FS9721B

Rev. 1.7

3/35

1

Description

FS9721B is a high performance, low power consumption, 3⅔ digits (2400 Counts) Analog/Digital

Converter (ADC+MCU) that is embedded microprocessor. It contains 8 bit microprocessor, low noise and

high stability operation amplifier, AC conmutation operation amplifier, voltage promotion and voltage

regulated power source, high stability bandgap, auto measurement switch and function control circuit,

buzzer driver circuit, clock oscillator circuit, Backlight display control circuit, LCD display driver circuit and

so on.

Due to FS9721B is embedded microprocessor so that it can control the logic function during passing

I/O. Measurement functions can be combined differently by using MEA1〜MEA4 pins code; through the

setting to the code can build the fully auto measurement meter. There are Range, Select, Hold/BLCTR, Rel,

Hz/Duty, RS232 and Reset keys so that you can fulfil measurement selection, functions switch, data hold,

Backlight display, relative value, frequency and duty cycle measurement, data transmission, reset and so

on functions through these keys.

FS9721B has series data output function. User can connect the meter to computer to record, analysis,

process and print the measured data.

With regard to the auto power off function, when there is no action within 30 minutes on the switch or

keys of the meter, the system will enter the sleep mode automatically to save the power. In the process of

using the meter, if it is not necessary to power off automatically, the function can also be cancelled in use.

FS9721B is manufacted by large intergrated circuit technology that has rised hugely the reliability of

product and made the design be easy and the volume be small; the system takes low power voltage so as

to be low power consumption and is convenient to use the power supply of battery, especially is proper for

the use on the palm mode meter.

FS9721B is a multi-measurement AC/DC converter that embedded the microprocessor. Only less

addition of external components, you can constitute a high accuracy, mult-function and low cost meter.

2

Features

Maximum Display: 2400 (3⅔ digits).

Converter Rate: 3 times/sec.

The Negative Instruction: Auto.

Power Voltage Range: 2.4V〜3.6V.

Chip Power Consumption: ≤6mW.

Low Battery Warning: About 2.4 V.

Buzzer Driver Circuit (Frequency is about 2.7kHz).

RS232 Serial Data Output.

Embedded OPAMP for DC/AC switch.

Function Keys: Range, Select, Hold/BLCTR, Rel, Hz/Duty, RS232, Reset.

Unit Symbol and Backlight Display.

Auto Power-off.

3

Measurable Modes

DC Voltage: 240.0mV, 2.400V, 24.00V, 240.0V, 1000V.

AC Voltage: 240.0mV, 2.400V, 24.00V, 240.0V, 1000V.

DC: 240.0μA/ 2400μA,24.00mA/ 240.0mA,2.400A, 10.00A.

AC: 240.0μA/ 2400μA,24.00mA/ 240.0mA,2.400A, 10.00A.

Resistance: 240.0Ω,2.400kΩ,24.00kΩ,240.0kΩ,2.400MΩ,24.00MΩ.

Capacitance: 2.500nF,25.00nF,250.0nF,2.500μF,25.00μF.

Frequency: 5.000Hz, 50.00Hz, 500.0Hz, 5.000kHz, 50.00kHz, 500.0kHz, 5.000MHz

Duty Cycle: 0.1%〜99.9%.

Diode: 0V〜1.5 V.

Short Circuit Testing: Sound when lower than 50Ω.