-frequency isolated flyback controller operating in DCM. It enables no-optocoupler, primary-side regulation of 5V/1A isolated outputs from 18–36V DC input, with programmable 50–250kHz switching, 2A/4A gate drive, and integrated thermal/hiccup protection. The kit supports design validation of wide-input (4.5–60V), high-efficiency flyback power supplies.

For engineers reviewing the MAX17690EVKITB# datasheet, MAX17690EVKITB# pinout, MAX17690EVKITB# application, or MAX17690EVKITB# equivalent, this evaluation platform provides verified reference schematics, layout, BOM, and performance data-including efficiency vs. load (≥85% at full load), output voltage regulation (±5%), transient response, and soft-start timing-to accelerate development of industrial and telecom isolated DC-DC converters.

Technical Context

The MAX17690EVKITB# implements a primary-side sensing algorithm that samples the reflected flyback voltage near secondary zero-current to reject transformer parasitics and diode forward-voltage drift. It uses internal PTAT current injection via the TC pin (0.55V bias, +1.85mV/°C) to compensate for diode V_F temperature coefficient (–1 to –2mV/°C), enabling stable ±5% output regulation across –40°C to +125°C.

This kit validates the MAX17690's core control architecture: a 16-pin TQFN-based controller with 7V INTVCC LDO, EN/UVLO (1.215V turn-on), OVI (1.215V overvoltage trip), and NDRV driver delivering 2A source / 4A sink into MOSFET gates. It demonstrates real-world implementation of R_RT-programmed frequency, R_SET/R_FB/R_TC resistor networks, and hiccup-mode short-circuit protection triggered after 16,384 clock cycles.

Key Specifications

Availability

MAX17690EVKITB# is available at Aetrix Electronics and suitable for industrial PLC I/O modules, telecom power interfaces, and wide-input isolated DC-DC converter development requiring stable component supply, rapid prototyping support, and production-ready reference designs.

Supply support for MAX17690EVKITB# 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 solutions for industrial, automotive, and communications systems.

The MAX17690 product line delivers no-optocoupler isolated flyback controllers targeting cost-sensitive, space-constrained applications where reliability, wide input range, and precise primary-side regulation are critical-especially in PLCs, base stations, and distributed power architectures.

FAQ

What is the purpose of the MAX17690EVKITB# evaluation kit?

The MAX17690EVKITB# is a fully assembled and tested evaluation platform for the MAX17690 no-optocoupler isolated flyback controller. It demonstrates a complete 5V/1A isolated power supply design using primary-side regulation, enabling engineers to validate performance metrics-including efficiency, regulation accuracy, transient response, and protection behavior-before committing to custom PCB design. The kit includes schematic, layout files, BOM, and test reports for immediate lab use.

Does the MAX17690EVKITB# support input voltages outside 18–36V?

Yes. While the MAX17690EVKITB# is configured and tested for 18–36V input, the underlying MAX17690 IC supports 4.5–60V operation. The kit's input circuitry-including EN/UVLO and OVI resistor dividers-is designed to be reconfigured for other ranges. For example, adjusting R_EN/R_OVI allows startup at 12V or overvoltage protection at 56V, maintaining full functionality of the MAX17690EVKITB# as a flexible development tool.

How does the MAX17690EVKITB# achieve ±5% output regulation without an optocoupler?

The MAX17690EVKITB# leverages the MAX17690's proprietary primary-side sensing algorithm, which samples the reflected flyback voltage at the transformer primary during secondary zero-current. This minimizes errors from diode V_F and leakage inductance. The kit implements temperature compensation via the TC pin (0.55V bias, +1.85mV/°C) and R_TC, counteracting the diode's negative V_F tempco (–1 to –2mV/°C). Together, these features deliver ±5% regulation across line, load, and temperature-verified on the MAX17690EVKITB# board.

Can the MAX17690EVKITB# be used to evaluate different output voltages?

Yes. The MAX17690EVKITB# supports configurable output voltages by modifying R_FB, R_SET, and R_TC values per the MAX17690 datasheet equations. Its transformer has multiple secondary taps, and the feedback network is accessible via test points and solder jumpers. Engineers have successfully reconfigured the MAX17690EVKITB# for 3.3V, 12V, and 15V outputs-retaining all protection features and regulation performance when following the design guidelines for R_IN, R_RIN, and sampling point calibration.

What protection features are validated on the MAX17690EVKITB#?

The MAX17690EVKITB# fully validates four key protections: (1) hiccup-mode short-circuit response-triggered within 16,384 clock cycles when output drops below 70% of nominal or runaway current limit (120mV on CS) occurs; (2) thermal shutdown at >160°C with 20°C hysteresis; (3) input overvoltage lockout via OVI pin (1.215V threshold); and (4) precise enable/UVLO (1.215V turn-on) with adjustable resistor divider. All are measured and documented in the MAX17690EVKITB# user guide.