CT455 / CT456 – High-Speed Contactless Current Sensors

Sensor Introduction

The CT455 and CT456 are ultra-fast, high-precision, contactless current sensors using Allegro’s proprietary XtremeSense™ TMR technology. Engineered for high-reliability applications in automotive, industrial, and energy systems, these sensors offer

• 1 MHz analog bandwidth
• <300 ns fast response time
• Low power consumption (~6 mA)
• AEC-Q100 Grade 1 qualified
• Compact 8-lead TSSOP or SOIC packaging

CT455:

• Single-ended sensing
• ±6 mT to ±48 mT magnetic field range
• Available in both factory-calibrated and user-programmable options
• Ideal for flexible integration in PCB-based measurement systems

CT456:

• Differential sensing with >90% stray field immunity
• ±12 mT and ±24 mT field range options
• Ideal for noisy environments and high dV/dt switching nodes

Requires no external magnetic core due to high sensitivity and common-mode rejection

Demo Board Overview

The LiveBench evaluation board provides complete remote test and validation capabilities with:

• ±200 A sweep current
• Analog voltage readout and dynamic plot generation
• Programmable profiles for DC sweep, hysteresis, and repeatability
• Heatmap visualizations near the sensor-busbar notch for thermal performance testing

Target Applications

• DC-DC Converters – High-Speed Current Monitoring
• Battery Management Systems (BMS)—Charge/discharge tracking
• Solar Inverters/MPPT—Current optimization for power harvesting
• On-board Chargers (OBC)—Fast control loop feedback
• Smart Fusing—Trigger protection using programmable thresholds