- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄363234 > NCV4279BDW (ON SEMICONDUCTOR) 5.0 V Micropower 150 mA LDO Linear Regulator with DELAY, Adjustable RESET, and Monitor FLAG PDF資料下載
參數(shù)資料
| 型號： | NCV4279BDW |
| 廠商： | ON SEMICONDUCTOR |
| 元件分類： | 基準(zhǔn)電壓源/電流源 |
| 英文描述： | 5.0 V Micropower 150 mA LDO Linear Regulator with DELAY, Adjustable RESET, and Monitor FLAG |
| 中文描述： | 5 V FIXED POSITIVE LDO REGULATOR, 0.6 V DROPOUT, PDSO20 |
| 封裝： | SO-20 |
| 文件頁數(shù)： | 8/12頁 |
| 文件大?。?/td> | 102K |
| 代理商： | NCV4279BDW |
NCV4279B
http://onsemi.com
8
APPLICATION NOTES
FLAG MONITOR
Figure 14 shows the FLAG Monitor waveforms as a result
of the circuit depicted in Figure 13. As the output voltage
falls (V
OUT
), the Monitor threshold is crossed. This causes
the voltage on the FLAG output to go low sending a warning
signal to the microprocessor that a RESET signal may occur
in a short period of time. T
WARNING
is the time the
microprocessor has to complete the function it is currently
working on and get ready for the RESET shutdown signal.
Figure 14. FLAG Monitor Circuit Waveform
V
OUT
MON
RESET
FLAG Monitor
Ref. Voltage
T
WARNING
FLAG
SETTING THE DELAY TIME
The delay time is controlled by the Reset Delay Low
Voltage, Delay Switching Threshold, and the Delay Charge
Current. The delay follows the equation:
[CDELAY(Vdt
Delay Charge Current
Example:
Using C
DELAY
= 33 nF.
Assume reset Delay Low Voltage = 0.
Use the typical value for V
dt
= 1.8 V.
Use the typical value for Delay Charge Current = 2.5 A.
[33 nF(1.8
2.5 A
tDELAY
Reset Delay Low Voltage)]
tDELAY
0)]
23.8 ms
STABILITY CONSIDERATIONS
The output or compensation capacitor helps determine
three main characteristics of a linear regulator: startup
delay, load transient response and loop stability.
The capacitor value and type should be based on cost,
availability, size and temperature constraints. A tantalum or
aluminum electrolytic capacitor is best, since a film or
ceramic capacitor with almost zero ESR can cause
instability. The aluminum electrolytic capacitor is the least
expensive solution, but, if the circuit operates at low
temperatures (25
°
C to 40
°
C), both the value and ESR of
the capacitor will vary considerably. The capacitor
manufacturers data sheet usually provides this information.
The value for the output capacitor C
OUT
shown in Figure 15
should work for most applications, however it is not
necessarily the optimized solution.
Figure 15. Test and Application Circuit Showing
Output Compensation
V
IN
V
OUT
C
OUT
**
10 F
R
RST
RESET
C
IN
*
0.1 F
NCV4279B
*C
IN
required if regulator is located far from the power supply filter.
**C
OUT
required for stability. Capacitor must operate at minimum
temperature expected.
CALCULATING POWER DISSIPATION IN A
SINGLE OUTPUT LINEAR REGULATOR
The maximum power dissipation for a single output
regulator (Figure 16) is:
PD(max)
[VIN(max)
VIN(max)IQ
VOUT(min)]IOUT(max)
(1)
where:
V
IN(max)
is the maximum input voltage,
V
OUT(min)
is the minimum output voltage,
I
OUT(max)
is the maximum output current for the
application, and
I
Q
is the quiescent current the regulator consumes at
I
OUT(max)
.
Once the value of P
D(max)
is known, the maximum
permissible value of R
JA
can be calculated:
150
°
C
RJA
TA
PD
(2)
The value of R
JA
can then be compared with those in the
package section of the data sheet. Those packages with
R
JA
’s less than the calculated value in equation 2 will keep
the die temperature below 150
°
C.
In some cases, none of the packages will be sufficient to
dissipate the heat generated by the IC, and an external
heatsink will be required.
SMART
REGULATOR
I
Q
Control
Features
I
OUT
I
IN
Figure 16. Single Output Regulator with Key
Performance Parameters Labeled
V
IN
V
OUT
}
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| NCV4279BDWR2 | 5.0 V Micropower 150 mA LDO Linear Regulator with DELAY, Adjustable RESET, and Monitor FLAG |
| NCV4279BD1 | 5.0 V Micropower 150 mA LDO Linear Regulator with DELAY, Adjustable RESET, and Monitor FLAG |
| NCV4279BD1R2 | 5.0 V Micropower 150 mA LDO Linear Regulator with DELAY, Adjustable RESET, and Monitor FLAG |
| NCV4279BD2 | 5.0 V Micropower 150 mA LDO Linear Regulator with DELAY, Adjustable RESET, and Monitor FLAG |
| NCV4299 | 5.0V Low Drop Fixed Voltage Regulator(5.0V，低壓差固定電壓穩(wěn)壓器) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| NCV4279BDWG | 功能描述:低壓差穩(wěn)壓器 - LDO ANA 5.0V MICROPOWER RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| NCV4279BDWR2 | 功能描述:低壓差穩(wěn)壓器 - LDO ANA 5.0V MICROPOWER RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| NCV4279BDWR2G | 功能描述:低壓差穩(wěn)壓器 - LDO ANA 5.0V MICROPOWER RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| NCV4279CD2R2G | 制造商:ON Semiconductor 功能描述:150MA LDO LINEAR REGULATOR, PB FREE - Tape and Reel |
| NCV4279D1 | 功能描述:低壓差穩(wěn)壓器 - LDO 5V 150mA MicroPower RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。