Analog Devices Inc./Maxim Integrated MAX14866UTM+

Overview

MAX14866UTM+ from Maxim Integrated is a 16-channel, high-voltage (±110V), analog SPST switch designed for ultrasound transmit/receive multiplexing. It operates from a single +5V supply (no HV rails required), delivers 7Ω typical R_ON, <100pC charge injection, and 50MHz large-signal bandwidth-enabling high-fidelity beamforming in medical ultrasound probes.

For engineers reviewing the MAX14866UTM+ datasheet, MAX14866UTM+ pinout, MAX14866UTM+ application, or MAX14866UTM+ equivalent, key selection criteria include HV analog range (±105V AC), SPI-controlled per-channel switching (30MHz), SOI-based latchup immunity, and dual-package support (48-pin TQFN/110-bump WLP) for space-constrained in-probe integration.

Technical Context

The MAX14866UTM+ implements 16 independent analog switches using latchup-free Silicon-on-Insulator (SOI) process technology, enabling robust operation under ±110V COM/NO voltage stress and resonant load transients common in ultrasound systems. Its architecture separates low-voltage digital control (VDD = 1.7–5.5V) from high-voltage analog paths (COM/NO), with integrated bleed resistors for transducer discharge.

Switch state control is implemented via a 16-bit SPI shift register (MSB-first, 30MHz max) with transparent latch (LE), plus asynchronous global SET/CLR inputs. Daisy-chain capability supports multi-chip probe head configurations without additional logic, while timing-critical HV burst transmission inhibits SPI writes during ±2V+ analog activity to prevent corruption.

Key Specifications

Pinout & Package

MAX14866UTM+ is packaged in a 48-pin, 7mm × 7mm, 0.5mm-pitch TQFN with exposed thermal pad (EP). Pin 1 is COM0; pins 2–36 carry alternating COMx/NOx terminals for all 16 channels; pins 37–48 provide digital control (LE, DOUT, VDD, VCC, DIN, CLK, SET, CLR) and ground connections.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage analog switch applications.

Compared with MAX14865UTM+, MAX14866UTM+ provides 40% higher voltage range and 43% wider bandwidth-critical for modern elastography and contrast-enhanced ultrasound. Versus ADG5412BRUZ, it offers 4× channel count, integrated control, and probe-optimized SOI robustness, but requires SPI firmware integration.

Availability

MAX14866UTM+ is available at Aetrix Electronics and suitable for medical ultrasound imaging, non-destructive testing, relay replacement, and industrial printer applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for MAX14866UTM+ 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 power management ICs for demanding industrial, medical, and communications applications.

The MAX14866UTM+ belongs to Maxim's high-voltage ultrasound interface product line, engineered specifically for compact, safe, and high-fidelity beamforming in next-generation portable and diagnostic ultrasound systems.

FAQ

What is the maximum allowable voltage across COM and NO pins for MAX14866UTM+?

The absolute maximum voltage between any COMx and NOx pin is ±110V. For reliable linear operation, the analog dynamic signal range is specified as ±105V AC (f > 500kHz), supporting up to 210V_PKPK undistorted transmit bursts. Exceeding ±110V risks permanent damage, and operation above ±105V may degrade linearity or increase charge injection beyond 100pC.

Can MAX14866UTM+ operate from a single 5V supply, and what are the implications?

Yes, MAX14866UTM+ can operate from a single +5V supply by connecting VCC and VDD together, provided all digital control signals (DIN, CLK, LE, SET, CLR) are also at 5V logic levels. This eliminates the need for separate logic and analog supplies, simplifying probe-level power design-but requires careful attention to ground noise coupling between digital and HV analog sections.

How does the MAX14866UTM+ handle transducer discharge between pulses?

MAX14866UTM+ integrates internal bleed resistors that automatically discharge transducer capacitance when switches are opened. The resistor value depends on switch state (typically ~80kΩ when ON, ~50kΩ when OFF), ensuring rapid voltage decay and preventing residual charge from causing image artifacts or false triggering in subsequent receive cycles.

Is daisy-chaining supported for multiple MAX14866UTM+ devices, and how is it implemented?

Yes, MAX14866UTM+ supports daisy-chaining via its DOUT pin, which outputs the DIN signal delayed by exactly 16 clock cycles. To chain N devices, connect DOUT of device N−1 to DIN of device N, while sharing CLK, LE, SET, and CLR across all units. Pulse LE low simultaneously to update all latches, enabling synchronized switching across large transducer arrays.

Why does the MAX14866UTM+ prohibit SPI programming during HV transmission?

MAX14866UTM+ features an internal transmit detector that disables SPI writes for up to 4.5µs whenever a ±2V+ analog signal is sensed on COM/NO pins. This prevents metastability or incorrect latch updates caused by high-frequency switching noise during HV burst transmission-ensuring deterministic switch behavior and long-term reliability in ultrasound systems.