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PZ3 Tech Notes

Noisy channel on PZ amplifier at 50kHz sampling rate

TN0903

Product: PZ2, PZ3
Version: Serial numbers PZ2 < 4000, PZ3 < 2000
Date Added: 2012-08-03

Issue

In some cases, user may see low amplitude high frequency noise on the 15th channel of a PZ2 amplifier board (8th channel of a PZ3 board) when running at 50kHz sampling rate.

Solution

It is recommended that users who are operating at 50kHz contact TDT to request an RMA.

Building a custom headstage to use with SI, PZ, IZ, or ACO

TN0896

Product: PZA (SI), PZD (SI), IZV (SI), PZ5, PZ2, PZ3, IZ2, IZ2H, IZ2M, IZ2MH, ACO32, ACO64
Version: All
Date Added: 2012-02-08

Issue

This tech note provides the information needed to wire a custom or third-party headstage to TDT amplifiers, stimulus isolators, and commutators.

Solution

The PZA (SI), IZV (SI), PZ5 analog, PZ2, PZ3, IZ2, IZ2H, IZ2M, IZ2MH, ACO32, and ACO64 all use the same female mini-DB26 connectors. The mating male connector is made by TE Connectivity (previously Tyco), part number 5749621-2, and can be purchased from Newark, Digikey, or similar vendors. The part number for the connector's backshell kit is 749608-2.

The SI, PZ5, PZ2, PZ3, IZ2, and IZ2H are all battery powered. To conserve power, each bank of channels will not turn on unless a headstage is connected. The device detects whether a headstage is connected through the HSD (HeadStage Detect) pins: pins 18 and 19. These pins should be shorted together on the headstage connector. If pins 18 and 19 are not shorted the headstage will not be detected and the bank that it is connected to will power off.

Important

This does not apply to the IZ2M and IZ2MH. In those devices all banks are always powered.

The pins on the headstage should be made to match the connector on the intended device. The pinouts for each device are shown below.

Note

The user must increment the channel numbers by 16 (or 8) according to the amp, mode and position of the connector. So, for the connector labeled 'A', A1 is channel 1 while on the connector labeled 'B', A1 may be channel 17.

PZA (SI) and PZ5 Analog Connector Pinout for Building Headstages

PZA (SI) and PZ5 Analog banks have 26-pin headstage connectors. The connectors are labeled alphabetically from bottom to top. Each connector carries signal for one bank of channels with ground and reference. The corresponding channel numbers depend on:

  1. the reference mode configurations

  2. the position of the bank in a logical amplifier.

For simplicity sake, the diagrams below assume channels for that connector begin with channel 1. For example, A1 - A16 represent the 16 channels coming from the connected headstage.

Local Mode

Pin Name Description Pin Name Description
1 A1 Analog Input Channels 14 V+ Positive Voltage (+2.5V)
2 A2 15 GND Ground
3 A3 16 GND
4 A4 17 V- Negative Voltage (-2.5V)
5 Ref Reference 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD
7 A5 Analog Input Channels 20 A6 Analog Input Channels
8 A7 21 A8
9 A9 22 A10
10 A11 23 A12
11 A13 24 A14
12 A15 25 A16
13 RefA Alternate Reference 26 DNC Do Not Connect

Local Mode Notes

  • Short pins 18 and 19 together.

  • Pins 14 and 17 can be used to power an active headstage. Each amp board on the PZ5 / PZA can source up to 100mA through the V+/V- power pins. If you have a higher current draw (over 100mA) then you will need an external battery pack to power your load.

None Mode

Pin Name Description Pin Name Description
1 A1 Analog Input Channels 14 V+ Positive Voltage (+2.5V)
2 A2 15 GND Ground
3 A3 16 GND
4 A4 17 V- Negative Voltage (-2.5V)
5 DNC Do Not Connect 18 HSD Headstage Detect
6 DNC 19 HSD
7 A5 Analog Input Channels 20 A6 Analog Input Channels
8 A7 21 A8
9 A9 22 A10
10 A11 23 A12
11 A13 24 A14
12 A15 25 A16
13 GND Ground 26 DNC Do Not Connect

None Mode Notes

  • Short pins 18 and 19 together.

  • Do NOT connect pin 5.

  • Pins 14 and 17 can be used to power an active headstage. Each amp board on the PZ5 / PZA can source up to 100mA through the V+/V- power pins. If you have a higher current draw (over 100mA) then you will need an external battery pack to power your load.

Shared Mode

Pin Name Description Pin Name Description
1 A1 Analog Input Channels 14 V+ Positive Voltage (+2.5V)
2 A2 15 GND Ground
3 A3 16 GND
4 A4 17 V- Negative Voltage (-2.5V)
5 Ref Reference 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD
7 A5 Analog Input Channels 20 A6 Analog Input Channels
8 A7 21 A8
9 A9 22 A10
10 A11 23 A12
11 A13 24 A14
12 A15 25 A16
13 GND Ground 26 DNC Do Not Connect

Shared Mode Notes

  • Short pins 18 and 19 together.

  • In Shared reference mode, only Pin 5 of the first bank of the logical amplifier is connected to the reference. It is shared internally among the other banks of the logical amplifier.

  • Pins 14 and 17 can be used to power an active headstage. Each amp board on the PZ5 / PZA can source up to 100mA through the V+/V- power pins. If you have a higher current draw (over 100mA) then you will need an external battery pack to power your load.

Differential Mode

Pin Name Description Pin Name Description
1 A1(+) Analog Input Channel 14 V+ Positive Voltage (+2.5V)
2 A1(-) Differential Analog Input Channel 15 GND Ground
3 A2(+) Analog Input Channel 16 GND Ground
4 A2(-) Differential Analog Input Channel 17 V- Negative Voltage (-2.5V)
5 NA Not Used 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD Headstage Detect
7 A3(+) Analog Input Channels 20 A3(-) Differential Input Channels
8 A4(+) 21 A4(-)
9 A5(+) 22 A5(-)
10 A6(+) 23 A6(-)
11 A7(+) 24 A7(-)
12 A8(+) 25 A8(-)
13 GND Ground 26 DNC Do Not Connect

Differential Mode Notes

  • There are 8 (+) channels and 8 (-) channels per DB26 connector. Subsequent banks are indexed by an additional 8 channels.

  • Short pins 18 and 19 together.

  • Pins 14 and 17 can be used to power an active headstage. Each amp board on the PZ5 / PZA can source up to 100mA through the V+/V- power pins. If you have a higher current draw (over 100mA) then you will need an external battery pack to power your load.

PZ2 Connector Pinout for Building Headstages

Pin Name Description Pin Name Description
1 A1 Analog Input Channels 14 V+ Positive Voltage (+1.5V)
2 A2 15 GND Ground
3 A3 16 DNC Do Not Connect
4 A4 17 V- Negative Voltage (-1.5V)
5 Ref Reference 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD
7 A5 Analog Input Channels 20 A6 Analog Input Channels
8 A7 21 A8
9 A9 22 A10
10 A11 23 A12
11 A13 24 A14
12 A15 25 A16
13 RefA Alternate Reference 26 DNC Do Not Connect

PZ2 Notes

  • Short pins 18 and 19 together.

  • Do NOT connect pins 6, 13, 16, or 26.

  • Pins 14 and 17 can be used to power an active headstage. Each amp board on the PZ5 / PZA can source up to 100mA through the V+/V- power pins. If you have a higher current draw (over 100mA) then you will need an external battery pack to power your load.

PZ3 Connector Pinout for Building Headstages

Pin Name Description Pin Name Description
1 A1(+) Analog Input Channel 14 V+ Positive Voltage (+1.5V)
2 A1(-) Differential Analog Input Channel 15 GND Ground
3 A2(+) Analog Input Channel 16 DNC Do Not Connect
4 A2(-) Differential Analog Input Channel 17 V- Negative Voltage (-1.5V)
5 Ref* Shared Reference 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD Headstage Detect
7 A3(+) Analog Input Channels 20 A3(-) Differential Input Channels
8 A4(+) 21 A4(-)
9 A5(+) 22 A5(-)
10 A6(+) 23 A6(-)
11 A7(+) 24 A7(-)
12 A8(+) 25 A8(-)
13 DNC Do Not Connect 26 DNC Do Not Connect

PZ3 Notes

  • * The PZ3 can operate in Shared or Individual (True Differential) mode.

    • If operating in Shared mode: do NOT connect differential analog input channels, pins 2, 4, 20-25.

    • If operating in Individual mode: do NOT connect pin 5.

  • There are 8 (+) channels and 8 (-) channels per DB26 connector. Subsequent banks are indexed by an additional 8 channels.

  • Short pins 18 and 19 together.

  • Do NOT connect pins 6, 13, 16, 26.

  • Pins 14 and 17 can be used to power an active headstage. Each amp board on the PZ5 / PZA can source up to 100mA through the V+/V- power pins. If you have a higher current draw (over 100mA) then you will need an external battery pack to power your load.

IZ2, IZ2M, IZ2MH, IZV Subject Interface (SI) Connector Pinout for Building Headstages

Pin Name Description Pin Name Description
1 A1 Analog Output Channels 14 DNC Do Not Connect
2 A2 15 GND Ground
3 A3 16 DNC Do Not Connect
4 A4 17 DNC Do Not Connect
5 DNC Do Not Connect 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD
7 A5 Analog Output Channels 20 A6 Analog Output Channels
8 A7 21 A8
9 A9 22 A10
10 A11 23 A12
11 A13 24 A14
12 A15 25 A16
13 DNC Do Not Connect 26 DNC Do Not Connect

IZ2 and IZV Notes

  • Short pins 18 and 19 together.

  • Do NOT connect pins 5, 6, 13, 14, 16, 17, or 26.

  • Only passive headstages can be used with the IZ2 and IZV.

IZ2H Connector Pinout for Building Headstages

Pin Name Description Pin Name Description
1 A1 Analog Output Channels 14 DNC Do Not Connect
2 A2 15 GND Ground
3 A3 16 DNC Do Not Connect
4 A4 17 DNC Do Not Connect
5 DNC Do Not Connect 18 HSD Headstage Detect
6 DNC Do Not Connect 19 HSD
7 A5 Analog Output Channels 20 A6 Analog Output Channels
8 A7 21 A8
9 DNC Do Not Connect 22 DNC Do Not Connect
10 DNC 23 DNC
11 DNC 24 DNC
12 DNC 25 DNC
13 DNC 26 DNC

IZ2H Notes

  • Short pins 18 and 19 together.

  • Do NOT connect pins 5, 6, 9-14, 16, 17, or 22-26.

  • Only passive headstages can be used with the IZ2H.

The ACO passes signals from each header to the pins on the associated DB26 connector on the face of the commutator. The unused pins should not be connected. The pins on the headstage should be made to map to the connected amplifier/stimulator via the header as follows:

ACO Headers - Pinout for Building Active Headstages

For PZ2, PZ5 Analog, or PZA Subject Interface (SI)

For PZ3

ACO Headers - Pinout for Building Passive Headstages

For IZ2, IZ2M, IZ2MH, or IZV Subject Interface (SI)

For IZ2H

PZ2/PZ3 Signal inversion

TN0868

Product: PZ2, PZ3
Version: PZ2-32:1006-1010, PZ2-64:2018-2025, PZ2-128:2020-2026, PZ2-256:2009-2010, PZ3 < 2000
Date Added: 2009-12-07

Issue

PZ2s and PZ3s with the above serial numbers will generate inverted signal outputs.

Workaround

Place an MCScale component with a SF of '-1' into your circuit to invert the data like the example shown below.

Solution

If you experience this issue contact TDT and request an RMA.

PZ3_ChanMap macro causes a warning in RPvdsEx

TN0848

Product: PZ3, RPvdsEx
Version: All
Date Added: 2009-04-09

Issue

When using the PZ3_ChanMap macro in RPvdsEx, the macro causes a warning message to be displayed even when used correctly. The warning message occurs when RPvdsEx detects a channel number mismatch between the RZ2_Input_MC macro and the PZ3_ChanMap macro.

Workaround

The RZ2_Input_MC macro is designed for the PZ2 preamplifier which contains 16 recording channels per bank. The PZ3 amplifier differs in that each bank contains 8 channels for recording and 8 channels for impedance testing. The number of channels parameter defined in the PZ3_ChanMap macro should be configured to output the number of recording channels according to the PZ3. This means that the RZ2_Input_MC macro will have double the number of channels compared to the PZ3_ChanMap macro.

For example, when using a 32-channel PZ3, the PZ3_ChanMap macro channel number parameter would be set to 32 while the RZ2_Input_MC macro channel number would need to be set to 64 (since the PZ3 has half the number of recording channels per bank compared to the PZ2). Refer to the images below for examples of how to correctly use the PZ3_ChanMap macro.

Correct

Incorrect

Ensure that the correct number of channels is set before attempting to use the circuit.