STMicroelectronics has introduced fast-starting intelligent power switches for safety-instrumented systems. They are designed to meet IEC 61131-2.
“With power-on delay time of less than 60µs, the IPS160HF and IPS161HF satisfy standardised requirements for interface types C and D in Safety Integrity Level (SIL) Class 3 applications,” according to the company. They will drive complex resistive, capacitive and inductive loads with one side connected to ground, such as valves, relays, and lamps”.
Input range is 8 – 60V, maximum switch resistance is 120mΩ, and rise and fall times are 10µs with 20µs propagation delay.
IPS160HF is rated at 2.5A output current, and IPS161HF for 0.7A. Both will withstand an applied supply voltage of up to 65, and integrate active-clamp circuitry for handling inductive loads.
A common diagnostic open drain output pin reports open load in off-state, over-load cut-off and thermal shut-down.
Open load protection, which can detect a broken wire between chip output and load circuit, is activated by connecting a resistor between the Vcc line and output pin – the data sheet has a detailed description in section 6.4.
As well as safety-related applications, use is also foreseen in factory automation: process control, PLCs (programmable logic controllers) and CNC (computer controlled) machines.
Packaging is a PowerSSO12 surface-mount.
Source: Electronicsweekly
