AD835:  250 MHz, Voltage Output 4-Quadrant Multiplier

The AD835 is a complete four-quadrant, voltage output analog multiplier, fabricated on an advanced dielectrically isolated complementary bipolar process. It generates the linear product of its X and Y voltage inputs with a −3 dB output bandwidth of 250 MHz (a small signal rise time of 1 ns). Full-scale (−1 V to +1 V) rise to fall times are 2.5 ns (with a standard RL of 150 Ω), and the settling time to 0.1% under the same conditions is typically 20 ns.

Its differential multiplication inputs (X, Y) and its summing input (Z) are at high impedance. The low impedance output voltage (W) can provide up to ±2.5 V and drive loads as low as 25 Ω. Normal operation is from ±5 V supplies.

Though providing state-of-the-art speed, the AD835 is simple to use and versatile. For example, as well as permitting the addition of a signal at the output, the Z input provides the means to operate the AD835 with voltage gains up to about ×10. In this capacity, the very low product noise of this multiplier (50 nV/√Hz) makes it much more useful than earlier products.

The AD835 is available in an 8-lead PDIP package (N) and an 8-lead SOIC package (R) and is specified to operate over the −40°C to +85°C industrial temperature range.

APPLICATIONS

• Very fast multiplication, division, squaring
• Wideband modulation and demodulation
• Phase detection and measurement
• Sinusoidal frequency doubling
• Video gain control and keying
• Voltage-controlled amplifiers and filters

1. The AD835 is the first monolithic 250 MHz, four-quadrant voltage output multiplier.
2. Minimal external components are required to apply the AD835 to a variety of signal processing applications.
3. High input impedances (100 kΩ||2 pF) make signal source loading negligible.
4. High output current capability allows low impedance loads to be driven.
5. State-of-the-art noise levels achieved through careful device optimization and the use of a special low noise, band gap voltage reference.
6. Designed to be easy to use and cost effective in applications that require the use of hybrid or board-level solutions.