參數(shù)資料
型號(hào)： MAX1540A
廠商： Maxim Integrated Products, Inc.
英文描述： Dual Step-Down Controllers with Saturation Protection, Dynamic Output, and Linear Regulator
中文描述： 雙路、降壓型控制器，帶有電感飽和保護(hù)、動(dòng)態(tài)輸出和線性穩(wěn)壓器
文件頁(yè)數(shù)： 41/49頁(yè)
文件大小： 794K
代理商： MAX1540A
A reasonable minimum value for h is 1.5, but adjusting
this up or down allows trade-offs between V
SAG
, output
capacitance, and minimum operating voltage. For a
given value of h, the minimum operating voltage can be
calculated as:
where V
DROP1
is the parasitic voltage drop in the
charge path (see the
On-Time One-Shot (TON)
section),
t
OFF(MIN)
is from the
Electrical Characteristics
, and K is
taken from Table 3. The absolute minimum input voltage
is calculated with h = 1.
If the calculated V
IN(MIN)
is greater than the required
minimum input voltage, then operating frequency must
be reduced or output capacitance added to obtain an
acceptable V
SAG
. If operation near dropout is anticipat-
ed, calculate V
SAG
to be sure of adequate transient
response.
Dropout Design Example
V
OUT2
= 2.5V
f
SW
= 355kHz
K = 3.0μs, worst-case K
MIN
= 3.3μs
t
OFF(MIN)
= 500ns
V
DROP1
= 100mV
h = 1.5
Calculating again with h = 1 and the typical K-factor
value (K = 3.3μs) gives the absolute limit of dropout:
Therefore, V
IN
must be greater than 3.06V, even with
very large output capacitance, and a practical input volt-
age with reasonable output capacitance would be 3.47V.
Multi-Output Voltage Settings
(MAX1541 OUT1 Only)
While the main MAX1541 controller (OUT1) is optimized
to work with applications that require two dynamic out-
put voltages, it can produce three or more output volt-
ages if required by using discrete logic or a DAC.
Figure 15 shows an application circuit providing four
voltage levels using discrete logic. Switching resistors
in and out of the resistor network changes the voltage
at REFIN1. An edge-detection circuit is added to gen-
erate a 1μs pulse on GATE to trigger the fault blanking
and forced-PWM operation. When using PWM mode
(
SKIP
= V
CC
or open) on the main controller, the edge-
detection circuit is only required if fault blanking is
enabled. Otherwise, leave OD unconnected.
Active Bus Termination
(MAX1541 OUT1 Only)
Active-bus-termination power supplies generate a volt-
age rail that tracks a set reference. They are required to
source and sink current. DDR memory architecture
requires active bus termination. In DDR memory archi-
tecture, the termination voltage is set at exactly half the
memory supply voltage. Configure the main MAX1541
controller (OUT1) to generate the termination voltage
using a resistive voltage-divider at REFIN1. In such an
application, the main MAX1541 controller (OUT1) must
be kept in PWM mode (
SKIP
= V
CC
or open) in order
for it to source and sink current. Figure 16 shows the
main MAX1541 controller configured as a DDR termina-
tion regulator. Connect GATE and FBLANK to GND
when unused.
V
V
3 3
V
ns
s
μ
V
IN(MIN)
-
=
+
=
.
.
.
.
2 5
0 1
1
1 500
3 06
V
V
V
ns
s
V
IN(MIN)
-
=
+
.
3 0
=
.
.
.
.
2 5
1 5 500
0 1
1
3 47
μ
V
V
V
h
t
K
IN(MIN)
OUT
DROP1
OFF(MIN)
-
=
+
×
1
M
Dual Step-Down Controllers with Saturation
Protection, Dynamic Output, and Linear Regulator
______________________________________________________________________________________
41
Figure 15. Multi-Output Voltage Settings
MAX1541
REF
REFIN1
GND
GATE
R4
R3
A
C1
R2
R1
B
1000pF
1.5k
Ω
1000pF
1.5k
Ω
相關(guān)PDF資料
PDF描述
MAX1540AETJ Dual Step-Down Controllers with Saturation Protection, Dynamic Output, and Linear Regulator
MAX1543 TFT LCD DC-to-DC Converter with Operational Amplifiers
MAX1542 TFT LCD DC-to-DC Converter with Operational Amplifiers
MAX1542-MAX1543 TFT LCD DC-to-DC Converter with Operational Amplifiers
MAX1543ETP TFT LCD DC-to-DC Converter with Operational Amplifiers
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX1540AETJ+ 功能描述:DC/DC 開(kāi)關(guān)控制器 Dual Step-Down Ctlr w/Saturation Prot RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)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
MAX1540AETJ+T 功能描述:DC/DC 開(kāi)關(guān)控制器 Dual Step-Down Ctlr w/Saturation Prot RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)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
MAX1540ETJ 功能描述:DC/DC 開(kāi)關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)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
MAX1540ETJ+ 功能描述:DC/DC 開(kāi)關(guān)控制器 Dual Step-Down Ctlr RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)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
MAX1540ETJ+T 功能描述:DC/DC 開(kāi)關(guān)控制器 Dual Step-Down Ctlr RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)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
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*