LinFinity Intros LX432 Low-Voltage Shunt RegulatorJune 06, 1999 by Jeff Shepard
The LinFinity Divison of Microsemi Corp. (Santa Ana, CA) recently introduced the LX432 low-voltage shunt regulator for isolated power supplies of less than 4V output, for low-cost low-dropout regulation of 2.5V and below, and for applications requiring a precision low-voltage reference. The new device is available in both 3-pin and 5-pin SOT-23 surface-mount packages and in TO-92 3-pin through-hole packaging, making it a drop-in replacement for popular TL431 regulators that are unsuited for an increasing number of low voltage applications. The LX432 has a reference voltage of 1.24V compared to the 2.5V reference of the TL431. All versions provide a 1.24V reference voltage with an initial accuracy of 1 percent. Output voltage may be set to any value between 1.24V and 20V by two external resistors. For improved load regulation, the LX432 Series offers a low output impedance, typically 250 milliohms. With an operating current as low as 80uA, the devices are designed for portable and micropower applications. Low voltage operation enables the LX432 to be used in the feedback loop of isolated low-voltage power supplies (ac/dc or dc/dc) with a regulated output of 3.3V or less. Commercial versions of the LX432 in OEM quantities of 1,000 are priced at $0.53 for the 3-pin or 5-pin SOT-23 package and at $0.44 in a 3-pin TO-092 through-hole package. Devices packaged for industrial environments are priced at $0.79 and $0.70, respectively. Samples and production quantities are available immediately.