參數(shù)資料
型號: MAX1876AEEG
廠商: MAXIM INTEGRATED PRODUCTS INC
元件分類: 穩(wěn)壓器
英文描述: Fixed-Point Digital Signal Processor 288-BGA MICROSTAR
中文描述: DUAL SWITCHING CONTROLLER, 660 kHz SWITCHING FREQ-MAX, PDSO24
封裝: 0.150 INCH, 0.25 INCH PITCH, MO-137AE, QSOP-24
文件頁數(shù): 14/21頁
文件大?。?/td> 493K
代理商: MAX1876AEEG
M
An R
ILIM
resistance range of 100k
to 600k
corre-
sponds to a current-limit threshold of 50mV to 300mV.
When adjusting the current limit, 1% tolerance resistors
minimize error in the current-limit threshold.
For foldback current limit, a resistor (R
FBI
) is added
from ILIM pin to output. The value of R
ILIM
and R
FBI
can then be calculated as follows:
First select the percentage of foldback, P
FB
, from 15%
to 30%, then:
Input Capacitor
The input filter capacitor reduces peak currents drawn
from the power source and reduces noise and voltage
ripple on the input caused by the circuit
s switching.
The input capacitor must meet the ripple current
requirement (I
RMS
) imposed by the switching currents
as defined by the following equation:
I
RMS
has a maximum value when the input voltage
equals twice the output voltage (V
IN
= 2V
OUT
), so
I
RMS(MAX)
= I
LOAD
/ 2. For most applications, non-
tantalum capacitors (ceramic, aluminum, polymer, or
OS-CON) are preferred at the input due to their robust-
ness with high inrush currents typical of systems that
can be powered from very low impedance sources.
Additionally, two (or more) smaller-value low-ESR capac-
itors can be connected in parallel for lower cost. Choose
an input capacitor that exhibits less than +10
°
C temper-
ature rise at the RMS input current for optimal long-term
reliability.
Output Capacitor
The key selection parameters for the output capacitor
are capacitance value, ESR, and voltage rating. These
parameters affect the overall stability, output ripple volt-
age, and transient response. The output ripple has two
components: variations in the charge stored in the out-
put capacitor, and the voltage drop across the capaci-
tor
s ESR caused by the current flowing into and out of
the capacitor:
The output voltage ripple as a consequence of the ESR
and output capacitance is:
where I
P-P
is the peak-to-peak inductor current (see the
Inductor Selection
section). These equations are suit-
able for initial capacitor selection, but final values
should be verified by testing in a prototype or evaluation
circuit.
V
I
V
I
C
I
V
V
f
L
V
V
RIPPLE ESR
P P ESR
-
RIPPL( )
P P
OUT SW
P P
-
IN
OUT
SW
OUT
IN
(
)
=
=
=
-
-
8
V
V
V
RIPPLE
RIPPLE ESR
RIPPL( )
+
(
)
I
I
V
V
V
V
RMS
LOAD
OUT
IN
OUT
IN
=
(
)
-
R
P
V
(
P
and
R
V
P
V
R
P
-
V
FBI
FB
OUT
1
-
FB
ILIM
ITH
10
-
FB
ITH
FBI
FB
OUT
=
×
6
=
×
×
1
(
×
[
]
5 10
10
1
(
-
)
)
)
Dual 180° Out-of-Phase PWM Step-
Down Controllers with POR
14
______________________________________________________________________________________
MAX1875
OUT_
R_A
R_B
FB_
V
OUT_
> 1V
MAX1875
OUT_
R_C
R_A
FB_
REF
V
OUT_
< 1V
Figure 6. Adjustable Output Voltage
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MAX1876AEEG+ 功能描述:電壓模式 PWM 控制器 Dual 180 Out PWM Step-Down RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
MAX1876AEEG+T 功能描述:電壓模式 PWM 控制器 Dual 180 Out PWM Step-Down RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
MAX1876AEEG-T 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
MAX1876EEG 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
MAX1876EEG+ 功能描述:電壓模式 PWM 控制器 Dual 180 Out PWM Step-Down RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel