Description
This board is a variation of the PWM3B with an improved linearity, low output impedance and low ripple thanks to the use of a -12dB/Octave low pass active filter in the output stage.
Most small micro-controllers do not have real D/A converters to produce analog outputs, instead they provide PWM signals that can be converted to analog values using an LP filter. This approach is good enough to generate 0-3.3V or 0-5V analog outputs (depending on the logic level of the controller) to control small powered devices, but is not suitable to interface with high power systems, such as VFDs or Servo controllers for electric motors.
This board provides the adequate isolation and level conversion to control the three separate actuators safely and precisely.
The board requires a 24Vdc power supply and delivers and output level adjustable between 5V and 12V at full scale, making it directly compatible with most comercial drives. Alternatively the power supply can be reduced to 10V (i.e. using the “wetting” voltage provided by most commercial VFD) by limiting the output voltage to 6 V.
Each channel is totally independent and optically isolated from the others and the controller.
The board is fitted with standard 0.2″ screw terminals and can be delivered with or without enclosure. The optional enclosure can be mounted in a standard DIN rail for easy integration in electrical control cabinets.
Specifications
- Number of channels: 3
- PWM input: TTL level. Max frequency 1 KHz
- Output voltage: Adjustable 0 to 5..12V
- Output Current: 30 mA max (per channel)
- Output filter: 16Hz 2 pole
- Linearity: Better than 0.5% FSD
- Isolation: Min. 500 Vac
- Power voltage: Nominal 24 Vdc (Acceptable range 17 to 30Vdc)
- Power current: 12 mA/channel (Excluding output current)
- Dimensions: 3.400 x 2.700 in. (87 x 69 mm)
- Weight: 1.7 oz (0.055 Kg)
Usage
Each channel is totally independent, therefore they can be connected to different controllers (if required). The same applies for the outputs.
Documentation
- Instructions: PWM3TP Instructions
Enclosures
- Bud Industries DMB4772
- Digikey 3DMB4772
- Mouser DMB4772
- Newark DMB-4772
- Velleman GD4MG
- CamdenBox CNMB/4/kit
Lead time
Back orders ship usually in 2 weeks.