- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄300051 > UNR-3.3/10-D12SM 1-OUTPUT 33 W DC-DC REG PWR SUPPLY MODULE PDF資料下載
參數(shù)資料
| 型號(hào)： | UNR-3.3/10-D12SM |
| 元件分類： | 電源模塊 |
| 英文描述： | 1-OUTPUT 33 W DC-DC REG PWR SUPPLY MODULE |
| 文件頁(yè)數(shù)： | 6/10頁(yè) |
| 文件大?。?/td> | 239K |
| 代理商： | UNR-3.3/10-D12SM |
UNR Models
N O N - I S O L A T E D , 1 8 - 3 3 W , 5 & 1 2 V - I N P U T D C / D C C O N V E R T E R S
Output Voltage Trimming
UNR 18-33W devices can be trimmed to any voltage between 1.50V and
3.55V. Trimming is accomplished with either a trimpot or a single xed resis-
tor. The trimpot should be connected between +Output and Output Return
with its wiper connected to the Trim pin as shown in Figure 3 below.
A trimpot can be used to determine the value of a single xed resistor
which should be connected, as shown in Figure 4, between the Trim pin and
+Output to trim down the output voltage, or between the Trim pin and Output
Return to trim up the output voltage. Fixed resistors should be metal-lm
types with absolute TCR’s less than 100ppm/
°C to ensure stability.
The equations below can be used as starting points for selecting specic
trim-resistor values. Recall that untrimmed devices are guaranteed to be
between
±1% and ±2% accurate, depending on model. See Performance
and Functional Specications.
5
LOAD
20k
5-10
Turns
+INPUT
INPUT
RETURN
+OUTPUT
TRIM
OUTPUT
RETURN
Trim
Down
Trim Up
LOAD
+INPUT
INPUT
RETURN
+OUTPUT
TRIM
OUTPUT
RETURN
Figure 4.Trim Connections Using Fixed Resistors
Note: Install either a xed trim-up resistor or a xed trim-down resistor
depending upon desired output voltage.
When the output current of a thermally stabilized converter exceeds the
maximum rating by 40% (typical) to 80% (maximum), the internal overcurrent
detection circuit shuts down the converter by discharging the soft-start circuit
of the pulse width modulator (PWM). In this off state, which is similar to that
achieved by pulling the On/Off Control low, the output voltage quickly drops
as the output capacitors discharge into the load. Since there is no longer any
output current, the overcurrent detection circuit is released, allowing the soft-
start circuit to recharge and the converter to turn on again. If the faulty load
condition persists, the overcurrent detection circuit will again discharge the
soft-start circuit and shut down the converter. This continuous on/off cycling
of the converter is referred to as “hiccup mode.” Once the overload condition
is removed, the converter remains on, and the output voltage is quickly
restored to its regulated value.
The components used to sense the output current have large temperature
coefcients. Consequently, in a "cold-start" situation, the Overcurrent Detec-
tion Point may temporarily move to 80% to 120% above the rated current
specication. The device quickly heats up, particularly if an overload situation
exists, and restores the normal (40%) Overcurrent Detection Point. The
device will not be damaged by starting up into an output-short-circuit condition.
The overcurrent detection circuitry helps keep internal current levels and
operating temperatures within safe operating limits. Nevertheless, sustained
operation at current levels above the rated output current but below the Over-
current Detection Point may result in permanent damage to the converter.
Figure 3.Trim Connections Using a Trimpot
UNR-1.8/10-D5T
UNR-1.8/10-D5SM
UNR-2.5/10-D5T
UNR-2.5/10-D5SM
–1.74
UP
RT (k
) =
VO – 1.8
3.14
–1.74
DOWN
RT
(k
) =
2.5 – VO
7.5(VO – 1.26)
–1.74
UP
RT (k
) =
VO – 2.5
9.47
–1.0
DOWN
RT
(k
) =
3.3 – VO
7.5(VO – 1.27)
UNR-3.3/8-D5T
UNR-3.3/8-D5SM
UNR-3.3/10-D5T
UNR-3.3/10-D5SM
UNR-3.3/8-D12T
UNR-3.3/8-D12SM
UNR-3.3/10-D12T
UNR-3.3/10-D12SM
–1.0
UP
RT (k
) =
VO – 3.3
9.5
–1.0
DOWN
RT
(k
) =
3.3 – VO
7.5(VO – 1.26)
–1.0
UP
RT (k
) =
VO – 3.3
9.41
–1.74
DOWN
RT
(k
) =
1.8 – VO
2.49(VO – 1.26)
Note: Resistor values are in k
. Accuracy of adjustment is subject to
tolerances of resistors and factory-adjusted output accuracy.
VO = desired output voltage.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| UNR5112(UN5112) | Composite Device - Transistors with built-in Resistor |
| UNR5113(UN5113) | Composite Device - Transistors with built-in Resistor |
| UNR5114(UN5114) | Composite Device - Transistors with built-in Resistor |
| UNR5115(UN5115) | Composite Device - Transistors with built-in Resistor |
| UNR511M(UN511M) | 複合デバイス － 抵抗內(nèi)蔵型トランジスタ |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| UNR4110 | 制造商:PANASONIC 制造商全稱:Panasonic Semiconductor 功能描述:Silicon PNP epitaxial planar type |
| UNR4110(UN4110) | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Composite Device - Transistors with built-in Resistor |
| UNR4110Q | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:TRANSISTOR | 50V V(BR)CEO | 100MA I(C) | SPAK |
| UNR4110R | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:TRANSISTOR | 50V V(BR)CEO | 100MA I(C) | SPAK |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。