New Industry Products

Fairchild Semiconductor Releases New Line of Operational Amplifiers

May 03, 2001 by Jeff Shepard

Fairchild Semiconductor International (San Jose, CA) introduced a new family of operational amplifiers. The five new products offer a range of performance levels, from 75MHz at 0.5mA supply current to 7.3MHz at 70µ supply current. The KM4110, for example, has a slew rate of 50V/µs and provides a combination of industry-leading bandwidth of 75MHz and low noise level of 12nV/vHz. These voltage feedback amplifiers are designed for low-cost, battery-powered commercial applications, including cellular and cordless phones, PDAs, smart-card readers and telecom products.

Using a bipolar design, Fairchild claims that the amplifiers typically provide ten times more bandwidth and slew rate than CMOS amplifiers in the same supply current class. A proprietary gain stage allows the amplifiers to achieve as much as a 50-percent higher slew rate (50V/µs for the KM4110) with a low supply current (0.5mA). With extremely low supply current of less than 70µA, the KM4112 is designed to achieve 7MHz gain-bandwidth with slew rate of 9V/µs. For higher-bandwidth applications that allow for increased supply current, the KM4111 and KM4121 offer a 35MHz bandwidth and 27V/µs slew rate, with only 0.2mA.

In addition, the KM4120 and the KM4121 are similar to KM4110 and KM4111, except they have an active-low disable pin that can be used to lower their supply current to less than 30µA. This feature reduces power consumption in the standby mode. The output stage of all five products is short-circuit protected and offers "soft" saturation protection that improves recovery time. These amplifiers are designed to operate from +2.5V to +5.5V or ±1.25V to ±2.5V supplies.

Single versions are available in SOT23-5 (KM4110/ KM4111/ KM4112), and with the disable feature in SOT23-6 (KM4120/ KM4121). Dual versions (KM4210/ KM4211/ KM4212) will be offered in SOIC-8 and MSOP-8 packages and will be available for sampling in the second quarter of 2001. Pricing is $0.55 each in 1,000-piece quantities for the KM4110/KM4120; $0.58 each in 1,000-piece quantities for the KM4111/KM4121; and $0.64 each in 1,000-piece quantities for the KM4112. Samples, evaluation boards and production quantities are all currently available.