Excelsys CoolX1800, Designers Manual

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Section 7: CoolMod Signals
CoolMod Enable/Inhibit
Each CoolMod may be enabled/inhibited by means of a logic level signal applied to the enable
input on Output Signal Connector J1001-J1006, Pin 4 (Positive), Pin 1 or 3 (Negative). The
input has a 1K ohm series resistor and a 100nF filtering capacitor to filter noise on this signal.
The input voltage must be limited to no greater than 5 volts. There is a max 15mS Turn-On
Delay after application of the signal. When there is no connection, Pin 4 is HIGH (5V) and the
module is enabled. Pulling Pin 4 to Common will disable the module.
Disabling CmG-H modules in this way will disable both outputs.
CmG-H Enable/Inhibit
Each individual channel of the CmG or CmH may be enabled/inhibited by means of a signal
applied to the Inhibit pins on the Module Signal Connector J1. When the Inhibit pins are
floating, or when the +Inhibit pin is tied to the -Inhibit pin, the channel is enabled.
Applying a signal voltage to the Inhibit pins will disable the channel. The specifications of this
signal are shown in the table below.
Inhibit Signal Voltage Inhibit Signal Current
Maximum 12 V 4.0 mA
Minimum 3 V 0.2 mA
CoolMod Power Good Signal (CmA-F)
Each CoolMod has a Power Good signal that is the output of an internal comparator which
monitors the output voltage and determines whether this voltage is within normal operation
limits. The Power Good signal is an unbiased open collector that is available on the Output
Signal Connector (J1001-J1006) via the collector on Pin 2 and the emitter on Pin 1 or 3
(Common).
There is a 390Ω resistor in series with the collector for current limiting .
When the output voltage is within 10% of Vset the transistor is turned ON. If the output drops
out of regulation the transistor turns OFF. This can be used for power sequencing in many
applications (enabling another CoolMod output when the first output is within regulation, as
well as driving external circuitry.