The model 3158/3159 is a single width module containing a data register that can be written and read, a 12 bit digital-to-analog converter to provide an analog output, four digital control signals, and provisions for reading eight bits of status information. Data sent to the module is in 2's complement form. It is left justified in a 16 bit word. The sign bit (W16) controls the polarity relay. There are two strap selectable modes for the output voltage. The module number depends on the mode chosen. In the bi-polar mode (3158), the analog output voltage is proportional to the number in the data register. The least significant bit of data is written from W5 in this mode. In the uni-polar output mode (3159), the output voltage is proportions to the absolute magnitude of the 2's complement number in the data register. In this case, the least significant bit is written from W4.
The analog output is a 0 to +10 volt signal supplied from a precision operational amplifier. Its low-impedence, single-ended output is intended to drive a differential input amplifier located at the power supply. Short and long term drift are less than 1/2 LSB. Strapping options are provide for +-10 volt +-5 volt and +-2.5 volt output. The output is set to zero when the crate power is turned on.
The four digital control signals are TURN ON, TURN OFF, RESET, and POLARITY. Each output is floating relay contact rated at 28 volts, .1 amp. Arc suppression protection circuits for the contacts are provided. TURN ON and RESET signals are momentary relay closures, 200 milliseconds in duration, which are triggered by CAMAC commands. TURN OFF, also triggered by command, is a momentary 2300 millisecond opening of the relay contact. POLARITY is a DC signal wherein the state of the relay is governed by data bit 16.
The mom momentary TURN ON and TURN OFF signals are intended for use in pushbutton on-off circuits. An external latching relay is required to latch the supply ON. Since the TURN OFF signal is normally closed, the interconnections circuit is fail-safe in that the supply will turn off if the interface circuit becomes disconnected. A circuit is provided to inhibit the TURN ON signal during power up.
An eight-bit input gate is provided for the reading of low-true status information from the power supply. A TRUE input is represented by an impedance to ground of less than 100 ohms. Ground-connected relay contacts, TTL outputs and common-emitter transistor circuits are satisfactory sources of data.
DATA ENABLE and DATA DISABLE inputs allow the analog control output signal to be switched ON and OFF by external, positive true pulses. This feature allows pulsing of power supplies, where practical, to conserve power. The pulse inputs can be disabled by dataway command. On power up the data is enabled and the pulse inputs disabled.
A jack-screw is provided which functions both in insertions and in extraction of the module. There is an N light that flashes whenever this module is addressed. Test points are provided for monitoring the output voltage. Two LEMO connectors are provided for the ON and OFF pulses.
|F(0)A(0)||Gates data register onto dataway|
|F(1)A(0)||Gates status bits, including DATA ENABLE and PULSE ENABLE, onto dataway|
|F(6)A(0)||Gates module number (3158 or 3159) onto dataway|
|F(9)A(0)||Clears data register, enabled data, and disabled pulse inputs|
|F(12)A(0)||triggers RESET function|
|F(16)A(0)||Writes data register|
|F(24)A(0)||Disables pulse inputs|
|F(26)A(0)||Enables pulse inputs|
|F(28)A(0)||Triggers TURN OFF function|
|F(30)A(0)||Triggers TURN ON function|
|Z*S2||Clears data register, enables data, and disables pulse inputs|
|2L|| ||2R|| |
|4L|| ||4R|| |
|5L|| ||5R|| |
|8L|| ||8R|| |
|9L|| ||9R|| |
|10L||Status 7||10R|| |
|11L||Status 5||11R|| |
|12L||Status 8||12R|| |
|13L||Status 6||13R|| |
|14L||Status 3||14R|| |
|15L||Status 4||15R|| |
|16L||Status 2||16R||Status 1|
|17L|| ||17R||Analog Out +|
|18L|| ||18R||Analog Out -|