P6230: Difference between revisions

From TekWiki
Jump to navigation Jump to search
No edit summary
mNo edit summary
 
(13 intermediate revisions by 2 users not shown)
Line 1: Line 1:
[[File:P6230-6.jpg|thumb|right|300px|P6230/P6231 probe tip]]
{{Probe Sidebar
[[File:P6230-1.jpg|thumb|right|300px|P6230 termination box]]
|manufacturer=Tektronix
|model=P6230
|summary=1.5 GHz, 450:50 Ω passive probe
|image=P6230-6.jpg
|caption=Tektronix P6230
|for=50 Ω scope inputs
|introduced=1984
|discontinued=(?)
|manuals=
* [[Media:070-4211-00.pdf|P6230 Operator manual]] (OCR)
* [[Media:070-6027-00.pdf|P6231 Instruction manual]] (OCR)
}}
[[File:P6230-1.jpg|thumb|right|250px|P6230 termination box]]
The '''Tektronix P6230''' and '''P6231''' are passive ×10 (450:50 Ω) probes with 1.5 GHz bandwidth and DC offset capability, intended to minimize DC probe-loading effect when used on logic circuits.
The '''Tektronix P6230''' and '''P6231''' are passive ×10 (450:50 Ω) probes with 1.5 GHz bandwidth and DC offset capability, intended to minimize DC probe-loading effect when used on logic circuits.


The '''P6230''' has an offset control potentiometer in the termination box and connects to the scope, e.g. [[7000 series scopes]], through a [[BNC connector]] with ×10 readout pin.  It can be powered from 7000 series mainframes having [[LEMO S-series connector]]s for probe power, or compatible units such as the [[1101]].
The '''P6230''' has an offset control potentiometer in the termination box and connects to the scope, e.g. [[7000 series scopes]], through a [[BNC connector]] with ×10 readout pin.  It can be powered from 7000 series mainframes having [[LEMO S-series connector]]s for probe power, or compatible units such as the [[1101]].


The '''P6231''' and is intended for 11000 series plugins such as the [[11A32]].  Offset control and power are provided by the scope mainframe through a [[Tekprobe BNC connector]].
The '''P6231''' is a TekProbe Level 2 probe intended for 11000 series plugins such as the [[11A32]] or [[11A71]].  Offset control and power are provided by the scope mainframe through a [[Tekprobe BNC connector]].


The P6230/6231 shares accessories with many other Tektronix [[subminiature modular probes]] although the input hybrid is unique.  Tip color is yellow, connector end color is blue, part number [[206-0279-00]].  Its end to end resistance is 400 Ω.
The P6230/6231 shares accessories with many other Tektronix [[subminiature modular probes]] although the input hybrid is unique.  Tip color is yellow, connector end color is blue, part number [[206-0279-00]].  Its end to end resistance is 400 Ω.
Line 15: Line 27:
{{Spec | Input Impedance | 450 Ω // 1.3 pF  (1.6 pF guaranteed) }}
{{Spec | Input Impedance | 450 Ω // 1.3 pF  (1.6 pF guaranteed) }}
{{Spec | Signal delay    | 8.7 ± 0.1 ns    }}
{{Spec | Signal delay    | 8.7 ± 0.1 ns    }}
{{Spec | DC Offset range | -5 V ≤ (V<sub>signal</sub> + V<sub>offset</sub>) ≤ +5 V }}
{{Spec | DC offset      | −5 V ≤ (V<sub>signal</sub> + V<sub>offset</sub>) ≤ +5 V }}
{{Spec | Features |  
{{Spec | Features |  
* Readout Pin  
* Readout Pin  
Line 28: Line 40:
<blockquote>
<blockquote>
The P6230 acts as a standard 500 Ω passive voltage probe with the additional capability of having an adjustable tip "nulling voltage." This feature reduces the dc-loading effects on the probe when it is used to measure signals whose mid-voltage value is other than zero volts, or in circuits where the termination impedance is returned to other than ground level. The Input Bias/Offset Voltage may be adjusted so that at a particular test-signal voltage both ends of the probe input-resistor are at equal potentials and no current is flowing through the resistor.  
The P6230 acts as a standard 500 Ω passive voltage probe with the additional capability of having an adjustable tip "nulling voltage." This feature reduces the dc-loading effects on the probe when it is used to measure signals whose mid-voltage value is other than zero volts, or in circuits where the termination impedance is returned to other than ground level. The Input Bias/Offset Voltage may be adjusted so that at a particular test-signal voltage both ends of the probe input-resistor are at equal potentials and no current is flowing through the resistor.  
</blockquote>
 
<blockquote>
ECL logic is most commonly operated from a −5.2 V supply with V<sub>CC</sub> connected to ground. The output of an ECL gate is the emitter of an NPN emitter follower stage. The output is pulled down to a negative supply (about −2 V) with an external resistor (50 Ω to 100 Ω). Since speed is a major consideration in ECL designs, the interconnections between gates are often transmission lines, and the pull-down resistor doubles as a line termination.  
ECL logic is most commonly operated from a -5.2 V supply with Vcc connected to ground. The output of an ECL gate is the emitter of an NPN emitter follower stage. The output is pulled down to a negative supply (about -2 V) with an external resistor (50 Ω to 100 Ω). Since speed is a major consideration in ECL designs, the interconnections between gates are often transmission lines, and the pull-down resistor doubles as a line termination.  
 
</blockquote>
<blockquote>
If a standard 500 Ω, 10× probe without the input Bias/Offset feature were used to examine an ECL output, the probe's 500 Ω resistance to ground would form a voltage divider with the gate's output-termination resistor. This divider can cause distortion of the output signal levels, shift the DC operation point of the output transistor, and reduce the gate's noise margin.  
If a standard 500 Ω, 10× probe without the input Bias/Offset feature were used to examine an ECL output, the probe's 500 Ω resistance to ground would form a voltage divider with the gate's output-termination resistor. This divider can cause distortion of the output signal levels, shift the DC operation point of the output transistor, and reduce the gate's noise margin.  
</blockquote>
 
<blockquote>
The DC-load nulling capability of the P6230 helps to solve this problem. By adjusting the Input Bias/Offset Voltage to the ECL low level or to the termination voltage, the only effect of the probe resistance will be a small decrease in the ECL output-termination resistance. The effect of the probe on output voltage levels is negligible.  
The DC-load nulling capability of the P6230 helps to solve this problem. By adjusting the Input Bias/Offset Voltage to the ECL low level or to the termination voltage, the only effect of the probe resistance will be a small decrease in the ECL output-termination resistance. The effect of the probe on output voltage levels is negligible.  
</blockquote>
</blockquote>
Line 41: Line 50:
==Links==
==Links==
* [http://www.barrytech.com/tektronix/probes/tekp6230.html P6230] / [http://www.barrytech.com/tektronix/probes/tekp6230.html P6231] @ barrytech.com (incorrectly described as active probe)
* [http://www.barrytech.com/tektronix/probes/tekp6230.html P6230] / [http://www.barrytech.com/tektronix/probes/tekp6230.html P6231] @ barrytech.com (incorrectly described as active probe)
==Manuals==
* [http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK%20P6230%20OPS.pdf P6230 Operator's manual] (PDF, 155KB)
* [[Media:070-6027-00.pdf | P6231 Instructions manual]] (PDF, OCR, 740KB)
* [http://w140.com/tekp6203-p62204-p62205-p6217-p6231.pdf Tektronix P6203 P6204 P6205 P6217 P6231 Catalog Specs (PDF)]


==Prices==
==Prices==
Line 52: Line 56:
! Year
! Year
!   1984  
!   1984  
!   1985  
!   1987  
!   1987  
!   1989  
!   1989  
Line 60: Line 63:
! P6230 Catalog price
! P6230 Catalog price
|align=right|  $385
|align=right|  $385
|align=right|  $395
|align=right|  $395
|align=right|  $395
|align=right|  $420
|align=right|  $420
Line 66: Line 68:
|align=right|  –
|align=right|  –
|-
|-
! 2015 value
! In 2023 Dollars
|align=right|  $880
|align=right|  $1,100
|align=right|  $870
|align=right|  $1,100
|align=right|  $825
|align=right|  $1,000
|align=right|  $800
|align=right|  $1,200
|align=right|  $915
|align=right|  –
|align=right|  –
|-
|-
! P6231 Catalog price
! P6231 Catalog price
|align=right|  –
|align=right|  –
|align=right|  –
|align=right|  $410
|align=right|  $410
Line 82: Line 82:
|align=right|  $799
|align=right|  $799
|-
|-
! 2015 value
! In 2023 Dollars
|align=right|  –
|align=right|  –
|align=right|  –
|align=right|  $860
|align=right|  $1,200
|align=right|  $780
|align=right|  $1,000
|align=right|  $915
|align=right|  $1,200
|align=right|  $1,240
|align=right|  $1,600
|}
|}
   
   
Line 116: Line 115:
P6230-rt2.jpg | P6230 Rise time without ground lead: 9.2 * 20 ps = 184 ps (equiv. to 1.9 GHz bandwidth)
P6230-rt2.jpg | P6230 Rise time without ground lead: 9.2 * 20 ps = 184 ps (equiv. to 1.9 GHz bandwidth)
P6230-rt3.jpg | Effect of using the "low inductance" ground lead - rise time 400 ps, bandwidth 875 MHz
P6230-rt3.jpg | Effect of using the "low inductance" ground lead - rise time 400 ps, bandwidth 875 MHz
P6230-rt4.jpg | Using the 250 mm alligator ground lead - severe pulse distortion, rise time ~3 ns (115 MHz)!
P6230-rt4.jpg | Using the 250 mm (9.8") alligator ground lead - severe pulse distortion, rise time ~3 ns (115 MHz)!
P6230-bw.jpg  | Bandwidth vs. grounding, from manual
P6230-bw.jpg  | Bandwidth vs. grounding, from manual
</gallery>
</gallery>
Line 122: Line 121:


[[Category:Subminiature modular probes]]
[[Category:Subminiature modular probes]]
[[Category:50 Ohm Oscilloscope Probes]]
[[Category:50 Ω Oscilloscope probes]]
[[Category:Introduced in 1984]]
[[Category:Tekprobe BNC]]

Latest revision as of 03:47, 12 February 2024

Tektronix P6230
1.5 GHz, 450:50 Ω passive probe
Tektronix P6230

Compatible with 50 Ω scope inputs

Produced from 1984 to (?)

Manuals


Manuals – Specifications – Links – Pictures
P6230 termination box

The Tektronix P6230 and P6231 are passive ×10 (450:50 Ω) probes with 1.5 GHz bandwidth and DC offset capability, intended to minimize DC probe-loading effect when used on logic circuits.

The P6230 has an offset control potentiometer in the termination box and connects to the scope, e.g. 7000 series scopes, through a BNC connector with ×10 readout pin. It can be powered from 7000 series mainframes having LEMO S-series connectors for probe power, or compatible units such as the 1101.

The P6231 is a TekProbe Level 2 probe intended for 11000 series plugins such as the 11A32 or 11A71. Offset control and power are provided by the scope mainframe through a Tekprobe BNC connector.

The P6230/6231 shares accessories with many other Tektronix subminiature modular probes although the input hybrid is unique. Tip color is yellow, connector end color is blue, part number 206-0279-00. Its end to end resistance is 400 Ω.

Key Specifications

Bandwidth DC to ≥ 1.5 GHz
Rise time ≤ 230 ps
Attenuation 10×
Input Impedance 450 Ω // 1.3 pF (1.6 pF guaranteed)
Signal delay 8.7 ± 0.1 ns
DC offset −5 V ≤ (Vsignal + Voffset) ≤ +5 V
Features
  • Readout Pin
  • Switchable 50 Ω termination

Internals

The P6230/6231 probes are sometimes described as FET probes or active probes, however, as the circuit diagram clearly shows, this is not correct. After the 400 Ω input hybrid, the AC component of the input signal is connected directly to the scope input through a 1 μF capacitor, then terminated in 50 Ω either in the scope input or the switchable terminator. The active circuit in the P623x, a standard NE5532 dual opamp, has the function of restoring and offsetting the input signal's low-frequency and DC components. This approach is similar to the feed-beside technique used in the 7104 scope and 7A29 amplifier.

Tek explains the raison d'être for the P6230/P6231 thus:

The P6230 acts as a standard 500 Ω passive voltage probe with the additional capability of having an adjustable tip "nulling voltage." This feature reduces the dc-loading effects on the probe when it is used to measure signals whose mid-voltage value is other than zero volts, or in circuits where the termination impedance is returned to other than ground level. The Input Bias/Offset Voltage may be adjusted so that at a particular test-signal voltage both ends of the probe input-resistor are at equal potentials and no current is flowing through the resistor.

ECL logic is most commonly operated from a −5.2 V supply with VCC connected to ground. The output of an ECL gate is the emitter of an NPN emitter follower stage. The output is pulled down to a negative supply (about −2 V) with an external resistor (50 Ω to 100 Ω). Since speed is a major consideration in ECL designs, the interconnections between gates are often transmission lines, and the pull-down resistor doubles as a line termination.

If a standard 500 Ω, 10× probe without the input Bias/Offset feature were used to examine an ECL output, the probe's 500 Ω resistance to ground would form a voltage divider with the gate's output-termination resistor. This divider can cause distortion of the output signal levels, shift the DC operation point of the output transistor, and reduce the gate's noise margin.

The DC-load nulling capability of the P6230 helps to solve this problem. By adjusting the Input Bias/Offset Voltage to the ECL low level or to the termination voltage, the only effect of the probe resistance will be a small decrease in the ECL output-termination resistance. The effect of the probe on output voltage levels is negligible.

Links

  • P6230 / P6231 @ barrytech.com (incorrectly described as active probe)

Prices

Year   1984     1987     1989     1991     1995  
P6230 Catalog price $385 $395 $420 $525
In 2023 Dollars $1,100 $1,100 $1,000 $1,200
P6231 Catalog price $410 $410 $525 $799
In 2023 Dollars $1,200 $1,000 $1,200 $1,600

Pictures

Measurements