Texas Instruments UC1901 Isolated Feedback Generator UC1901J

The UC1901J Isolated Feedback Generator from Texas Instruments is designed for applications requiring feedback control across voltage isolation boundaries. It utilizes an amplitude-modulation system to couple an isolated feedback error signal via a small RF transformer or capacitor, serving as a cost-effective alternative to optical couplers. The device features an internal 1% reference voltage and an error amplifier, along with a programmable high-frequency oscillator capable of operating up to 5 MHz. The UC1901J can synchronize with an external clock, making it suitable for integration with various system clocks or switching frequencies in switch-mode power supplies (SMPS). It includes a loop status monitor that provides an active-low output when the sensed error voltage is within ±10% of the reference voltage. The device operates with a supply voltage range of 4.5V to 40V and is rated for a temperature range of -55°C to +125°C, making it versatile for different environmental conditions. Engineers may consider the UC1901J for projects that require reliable feedback mechanisms in isolated systems, particularly where cost and size constraints are critical.