The LTC2609/LTC2619/LTC2629 incorporate a power-on reset circuit. During power-up, the voltage outputs rise less than 10mV above zero scale; after power-up, they stay at zero scale until a valid write and update take place. The power-on reset circuit resets the LTC2609-1/LTC2619-1/ LTC2629-1 to midscale. The voltage outputs stay at midscale until a valid write and update take place.