Monolithic Power Systems Inc. MP4864AGBD

Overview

MP4864AGBD from Monolithic Power Systems is a 64-channel, high-voltage SPST analog switch with integrated output bleed resistors, designed for medical ultrasound transmit/receive multiplexing. It supports ±90V analog signal switching, ±2A peak current per channel, 14Ω typical on-resistance, and operates from 3.3V logic and 12V translator supplies in a BGA-144 package.

For engineers reviewing the MP4864AGBD datasheet, MP4864AGBD pinout, MP4864AGBD application, or MP4864AGBD equivalent, this device addresses high-voltage analog routing challenges in time-critical beamforming systems where low charge injection (29pC), -66dB off-isolation at 5MHz, and cascaded serial control (DIN/DOUT/CLK/LEB) are essential selection criteria.

Technical Context

The MP4864AGBD implements a two-stage digital control architecture: a 64-bit serial shift register followed by a parallel 64-bit latch, enabling precise per-channel SPST switching via LEB-controlled data transfer. All 64 switches operate without external high-voltage bias rails-only VLL (2.7–5.5V) and VDD (10–14V) supplies are required.

Each channel integrates an output bleed resistor (20–50kΩ) to discharge residual voltage after switch turn-off, critical for echo signal integrity in ultrasound receive paths. Switch timing is synchronized to an 80MHz clock with 1ns setup/hold and 2µs turn-on/turn-off times, supporting fast beam steering across 64 transducer elements.

Key Specifications

Pinout & Package

BGA-144 (10mm × 10mm) package with 0.8mm ball pitch, MSL Level 3, bottom-side thermal pad for junction-to-board heat dissipation. Pin mapping validated per MPS MP4864A Rev. 1.0 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSM1014IPWR and ADG5462FBCPZ-RL7, the MP4864AGBD uniquely delivers 64-channel density, ±90V capability, integrated bleed termination, and serial control in one BGA package-making it the only solution qualified for FDA-cleared portable ultrasound beamformers requiring zero external HV infrastructure.

Availability

MP4864AGBD is available at Aetrix Electronics and suitable for medical ultrasound imaging systems, non-destructive testing equipment, and high-density transducer array controllers requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP4864AGBD 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance power management and analog ICs, with design centers in the US, China, and Taiwan.

The MP4864AGBD belongs to MPS's high-voltage analog switch product line, engineered specifically for medical and industrial ultrasound systems requiring integrated T/R switching, minimal external components, and regulatory-ready reliability.

FAQ

What is the maximum allowable analog signal voltage for MP4864AGBD?

The MP4864AGBD supports analog signals from 0V to ±90V under recommended operating conditions. Absolute maximum ratings extend to ±105V, but sustained operation above ±90V risks exceeding thermal limits and degrading switch lifetime. Operation must remain within the specified ±90V range for medical ultrasound compliance and guaranteed performance.

Does MP4864AGBD require negative high-voltage supplies?

No. The MP4864AGBD eliminates the need for negative or positive high-voltage supplies entirely. It operates using only two low-voltage rails: VLL (2.7–5.5V) for logic and VDD (10–14V) for internal level translation. This patented architecture removes HV DC-DC converters, bypass capacitors, and associated safety certifications required by traditional ±100V switch designs.

How does the output bleed resistor function during ultrasound receive mode?

Each SWOUT pin integrates a 20–50kΩ bleed resistor to ground. After a transmit pulse ends and the switch opens, this resistor actively discharges the PZT transducer's inherent capacitance (typically 1–5nF) within ~10–50µs. This prevents residual voltage from appearing as a false echo in the receive path, directly improving near-field image clarity and dynamic range.

Can multiple MP4864AGBD devices be synchronized for larger arrays?

Yes. The DIN/DOUT interface enables seamless daisy-chaining: DOUT of one device connects to DIN of the next, with shared CLK and LEB signals. Up to four MP4864AGBDs (256 channels) can be controlled using only four FPGA pins. Propagation delay through DOUT is ≤11ns, ensuring sub-nanosecond skew across cascaded devices for coherent beamforming.

What is the thermal resistance and maximum power dissipation of MP4864AGBD?

The BGA-144 package has θJA = 21°C/W and θJC = 4°C/W. At TA = 25°C, maximum continuous power dissipation is 4.8W. Under full 64-channel switching at 50kHz, IDD averages 22mA at 12V (264mW), well below thermal limits. For sustained ±2A peak currents, pulsed operation with ≤1% duty cycle keeps junction temperature within -25°C to +125°C range.

Is MP4864AGBD compliant with medical device safety standards?

The MP4864AGBD is RoHS-compliant, halogen-free, and rated for operation from -25°C to +125°C junction temperature. While the IC itself is not certified to IEC 60601, its architecture-eliminating HV buses, external capacitors, and fault-prone discrete HV generation-enables system-level compliance. Reference designs from MPS demonstrate pass/fail results for creepage, leakage current, and dielectric strength when used per layout guidelines.

What is the significance of -66dB off-isolation at 5MHz?

This specification quantifies signal rejection between an active channel and adjacent inactive channels at 5MHz-the fundamental frequency of many ultrasound imaging bands. -66dB means only 0.05% of the transmit signal couples into neighboring receive paths, preserving >55dB system dynamic range. This directly enables detection of weak echoes from deep tissue layers without masking by crosstalk artifacts.