- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄383512 > MAX861ISA (MAXIM INTEGRATED PRODUCTS INC) Quadruple 2-Input Positive-NOR Gates 14-CFP -55 to 125 PDF資料下載
參數(shù)資料
| 型號： | MAX861ISA |
| 廠商： | MAXIM INTEGRATED PRODUCTS INC |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | Quadruple 2-Input Positive-NOR Gates 14-CFP -55 to 125 |
| 中文描述： | SWITCHED CAPACITOR CONVERTER, 250 kHz SWITCHING FREQ-MAX, PDSO8 |
| 封裝： | 0.150 INCH, PLASTIC, SOIC-8 |
| 文件頁數(shù)： | 8/12頁 |
| 文件大?。?/td> | 142K |
| 代理商： | MAX861ISA |
M
50mA, Frequenc y-S elec table,
S witc hed-Capac itor Voltage Converters
8
_______________________________________________________________________________________
MAX860
MAX861
“n”
MAX860
MAX861
“1”
8
7
5
V
OUT
C2
8
7
+V
IN
C1
C1
2
2
3
3
4
4
5
V
OUT
= -V
IN
OUT
= R
OUT
OF SINGLE DEVICE
R
…
…
Figure 2. Paralleling MAX860s or MAX861s to Reduce Output
Resistance
MAX860
MAX861
“n”
MAX860
MAX861
“1”
8
7
5
V
OUT
C2
8
7
+V
IN
C1
C2
C1
2
2
3
3
4
4
5
V
OUT
= -nV
IN
…
…
Figure 1. Cascading MAX860s or MAX861s to Increase
Output Voltage
Flying Capacitor, C1
Increasing the size of the flying capacitor reduces the
output resistance.
Output Capacitor, C2
Increasing the size of the output capacitor reduces the
output ripple voltage. Decreasing its ESR reduces both
output resistance and ripple. Smaller capacitance val-
ues can be used if one of the higher switching frequen-
cies is selected, if less than the maximum rated output
current (50mA) is required, or if higher ripple can be
tolerated. The following equation for peak-to-peak rip-
ple applies to both the inverter and doubler circuits.
I
OUT
V
RIPPLE
= ———————— + 2 x I
OUT
x ESR
C2
2 x f
S
x C2
Bypass Capacitor
Bypass the incoming supply to reduce its AC impedance
and the impact of the MAX860/MAX861’s switching
noise. The recommended bypassing depends on the cir-
cuit configuration and where the load is connected.
When the inverter is loaded from OUT to GND or the
doubler is loaded from V
DD
to GND, current from the
supply switches between 2 x I
OUT
and zero. Therefore,
use a large bypass capacitor (e.g., equal to the value
of C1) if the supply has a high AC impedance.
When the inverter and doubler are loaded from V
DD
to
OUT, the circuit draws 2 x I
OUT
constantly, except for
short switching spikes. A 0.1μF bypass capacitor is
sufficient.
Casc ading Devic es
Two devices can be cascaded to produce an even
larger negative voltage, as shown in Figure 1. The
unloaded output voltage is nominally -2 x V
IN
, but this is
reduced slightly by the output resistance of the first
device multiplied by the quiescent current of the sec-
ond. The output resistance of the complete circuit is
approximately five times the output resistance of a sin-
gle MAX860/MAX861.
Three or more devices can be cascaded in this way,
but output resistance rises dramatically, and a better
solution is offered by inductive switching regulators
(such as the MAX755, MAX759, MAX764, or MAX774).
Connect LV as with a standard inverter circuit (see Pin
Description.
Paralleling Devic es
Paralleling multiple MAX860s or MAX861s reduces the
output resistance. As illustrated in Figure 2, each
device requires its own pump capacitor (C1), but the
reservoir capacitor (C2) serves all devices. C2’s value
should be increased by a factor of n, where n is the
number of devices. Figure 2 shows the equation for cal-
culating output resistance. An alternative solution is to
use the MAX660 or MAX665, which are capable of sup-
plying up to 100mA of load current. Connect LV as with
a standard inverter circuit (see Pin Description.
Combined Doubler/Inverter
In the circuit of Figure 3, capacitors C1 and C2 form the
inverter, while C3 and C4 form the doubler. C1 and C3
are the pump capacitors; C2 and C4 are the reservoir
capacitors. Because both the inverter and doubler use
part of the charge-pump circuit, loading either output
causes both outputs to decline towards GND. Make
sure the sum of the currents drawn from the two out-
puts does not exceed 60mA. Connect LV as with a
standard inverter circuit (see Pin Description.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MAX861MJA | 50mA, Frequency-Selectable, Switched-Capacitor Voltage Converters |
| MAX872-MAX874 | 10レA, Low-Dropout, Precision Voltage References |
| MAX872CPA | 8-Bit Identity/Magnitude Comparators (P=Q) with Enable 20-CFP -55 to 125 |
| MAX872CSA | 8-Bit Identity/Magnitude Comparators (P=Q) with Enable 20-CDIP -55 to 125 |
| MAX872EPA | 8-Bit Identity/Magnitude Comparators (P=Q) with Enable 20-LCCC -55 to 125 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MAX861ISA+ | 功能描述:電荷泵 50mA f-Selectable Switched-Cap V Conv RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 輸出電壓:- 1.5 V to - 5.5 V, 3 V to 11 V 輸出電流:100 mA 電源電流:1 mA 最大工作溫度:+ 70 C 封裝 / 箱體:SOIC-8 Narrow 封裝:Tube |
| MAX861ISA+T | 功能描述:電荷泵 50mA f-Selectable Switched-Cap V Conv RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 輸出電壓:- 1.5 V to - 5.5 V, 3 V to 11 V 輸出電流:100 mA 電源電流:1 mA 最大工作溫度:+ 70 C 封裝 / 箱體:SOIC-8 Narrow 封裝:Tube |
| MAX861ISA-T | 功能描述:電荷泵 50mA f-Selectable Switched-Cap V Conv RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 輸出電壓:- 1.5 V to - 5.5 V, 3 V to 11 V 輸出電流:100 mA 電源電流:1 mA 最大工作溫度:+ 70 C 封裝 / 箱體:SOIC-8 Narrow 封裝:Tube |
| MAX861ISA-TG069 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX861IUA | 功能描述:電荷泵 50mA f-Selectable Switched-Cap V Conv RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 輸出電壓:- 1.5 V to - 5.5 V, 3 V to 11 V 輸出電流:100 mA 電源電流:1 mA 最大工作溫度:+ 70 C 封裝 / 箱體:SOIC-8 Narrow 封裝:Tube |
發(fā)布緊急采購，3分鐘左右您將得到回復。