Overview
The DAC7750IRHAR from Texas Instruments is a 12-bit, single-channel, programmable current output Digital-to-Analog Converter (DAC) designed for industrial process-control applications. This device is part of the DACx750 series, which includes both 12-bit and 16-bit DACs. The DAC7750 is known for its precision, reliability, and versatility, making it suitable for a wide range of industrial control systems.
The device offers multiple current output ranges: 0 mA to 24 mA, 0 mA to 20 mA, and 4 mA to 20 mA, with a typical total unadjusted error (TUE) of ±0.1% Full Scale Range (FSR). It also features an internal 5-V reference with a maximum drift of 10 ppm/°C and an internal 4.6-V power-supply output.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Resolution | 12 bits | |
| Current Output Ranges | 0 mA to 24 mA, 0 mA to 20 mA, 4 mA to 20 mA | |
| Total Unadjusted Error (TUE) | ±0.1% FSR | |
| Differential Nonlinearity (DNL) | ±1 LSB maximum | |
| Maximum Loop Compliance Voltage | AVDD – 2 V | |
| Internal Reference | 5 V, 10 ppm/°C (maximum) | |
| Internal Power-Supply Output | 4.6 V | |
| Operating Temperature Range | –40°C to +125°C | |
| Package Options | 40-pin VQFN, 24-pin HTSSOP | |
| Supply Voltage Range | 10 V to 36 V |
Key Features
- CRC frame error check for data integrity
- Watchdog timer for system reliability
- Thermal alarm and open-circuit alarm for fault detection
- Pins to monitor output current through an internal precision resistor
- On-chip fault alarm and user-calibration for offset and gain
- Programmable output slew rate
- Ability to superimpose an external HART signal on the current output
- Power-on-reset function to ensure a known state at startup
- CLR pin to set the current output to the low end of the range if enabled
Applications
- Analog output modules
- CPU (PLC controllers)
- Flow transmitters
- Other sensor transmitters
- Actuators
- Process analytics (pH, gas, concentration, force, and humidity)
Q & A
- What are the current output ranges of the DAC7750?
The DAC7750 offers current output ranges of 0 mA to 24 mA, 0 mA to 20 mA, and 4 mA to 20 mA.
- What is the typical total unadjusted error (TUE) of the DAC7750?
The typical TUE is ±0.1% Full Scale Range (FSR).
- What is the maximum drift of the internal 5-V reference?
The maximum drift is 10 ppm/°C.
- What are the package options for the DAC7750?
The device is available in 40-pin VQFN and 24-pin HTSSOP packages.
- What is the operating temperature range of the DAC7750?
The operating temperature range is –40°C to +125°C.
- Does the DAC7750 support HART modulation?
Yes, it can superimpose an external HART signal on the current output.
- What is the purpose of the watchdog timer in the DAC7750?
The watchdog timer is a reliability feature that ensures system integrity by monitoring for timeouts and other critical conditions.
- How can the output current be monitored in the DAC7750?
The output current can be monitored by accessing an internal precision resistor through the R3-SENSE pin.
- What is the function of the CLR pin in the DAC7750?
The CLR pin sets the current output to the low end of the range if the output is enabled.
- Can the DAC7750 be calibrated for offset and gain?
Yes, the device supports user-calibration for offset and gain through the zero and gain registers.
