Electronic fuse ICs for power line circuit protection in industrial and consumer applications

Toshiba Electronics Europe GmbH has expanded its electronic fuse (eFuse) lineup with the introduction of the 40V TCKE6 series. The five new products are the TCKE601RA, TCKE601RL, TCKE602RM, TCKE603RA, and TCKE603RL. The eFuse ICs are ideal for use in industrial equipment, such as robots and PLCs, as well as consumer equipment, including robotic vacuum cleaners and copy machines.

The series is designed to perform multiple functions needed for robust power line circuit protection. While the products supply short-circuit protection similar to standard physical fuses, such as glass tube fuses and chip current fuses, they also include current-limiting and overvoltage protection. These improved features are crucial for protecting subsequent ICs in the circuit by preventing excessive current or voltage from being applied during overcurrent or overvoltage events. Furthermore, the eFuse ICs include a built-in thermal protection function that immediately shuts down the device if abnormal heat is detected or an unexpected short circuit occurs, also protecting the downstream circuit.

A key advantage of incorporating these protection functions into a single eFuse IC is the simplification of circuit design. By decreasing the necessity for multiple discrete components, the series allows more compact and efficient designs, resulting in fewer parts and a smaller footprint. The products are housed in a small TSOP6F package, typically measuring 2.9mm x 2.8mm, which helps reduce board size. The package height is typically 0.8mm, allowing thinner and more compact designs.

The series is rated at 40V and supports a wide input voltage range from 3.3V to 30V. This makes the products appropriate for various power management applications, including 5V, 9V, 12V, and 24V systems. The low on-resistance (RON), which is typically 53mΩ at an output current (IOUT) of 1A, minimises power dissipation during operation for optimum efficiency. The maximum RON is 90mΩ under these conditions. The rapid output short-circuit response time (tSHORT) is typically 0.1µs at 25C, which improves system reliability.

The TCKE6 series offers flexible operating modes tailored to the design requirements. The recovery operation type for the TCKE601RA and TCKE603RA is auto-retry, which enables the device to recover from faults automatically. The TCKE601RL and TCKE603RL are latched types that need an external signal for recovery. Designers can also select products featuring a FLAG function, which detects and reports abnormal conditions, or an enable (EN) function, which controls the eFuse IC’s operation. For added flexibility, the TCKE602RM enables mode switching between auto-retry and latched types via external signals, eliminating the need for FLAG or EN functions.