New JRC has launched a new Analog Front End (AFE) "NJU9103" with built-in PGA which can set a gain of up to 512. The NJU9103 is suitable for pressure gauges and flow meters and entered mass production.
General Description
Recently, not only is the wide measuring range required for sensor devices such as pressure gauges and flow meters, but the small-size, lightweight and thinness are also needed for measuring instrument.
The NJU9103 has built-in PGAs (Programmable Gain Amplifier) which set a gain of up to 512, therefore the measuring range can be wide. You can adjust optimal gain for various measuring range of sensors.
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| Equivalent Circuit Block Diagram. |
The NJU9103 has a built-in 16 bit ΔΣA/D converter and can input two differential signals, single end signal and pseudo differential signal.
The NJU9103 strictly selected the necessary function for measuring instrument and successfully used the smallest 8 pin package in the industry.
You can easily adjust parameters from MCU by SPI communication. Therefore the NJU9103 plays an important role for shortening development cycle, setting new series, and achieving the small-size, lightweight and thinness.
Features
1. Built-in PGA can set a gain of up to 512
Currently the built-in PGA in AFE as mainstream sets a gain of up to only 128. But the NJU9103 has 2 buit-in PGAs setting gain to 128 and 4. Combining them can provide the gain of up to 512. You can adjust optimal gain for various measuring range of sensors.
2. Built-in D-A converter (DAC) for calibrating offset voltage of sensor
If it has error of offset voltage in the output of sensor, when PGA gain is large, the offset voltage is also amplified. So the AFE may exceed the signal processing capability range.
The built-in DAC in the NJU9103 can generate reversed voltage to offset voltage of sensor.
The reversed voltage adds to offset voltage, so reduce the offset voltage. Even if the PGA gain is large, the AFE will not be the case of exceeding the signal processing capability range.
3. Small-sized packaging can reduce the area of PCB
The NJU9103 strictly selected the number of connecting sensors and the necessary function such as externally adjusted temperature calibration, and put them into one 8pin package. Therefore the mounting area can be shrunk by the NJU9103 and save the area of PCB. We have also prepared a kind of lead type SSOP package and another kind of no-lead type ESON8-V1 package. You can select suitable type for various uses.
The NJU9103 makes contributions for small-size, lightweight and thinness of measuring instrument.
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| The ESON8-V1 Package. | The SSOP8 Package. |
Evaluation Kit
We have prepared the evaluation kit for confirming AFE operating state easily. (Evaluation Board and Software).
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| The Evaluation Board for NJU9103 AFE. |
Characteristics
- ADC resolution: 16 bit (No missing codes)
- Conversion rate: 0.814 ksps to 6.51 ksps
- Input mode: Differential/Single-end/Pseudo differential
- PGA: Gain of 1 to 512
- Calibration function: Calibrating offset/gain error
- Conversion mode: Single/Continuous
- Interface: SPI (Serial Peripheral Interface)
- Package:
- ESON8-V1 (2.3 mm × 2.3 mm)
- (3.5 mm × 6.4 mm)
Application
- Pressure gauge
- Flow meter
- Temperature controller
- Programmable logic controller
- Digital panel meter
