FEATURES DESCRIPTIONS (CON.)
Over-Temperature Protection
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
For example, to program the output voltage of the DNL
module to 3.3Vdc, Rtrim is calculated as follows:
Rtrim
:=
⎜
⎛
10500
−
1000
⎞
⋅ Ω
⎟
⎝
2.5475
⎠
Rtrim = 3.122 kΩ
DNL can also be programmed by applying a voltage
between the TRIM and GND pins (Figure 35). The
following equation can be used to determine the value of
Vtrim needed for a desired output voltage Vo:
Vtrim
:=
0.7
−
⎡
(
Vo
−
0.7525
)
⋅
0.0667
⎤
⎣
⎦
Remote Sense
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.
Distribution Losses
Vin
Vo
Distribution Losses
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
Vtrim
:=
0.7
−
(
2.5475
⋅
0.0667
)
Sense
RL
Vtrim = 0.530V
GND
Distribution Losses
Distribution Losses
Figure 33:
Effective circuit configuration for remote sense
operation
Output Voltage Programming
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 34) 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:
Rtrim
:=
⎜
Figure 34:
Circuit configuration for programming output voltage
using an external resistor
⎛
10500
−
1000
⎞
⋅ Ω
⎟
⎝
Vo
−
0.7525
⎠
Figure 35:
Circuit Configuration for programming output voltage
using external voltage source
Rtrim is the external resistor in
Ω
Vo is the desired output voltage
PRELIMINARY DS_DNL10SIP20_10132008
10
DELTA [ DELTA ELECTRONICS, INC. ]
