Advantest 7461A/7451A Digital Multimeter

Advantest  7461A/7451A Digital Multimeter

High-speed and variable integration time DMM supporting multiple applications 

● Two models by use 6½-digit display (7461A) 5½-digit display (7451A) 

● Fast sampling : 20,000 readings/sec (7461A) 5,000 readings/sec (7451A) 

● Variable integration time: 10µs to 10s (7461A), 100µs to 10s (7451A) 

● High-resolution DCI measurement: 1nA (7461A), 10nA (7451A) 

● Two-channel DCV measurement 

● Full array of trigger functions

6½-digit (7461A) and 5½-digit (7451A) digital multimeters Achieve both high performance and low price

The 7461A and the 7451A are digital multimeters with 6½-digit and 5½-digit display respectively, providing high performance with low price. These multimeters realize high-speed sampling performance with selective sampling modes by adopting the newly developed A/D converter, supporting a variety of applications including digitization of pulse signals, logging measurement at certain intervals. As another feature, the integration time can be set to any values. This enables correctly measuring the average values of pulsed current/voltage, which cannot be measured by former models.

In addition to the conventional external trigger functions, extensive internal trigger functions have been added, allowing easy capturing of the measured data. Furthermore, these multimeters are provided with twochannel DC voltage measurement (Bch 10V range fixed), so that low cost measurement system architecture is available. Since both GPIB and USB interfaces are mounted as standard, it is easy to capture data, extending the support to automated production lines and other applications.

Features

■ High Speed Sampling

By adopting the newly developed variable integration time A/D converter, the 7461A and the 7451A realize the highest sampling rate of 20,000 readings per sec and 5,000 readings per sec with 3½-digit resolution respectively. The sampling interval can be set from 50µs to 3,600s for the 7461A, and from 200µs to 3,600s for the 7451A, which allows high-speed digitization and data logging at precise measurement intervals.

■ Variable Integration Time

The integration time can be set from 10µs to 10s for the 7461A and from 100µs to 10s for the 7451A, which allows you to easily measure the average current of cellular phones or LCDs. The newly developed A/D converter of which integration time can be set to any values is based on the analog integration technique, so that it provides precise average measurement data, differently from the digital method using a discrete sampling.

■ Full Array of Trigger Functions

Various types of measurements are supported by the built-in trigger functions such as the level trigger and the delta trigger. Maximum sampling rate: 200 readings/sec (from 5ms)

■ Low Power Resistance Measurement

In resistance measurement, measurement current may cause heat generation in a measured device and variation in its measured values. Low-power 2WΩ/4WΩ resistance measurement uses only 1/10 of the typical measurement current, minimizing the effect of thermal fluctuation

■ Easy System Configuration by Two-channel DCV Measurement

With the DCV-Bch input (10V range fixed), current measurement and two-channel voltage measurement can be switched, which enhances the measurement throughput. (Rating voltage between Bch Hi and COM:12V)

Applications

Standby Current Measurement of Cellular Phone

In a cellular phone, the peak current flows in the standby state at a constant period, and the base current flows in other states. This standby time varies depending on the adopted method. To measure the average current precisely, it is necessary to measure all current passing during the standby time. The 7461A and the 7451A are capable of current waveform measurement including peak current measurement by fast sampling of 20,000 readings and 5,000 readings per second respectively. Also, these models are capable of accurate average current measurement by using the variable integration time function, in which the integration time can be set to any value up to 10 seconds.

Rising Signal Measurement by Delta Trigger and Pre-Trigger

The delta trigger starts measurement by detecting the slope of a signal. This function is convenient for starting measurement when data increases or is stabilized after convergence, and also supports various kinds of change patterns.

The pre-trigger is used to capture data before the trigger event. This function is convenient for analyzing signal states, for example, when an abnormal measurement value is detected.

Thermistor Low-Power Resistance Measurement

The 7461A/7451A is equipped with the low-power resistance measurement function as standard. This enables measurement of a thermistor or other heat sensitive elements with reduced effect from self-heating. When a thermistor is measured in the 1kΩ range with the normal 4WΩ function, the measurement current is 1mA and the resistance values will change significantly. On the other hand, the LP4WΩ function is used, the measurement current is 100µA which is 1/10 the normal value 4WΩ, and there will be small change in resistance values.