Finished LPS-50-MKI 50VA Linear Power supply
Works voltage: AC110V or AC220V for choose.
Output voltage:
we can provide following several kinds for choose:
1: 5V @4.1A
2: 9V @3.3A
3: 12V @2.7A
4: 15V @2A
5: 18V @2.0A
6: 19V @2.0A
7: 24V @1.6A
also can accept custom-make other voltage.
front color default silver ( can provide black front)
Transformer power: 50VA
Output DC cable plug type: default 5.5*2.1mm (Polarity: Internal + / outside - )
weight: about 3kg/set
External dimensions Size:150mm*270mm*70mm
With output voltage display.(display color default is Red, can provide Blue, Green for choose)
Package include: Finished linear power supply X1
1.2M Output DC cable 5.5*2.1mm X 1
(default is not include AC input cable)
Technical highlights
All-discrete topology.
Single-pass, series regulator design.
No IC (integrated circuits) are used. This allows complete design control over all operating points and parameters for superior performance.
Low noise, high PSRR
A constant-current source feeds a zener diode as a stable voltage reference. A low-pass filter (with a corner frequency of 1.6Hz) prevents zener noise from being introduced into the error amplifier. This is an effective yet lower-cost alternative to expensive voltage reference ICs. The low-pass filter also provides a soft-start characteristic.
The output noise (unloaded) is less than 13µV at 24VDC output (measured using a Tangent LNMP (low-noise measurement preamplifier) and a Fluke 187 50000-count DMM in ACmV mode). The output noise is even less when the output voltage is lower. This is much better than the noise of an IC regulator based PSU tested under identical conditions.
The error amplifier is a discrete implementation of an opamp with a high open-loop gain of 102.5dB. The voltage supply to the error amplifier is isolated with capacitance multipliers to boost its PSRR (power supply rejection ratio). This greatly improves the line regulation performance of the PSU.
A long-tailed pair differential amplifier with current mirror and constant current source forms the first stage of the error amplifier. The second stage is the voltage amplification stage (VAS), also with constant current source load. The 3rd stage is comprised of the power MOSFET output devices configured as a source follower.
High-current MOSFET pass transistors
Two paralleled high-current, highly reliable MOSFETs (rated at 18A each) serve as the "pass" transistor.
The high current rating provides a very high safety headroom against overcurrent damage.
The use of paralleled MOSFETs divides the heat dissipation, simplifying thermal management. Onboard heatsinks can be used which would allow the σ11 to supply up to 1A continuous (with much higher peak currents). More sustained currents are possible by using larger, offboard heatsinks.
The negative temperature coefficient of MOSFETs prevents damaging thermal-runaway conditions that may plague conventional BJT devices.
No current-limiting.