Track-And-Hold Amplifer Offers Low Power

The SPT9110 track-and-hold amplifier achieves 100 MSPS operation and can function as a single-ended amplifier only, or in full configuration as a single-to-differential THA. Features include a 1.5V to 3.5V input range, PECL clock inputs, and inverting operational amplifier with gain of -1 and a 2.5V bandgap reference using a single 5V supply. Power consumption is 150 mW in single-to-differential mode and 75 mW in single-ended mode. The amplifier has separate power supply pins for the inverter and reference so that each can be optionally powered up and used independently. Sampling bandwidth is 400 MHz and track mode slew rate is 700 V/µs. Specifications include hold mode distortion of -66 dB at 50 MSPS and 25-MHz input frequency, and -58 dB at 100 MSPS and 50-MHz input. An internal hold capacitor is included to minimize drift, hold-mode leakage and reduce external component count. It's claimed that the amp can improve dynamic performance of analog-to-digital converters used in test instruments, RF demodulation, digital sampling oscilloscopes, and spectrum analyzers.