The TC7106A and TC7107A 3-1/2 digit direct display drive Analog-to-Digital Converters allow existing TC7106/TC7107 based systems to be upgraded. Each device has a precision reference with a 20 ppm/°C maximum temperature coefficient. This represents a 4 to 7 times improvement over similar 3-1/2 digit converters. Existing TC7106 and TC7107 based systems may be upgraded without changing external passive component values. The TC7107A drives common anode light emitting diode （LED） displays directly with 8 mA per segment. A low cost， high resolution indicating meter requires only a display， four resistors， and four capacitors. The TC7106A low-power drain and 9V battery operation make it suitable for portable applications. The TC7106A/TC7107A reduces linearity error to less than 1 count. Rollover error – the difference in readings for equal magnitude， but opposite polarity input signals， is below ±1 count. High-impedance differential inputs offer 1 pA leakage current and a 1012Ω input impedance. The differential reference input allows ratiometric measurements for ohms or bridge transducer measurements. The 15 μVP–P noise performance ensures a “rock solid” reading. The autozero cycle ensures a zero display reading with a zero volts input.