In addition to a breakdown voltage of 350V and switch resistance of 18 ohms at 180 mA, HT18LG and HT19LG also feature peak limiting current programmable by an external resistor to 200 mA min./300 mA max. with a value of 150 ohms. Off-state leakage current is 2 µA max. with input voltage of 100V. Each device has three control inputs, with the HKS pin turning the switch on when connected to the TPG pin, the LS pin allowing a logic signal to turn the switch on, and the dial pulse DP pin used to turn the switch off for pulse dialing. The HT18 has dial pulse active high and the HT19 is active low. The devices come in SO-8 packages.