OVERVIEW
The Model 7120 is a calibrated programmable Charge Source/Time Interval generator packaged in a double width CAMAC module. It was specifically designed for testing and calibrating charge-to-digital and time-to-digital converter circuits.
The various full scale ranges and operating modes of the Model 7120 are selected by front panel switches which provide full manual control of all operating modes. The positions of these switches can be read out via CAMAC. Control of CHARGE and TIME outputs is either MANUAL via front panel 15-turn potentiometers or CAMAC via internal Digital to Analog Converters (DACs).
The 7120 contains a Primary DAC (16 bits) and a Secondary DAC (8 bits) for precise CAMAC control of its outputs. A two-position toggle switch (PRIMARY OUT) is used to select whether the CHARGE output or the TIME outputs (GATE, START, STOP) will be connected to the Primary DAC. The non-primary section (TIME or CHARGE) gets connected to the SECONDARY DAC. When testing a gated current integrating ADC, the PRIMARY DAC output would normally be CHARGE, so as to provide finer control over the CHARGE OUT signal as compared to the GATE signal. The TIME outputs would be selected as Primary when testing TDCs, or whenever finer control over the time interval is desired. The ± DC outputs always track the section designated as the Primary DAC, regardless of the position of its CAMAC/MANUAL switch.