FEATURES DESCRIPTIONS (CON.)
For example, to program the output voltage of the DNL
module to 3.3Vdc, Rtrim is calculated as follows:
Over-Temperature Protection
10500
The over-temperature protection consists of circuitry
that provides protection from thermal damage. If the
temperature exceeds the over-temperature threshold
the module will shut down. The module will try to restart
after shutdown. If the over-temperature condition still
exists during restart, the module will shut down again.
This restart trial will continue until the temperature is
within specification
Rtrim :=
− 1000 ⋅Ω
2.5475
Rtrim = 3.122 kΩ
DNL can also be programmed by applying a voltage
between the TRIM and GND pins (Figure 36). The
following equation can be used to determine the value of
Vtrim needed for a desired output voltage Vo:
Remote Sense
(
)
Vtrim := 0.7 − Vo − 0.7525 ⋅0.0667
The DNL provide Vo remote sensing to achieve proper
regulation at the load points and reduce effects of
distribution losses on output line. In the event of an
open remote sense line, the module shall maintain local
sense regulation through an internal resistor. The
module shall correct for a total of 0.1V of loss. The
remote sense line impedance shall be < 10Ω.
Vtrim is the external voltage in V
Vo is the desired output voltage
For example, to program the output voltage of a DNL
module to 3.3 Vdc, Vtrim is calculated as follows
Distribution Losses
Distribution Losses
Vin
Vo
(
)
Vtrim := 0.7 − 2.5475⋅0.0667
Vtrim = 0.530V
Sense
RL
GND
Distribution Losses
Distribution Losses
Figure 31: Effective circuit configuration for remote sense
operation
Output Voltage Programming
Figure 32: Circuit configuration for programming output voltage
using an external resistor
The output voltage of the DNL can be programmed to
any voltage between 0.75Vdc and 5.0Vdc by
connecting one resistor (shown as Rtrim in Figure 35)
between the TRIM and GND pins of the module.
Without this external resistor, the output voltage of the
module is 0.7525 Vdc. To calculate the value of the
resistor Rtrim for a particular output voltage Vo, please
use the following equation:
10500
Rtrim :=
− 1000 ⋅Ω
Vo − 0.7525
Figure 33: Circuit Configuration for programming output voltage
using external voltage source
Rtrim is the external resistor in Ω
Vo is the desired output voltage
DS_DNL10SMD_07182012
9
DELTA [ DELTA ELECTRONICS, INC. ]
