PDVS 2 Mini v2 - ADR1399

PDVS 2 Mini v2 - ADR1399

Precision Digital Voltage Source. The well known and proven PDVS 2 Mini with further incremental improvements for v2.

For more on the background and measurements, see the v2 development blog posts.

Firmware v2.26 Improvements

Firmware v2.26 is a substantial update while keeping the normal operation of the PDVS 2 Mini unchanged. The update includes:

•  Optional advanced firmware features:
  • Temperature Coefficient Compensation (TCC), using the internal temperature sensor to compensate for temperature-related output drift.
  • Optional extended low-end output range down to –0.01000 V in 10 µV steps.
    
• Reworked SCPI-style serial command interface:
  • More consistent command structure for remote control and system queries.
  • Extended command coverage for settings, calibration values, runtime, internal temperature, TCC parameters, and other system information.
  • Supported baud rates from 4800 to 230400, fully compatible with the IUSL.
    
    
• Reduced current draw:
  • Firmware restructuring significantly reduces the 3.3 V logic rail current.
  • In normal operation with the serial interface disabled, total battery current draw is reduced by over 15%, extending runtime.

The optional advanced features are user-activated and are not part of the standard factory calibration unless explicitly stated. For more detail, see the firmware enhancement blog post.

Hardware v2 Improvements

• Careful changes to the analogue section:
  • Improved step response with faster risetime and elimination of ~25% overshoot
    
  •  Lower noise, both in low-frequency (0.1–10 Hz) and wideband (10 Hz–10 kHz) ranges — roughly half of v1 levels
  • Improved temperature coefficient to below -0.2ppm/K for units tested
    
  • All units now equipped with the ADR1399 reference and gold plated output jacks

• Further updates and enhancements:
  • Integration of the charging PCB onto the main PCB. Changed DC connector size to standard 2.5x5.5 mm and not mounted recessed anymore so all styles of connectors can be used (instead of specific slim ones for v1 units)
  • New microcontroller at faster clock speed and large parts of firmware rewritten for snappier feel and more stable serial connection (now up to 230400 baud, fully compatible with the IUSL)
  • Combination of power and ok buttons and software changes to avoid accidential turn offs

Functions and Features: 

• True 0 to 10.22222 V DC user adjustable output in 10 µV steps
• Integrated digital temperature sensor for internal temperature readout with 0.1°C resolution, internal and ambient temperature noted on calibration certificate
• Fully remote controllable via serial connection, incl. output of internal temperature and further parameters
  
• All digital calibration, full recalibration and adjustment possible by user
• Integrated battery management IC to charge 9 V Li-Ion batteries, incl. battery voltage monitor, low voltage warning, autoshutdown, charging status and battery reverse polarity protection

Specification Summary

• Voltage reference: ADR1399
• Voltage range: 0.00000 V to 10.22222 V in 10 µV steps; optional user-activated range down to –0.01000 V
  
• Load = 10mA max; internally protected against indefinite short circuiting of output
• Accuracy = Within 50 µV. Typically 0.0005% at 10 V output
• Stability = 0.00005 V variation worst case. Orientation of the unit may affect output (calibrated horizontally), as will powering from external DC source
• Temperature coefficient (whole unit) = Typically < 2 ppm across a 10K temperature change; optional user-activated TCC function can compensate for temperature-related output drift.
  
• Stabilization time: around 30 minutes depending on ambient temperature, coming off battery charge and last use
  
• Power (batteries) = Two Lithium-Ion re-chargeable 9V PP3 batteries (Not supplied, 600mAh batteries recommended)
• Charging (external power)  = 18 to 20 V DC. For battery charging, 250 mA max. charge current. Uses a standard 2.5x5.5mm barrel jack connector; charging cable supplied.
• Battery consumption = ~100 mA at power up, reducing to ~43 mA when reference heater has stabilized.
• Battery quiescent current (unit switched off) ~4 µA.
• Battery = Approx. 14 hours typical continuous operation with recommended EBL 6F22 Li-ion 600 mAh batteries . Any rechargeable Lithium-Ion 6F22 batteries will do, ranging from 500 mAh to 1000 mAh
• Dimensions = 105 x 65x 52 mm

Included Items

• PDVS 2 Mini v2
• Charging cable with barrel plug and unterminated end
• Certificate of calibration