LT1671 60ns, Low Power, Single Supply, Ground-Sensing Comparator UFEATURESDESCRIPTIO ■ Low Power: 450 µ A The LT®1671 is a low power 60ns comparator with comple- ■ Fast: 60ns at 20mV Overdrive mentary outputs and latch. The input common mode 85ns at 5mV Overdrive range extends from 1.5V below the positive supply down ■ Low Offset Voltage: 0.8mV to the negative supply rail. Like the LT1394, LT1016 and ■ Operates Off Single 5V or Dual ±5V Supplies LT1116, this comparator has complementary outputs ■ Input Common Mode Extends to Negative Supply designed to interface directly to TTL or CMOS logic. The ■ No Minimum Input Slew Rate Requirement LT1671 may operate from either a single 5V supply or dual ■ Complementary TTL Outputs ±5V supplies. Low offset voltage specifications and high ■ Inputs Can Exceed Supplies without Phase Reversal gain allow the LT1671 to be used in precision applications. ■ Pin Compatible with LT1394, LT1016 and LT1116 The LT1671 is designed for improved speed and stability ■ Output Latch Capability for a wide range of operating conditions. The output stage ■ Available in 8-Lead MSOP and SO Packages provides active drive in both directions for maximum speed into TTL, CMOS or passive loads with minimal UAPPLICATIO S cross-conduction current. Unlike other fast comparators, the LT1671 remains stable even for slow transitions ■ High Speed A/D Converters through the active region, which eliminates the need to ■ Zero-Crossing Detectors specify a minimum input slew rate. ■ Current Sense for Switching Regulators ■ The LT1671 has an internal, TTL/CMOS compatible latch Extended Range V/F Coverters ■ for retaining data at the outputs. The latch holds data as Fast Pulse Height/Width Discriminators ■ long as the LATCH pin is held high. Device parameters High Speed Triggers ■ such as gain, offset and negative power supply current are Line Receivers ■ not significantly affected by variations in negative supply High Speed Sampling Circuits voltage. , LTC and LT are registered trademarks of Linear Technology Corporation. UTYPICAL APPLICATIOPropagation Delay vs Overdrive 140 1MHz Crystal Oscillator VS = ±5V VSTEP = 100mV 5V 120 TA = 25°C RL = 1M 1MHz CRYSTAL 2k (AT-CUT) 100 80 TIME (ns) + FALLING EDGE (tPDHL) LT1671 OUTPUT 60 2k – 40 2k RISING EDGE (tPDLH) 0.068µF 20 0 10 20 30 40 50 1671 TA01 1671 TA01 OVERDRIVE (mV) 1671 TA02 1