Salas SSLV1.3 UltraBiB shunt regulator

[Salas]

LM4562 says typical Iq per channel 5mA and OPA2134 says typical Iq per channel 4mA.
Are you using five whole dual chips per channel or five sections per channel?

 

[damiangt3]

4 whole chips per channel, 1 HF, 2 MF, 1 LF in 24dB LR configuration and a input buffer using half of one.

 

[Salas]

So 45mA Iq per channel per rail if with LM4562s. Any no less than 150mA CCS setting per reg should cover the situation. Ensures 100mA spare for robust reg Zout.

 

[Salas]

3.3Ω rset is fine, gives ample margin for swings too.

 

[Abx74]

Hi Salas,


can I make my own pcb using schematic in post #1 or is there a newer version ?


Thanks


Damien

 

[Salas]

Hi

There is no newer version

 

[Abx74]

Thanks and thanks again for sharing !

 

[Oneminde]

The plan is to use the UBiB to power an OP-Amp (AD825). Maximum current draw according to the sheet @ 15V is 7.2mA. 15*0.0072A = 0.1W. In regards to this I am struggling a bit to select resistors. I would like to use SMT which is usually caped at 250mW.

Is a 250mW resistor too small fo a headroom ?

 

[Oneminde]

On another note, Looking at the positive version, Q1 calls for BC327 which is PNP but sch. symbol show an NPN and he negative version use BC337 for Q1 which is an NPN but the sch. symbol show an PNP.

So, what is correct, the component or the sch. symbol ?

- EDIT -
Never mind, its the orientation of the component and no clear indication of emitter, base an collector... I will design the schematic locally and check with the forum for confirmation

 

[Salas]

The plan is to use the UBiB to power an OP-Amp (AD825). Maximum current draw according to the sheet @ 15V is 7.2mA. 15*0.0072A = 0.1W. In regards to this I am struggling a bit to select resistors. I would like to use SMT which is usually caped at 250mW.

Is a 250mW resistor too small fo a headroom ?

Select R1 5.6 Ohm for circa 100mA+ CCS. Dissipation of R1 will be about 60mW.

 

[Oneminde]

Thank you, then my collection of BC860/850 transistors can be used

 

[Salas]

On another note, Looking at the positive version, Q1 calls for BC327 which is PNP but sch. symbol show an NPN and he negative version use BC337 for Q1 which is an NPN but the sch. symbol show an PNP.

So, what is correct, the component or the sch. symbol ?

- EDIT -
Never mind, its the orientation of the component and no clear indication of emitter, base an collector... I will design the schematic locally and check with the forum for confirmation

The published schematics are 100% correct. Follow them without hesitation. There are clear and adequate emitter arrows also there. If you will analyze beyond PSUs output polarities you will understand why those semiconductors polarities work that way inside the PSUs.

 

[Oneminde]

As long as I know if it is PNP or NPN I'm okay.

 

[Salas]

All you need knowing to build successfully.

 

[Salas]

Thank you, then my collection of BC860/850 transistors can be used

Except M1 & M2 MOSFETS no small transistor or JFET suffers from noticeable dissipation in this circuit

 

[Oneminde]

Correct, M1 will be FQP3P20 & M2 will be IRF830A.

 

[Salas]

530

 

[Oneminde]

IRF530PBF is available with slightly less Rds at 160mOhm vs 180mOhm for the normal 530.
STP25N10F7 looks nice: 100V, 25A, 35mOhm and Qg = 14nC vs 26nC for the 530PBF.

STP25N10F7 STMicroelectronics | Mouser Sverige

 

[Salas]

Moving away from the listed semiconductors main number types is not recommended. Especially for parasitic capacitance specs of M1 M2 Q2 Q3. Oscillations may occur or not.

 

[Oneminde]

Understood