GE VMIVME-3100 16 channel 12 bit analog-to-digital converter board

GE VMIVME-3100 16 channel 12 bit analog-to-digital converter board

Product Overview

VMIVME-3100 is a mid performance 12 bit analog-to-digital converter (ADC) board that supports 16 single ended or 8-channel differential front-end analog inputs, as well as multiple multiplexing expansion boards. Expansion board utilizing AMXbus ™ The analog signal is routed from the multiplexer input to the ADC board, which also has built-in testing capabilities. The fault LED on the front-end panel can provide users with fault detection and isolation capabilities.

Core functions and parameters

Key Features

12 bit resolution, maximum conversion time of 9 μ s, acquisition time of 9 μ s (can be selected based on full-scale input voltage).

16 channel single ended multiplexer, 8-channel differential input option.

Onboard built-in testing logic for fault detection and isolation, equipped with front-end panel fault LED.

Onboard precision voltage source, supporting self check.

You can choose one ADC per slot or one ADC plus a slave MUX board.

It has overvoltage protection input, separate encoding/key controlled VME connector, dual European card appearance, and fault safety function in case of power failure.

Throughput

Analog to digital (A/D) throughput: The throughput time of the operation is the sum of the amplifier setup time (acquisition time) and the A/D conversion time. The A/D conversion time is 9 μ s, and the amplifier setup time depends on the input voltage range and gain setting.

System throughput: Supports multiple multiplexing expansion boards, and the total system throughput can be calculated according to the relevant formula, which is

F S= N(T 1+T 2+T 3)1（ Samples per second）， Where N is the number of channels, T1 is the acquisition time of the remote multiplexer, T2 is the setup time of the VMIVME-3100 amplifier, and T3 is the conversion time of the VMIVME-3100 ADC.

protection function

16 front-end analog inputs have overvoltage protection. When the+15V power supply is turned on, the maximum input voltage range is ± 35V; when the power supply is turned off, the maximum input voltage is+20V.

Operation Mode

Normal mode operation

Analog signals can be transmitted through the front panel P3 connector or AMXbus ™ (P2 connector) receiving, AMXbus ™ Supports multiple analog input multiplexing expansion boards.

The front-end panel input (P3 connector) supports 8 differential or 16 single ended analog inputs. In single ended mode, each input has a related ground signal, and multiple low-pass filter options are also available.

AMXbus ™ The operation supports connecting up to 16 VMIC multiplexer boards to one ADC, achieving high-density and low-cost analog input expansion, and also supports built-in testing functions related to VMIC analog output boards.

ADC conversion can be initiated through an external TTL compatible signal, and the external trigger conversion circuit is enabled by setting the bit in the control word.

Built in testing mode

The ADC board contains a Control Status Register (CSR), which can be used to select certain operating modes. Users can use the read and write capabilities of CSR to verify the DO-D14 function of VMIVME-3100 VMEbus logic.

On board 9 precision voltage sources (-10.000V, -7.500V, -5.000V, -2.500V, 0.000V,+2.500V,+5.000V,+7.500V,+10.000V) can be selected by the user testing subroutine to verify the correct operation and accuracy of the board, and can also be used for calibration.

Can be accessed through AMXbus ™ Interconnect VMIVME-3100, VMIVME-41XX, and VMIVME-32XX boards to perform loop testing from analog output to analog input. It can also be used in conjunction with VMIVME-4500 for fault detection and isolation.

VMEbus interface description

The VMEbus interface of VMIVME-3100 includes the logic required to connect the slave board to VMEbus and perform memory mapping in the VMEbus short I/O address space. In the write cycle of the board address, bits A01 to A15 are compared with the previously selected board address, which is selected by the DIP switch. If the address matches, a board selection signal is generated, which, together with the control signal received on the board, gates the data (DO to D15) to the CSR on VMIVME-3100.

The circuit requires+5V,+15V, and -15V voltages, with+5V provided to the board through P1 and P2 connectors. The onboard DC-DC converter generates+15V and -15V for the analog circuit.

Programming related

Overview

The ADC board performs memory mapping in the VME short I/O address space, occupying only one word position within the 65535 byte VME short I/O address space. The board address is selected by DIP switches, and the short I/O space is mapped from FF0000 (hexadecimal) to FFFFF (hexadecimal). The ADC data register containing 12 bit converted digital data is a read-only register, while the control status register (CSR) is a read-write register used for board control. Since these two registers use the same address, CSR access and ADC conversion end register access are selected through data bit D15.

Description of Control Status Register (CSR)

The operating mode of the CSR programming selection board, CSR is a 16 bit read-write register. To initiate AD conversion, it is necessary to set data bit D6 in CSR and program data bits DO to D5 and D8 to D14 according to the desired operating mode. Data bit D15 is used to distinguish between two possible read cycles. Writing "0" to CSR can read the converted digital data from the ADC data register, while writing "1" can read CSR.