The GM-235A / B are a complete digital voltmeter module in a very compact package incorporating a dual-slope analog-to-digital converter, a 100mV reference with 200mV full scale input sensitivity-A version, and 1V reference with 2V full scale input sensitivity-B version. The use of large-sized LCD makes the module easily readable from distance away. The single 5VDC operation enables the module to be easily operated with the most commonly used system power source. Auto-zeroing is provided by the circuit itself, so no zero adjustment is required. Automatic input polarity indication and over-range indication by displaying 1 --- are all available. The GM-235A/B and GM-335A/B are pin to pin compatibility (interchangeability) allows the user to select the display type of module (LCD or LED) freely without modifying the system circuitry.
Specifications
- Operating voltage: 5V +/- 5%
- Operation Temperature: 0 to 50 Celsius (32 to 122 Fahrenheit)
- Storage temperature: -10 to 70 Celsius (14 to 158 Fahrenheit)
- Pin 1:
- Symbol: V+
- Description: +5V power supply
- Pin 2:
- Symbol: GND
- Description: Ground
- Pin 3:
- Symbol: IN HI
- Description: 200mV or 2V full scale input, "IN HI" is lower than "IN HI", display will show negative.
- Pin 4:
- Symbol: IN LO
- Description: 200mV or 2V full scale input, "IN HI" is lower than "IN HI", display will show negative
- Pin 5:
- Symbol: DP1
- Description: Decimal point select. The decimal point will be shown if connected to DP.com and will be off if kept floating.
- Pin 6:
- Symbol: DP2
- Description: Decimal point select. The decimal point will be shown if connected to DP.com and will be off if kept floating.
- Pin 7:
- Symbol: DP3
- Description: Decimal point select. The decimal point will be shown if connected to DP.com and will be off if kept floating.
- Pin 8:
- Symbol: DP1.com
- Description: Decimal point select. The decimal point will be shown if connected to DP.com and will be off if kept floating.
- Model: GM-235A
- Full scale: 200mV
- Accuracy: 0.1% +/- 1dgt
- Input format: different or single-ended
- Model: GM-235B
- Full scale: 2V
- Accuracy: 0.1% +/- 1dgt
- Input format: different or single-ended
Features
- Single 5VDC operation
- Decimal point selectable
- Self-mountable
- High input impedance > 100 M ohm
- 200mV and 2V full scale input sensitivity (A and B version)
- Pin to pin compatible with GM-335A/B
- Crystal-controlled oscillation for excellent noise rejection
- 0.4 inch (10.16mm) digit height
- Single-ended or differential input format
- Applications:
- Digital power supply
- Digital measuring equipment
- Digital strain gauge instrument
| Characteristics | MIN | TYP | MAX | UNT |
|---|---|---|---|---|
| Power supply voltage | 4.75 | 5 | 5.25 | V |
| Power supply current | N/A | 3 | 5 | mA |
| Sampling rate | N/A | 2.5 | N/A | Reading/sec. |
| Accuracy | N/A | 0.1% +/- 1dgt | N/A | % +/- digits |
| Input impedance | 100 | N/A | N/A | M ohm |
| Input leakage current | N/A | 1 | 10 | PA |
| Temperature coefficient | N/A | 100 | N/A | PPM/Celsius |
Main Products
digital panel meter