The HI-546, HI-547, HI-548, and HI-549 are analog multiplexers with active overvoltage protection and guaranteed rON matching. These devices allow analog input levels to greatly exceed the power supply voltage without damaging the device or disturbing the signal path of other channels. Active protection circuitry ensures that signal fidelity is maintained even under fault conditions that would destroy other multiplexers. Analog inputs can withstand constant 70VP-P levels even with ±15V supplies. Digital inputs can also sustain continuous faults up to 4V greater than either supply. In addition, signal sources are protected from short circuiting in the event of multiplexer supply loss, with each input presenting 1kΩ of resistance under this condition. These features make the HI-546, HI-547, HI-548, and HI-549 ideal for use in systems where the analog inputs originate from external equipment or separately powered circuitry. All devices are fabricated with 44V Dielectrically Isolated CMOS technology. The HI-546 is a single 16-Channel, the HI-547 is an 8-Channel differential, the HI-548 is a single 8-Channel, and the HI-549 is a 4-Channel differential device. If input overvoltage protection is not needed, the HI-506/507/508/509 multiplexers are recommended. For further information, see Application Notes AN520 and AN521. For MIL-STD-883 compliant parts, request the HI-546/883.
The HI‑546, HI‑547, HI‑548 and HI‑549 are 8‑ or 16‑channel CMOS analog multiplexers that feature active over‑voltage protection up to 70 Vp‑p and guaranteed on‑resistance matching. They can tolerate analog inputs that exceed the supply voltage without damage and present a 1 kΩ resistance under fault conditions. The devices are fabricated with 44 V dielectrically isolated CMOS technology and include break‑before‑make switching.
Typical applications include data acquisition, industrial controls and telemetry. The datasheet provides ordering information for various package types (CERDIP, PDIP, SOIC, PLCC), pinout diagrams, truth tables, functional and schematic diagrams, absolute maximum ratings, and electrical specifications such as access time, standby power and input thresholds.
| Analog Overvoltage Protection | 70 Vp‑p |
|---|---|
| Maximum Power Supply | 44 V |
| Standby Power (Typical) | 75 mW |
The devices can withstand constant 70 Vp‑p levels with +15 V supplies.
Yes, they are Pb‑Free Plus Anneal products and are RoHS compliant.