CM4 App Note 260424 issue 2.1.docx
Document No. 260424
Page 16 of 29
9. Advanced Output Module Features
Remote Voltage Programming (External Voltage Control)
The output voltage of the module can be adjusted using an external voltage source connected between the COM and V
CONTROL
pins on the
signals connector J4 as shown below.
In this configuration the output voltage will follow the typical equation below,
V
O
= V
SET
((5-V
CONTROL
) / 3.8), where V
SET
is the manual preset voltage of the module.
Equivalent internal circuit
Control function
The output voltage can be controlled from 0% to 131.5% of the preset voltage using this control method. However, care must be taken to ensure
the output voltage does not exceeed the OVP level, as this will trigger OVP protection.
Remote adjustment of the output voltage using the V
CONTROL
pin does not affect the preset power good threshold. Hence, remotely adjusting the
output voltage below 0.9*Vset will cause the power good signal to go low.
Where tight voltage adjustment tolerances are required, it is recommended to use external circuitry to provide closed loop control of the V
CONTROL
pin.
