KEPCO BHK-MG 40W (Half Rack) Series - Manual (Page 79)

BHK-1/2-MG 121313
3-35
FIGURE 3-9. ANALOG PROGRAMMING OF OUTPUT VOLTAGE (VOLTAGE MODE)
OR VOLTAGE LIMIT (CURRENT MODE) USING RESISTANCE
For either voltage programming or current programming, the external resistor R
EXT
connected
across terminals 6 and 8 of VOLTAGE PROG terminal strip TB2 or CURRENT PROG. terminal
strip TB3 functions as a feedback resistor for the internal uncommitted amplifier dedicated to
voltage or current programming. This uncommitted amplifier is configured to amplify and invert
the +10V reference applied via terminals 4 and 6 of TB2 or TB3. The output of the uncommitted
amplifier is applied via terminals 8 and 9 of TB2 or TB3 to a summing network at the input of the
summing amplifier. For voltage programming, the other input to the summing amplifier, DP (V),
is from the voltage portion of the digital programming circuitry (either from the keypad or the
GPIB bus). For current programming, the other input to the summing amplifier, DP (C), is from
the current portion of the digital programming circuitry (either from the keypad or the GPIB bus).
TABLE 3-10. FEEDBACK RESISTOR AND CURRENT SENSING RESISTOR VALUES
RESISTOR BHK 300-130MG BHK 500-80MG BHK 1000-40MG BHK 2000-0.02MB
Voltage Feedback Resistor R
(Ohms)
300K* 500K* 1000K* 2000K*
Current Sensing Resistor Rs
(Ohms)
0.008K* 0.0125K* 0.025K* 0.050K*
* All resistors are 1% tolerance.