A dual rail driver for an electrochromic device is provided. The dual rail driver includes a power supply having a first power supply rail and a second power supply rail and an H bridge connected to the first power supply rail and the second power supply rail and configurable to couple to an electrochromic device. The dual rail driver includes a controller coupled to the H bridge through a failsafe module and configurable to control switches of the H bridge to charge and discharge the electrochromic device from the first power supply rail and the second power supply rail. The failsafe module is configurable to override one or more signals from the controller that controls the switches of the H bridge through the failsafe module, responsive to detecting anomaly of the electrochromic device.