- 您现在的位置：买卖IC网 > PDF目录383329 > MAX1626ESA (MAXIM INTEGRATED PRODUCTS INC) 5V/3.3V or Adjustable, 100% Duty-Cycle, High-Efficiency, Step-Down DC-DC Controllers PDF资料下载
参数资料
| 型号： | MAX1626ESA |
| 厂商： | MAXIM INTEGRATED PRODUCTS INC |
| 元件分类： | 稳压器 |
| 英文描述： | 5V/3.3V or Adjustable, 100% Duty-Cycle, High-Efficiency, Step-Down DC-DC Controllers |
| 中文描述： | 0.05 A SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, PDSO8 |
| 封装： | 0.150 INCH, MS-012A, SOIC-8 |
| 文件页数： | 11/16页 |
| 文件大小： | 185K |
| 代理商： | MAX1626ESA |
Diode S elec tion
The MAX1626/MAX1627’s high switching frequency
demands a high-speed rectifier. Schottky diodes, such
as the 1N5817–1N5822 family or surface-mount equiva-
lents, are recommended. Ultra-high-speed rectifiers
with reverse recovery times around 50ns or faster, such
as the MUR series, are acceptable. Make sure that the
diode’s peak current rating exceeds the peak current
limit set by R
SENSE
, and that its breakdown voltage
exceeds V+. Schottky diodes are preferred for heavy
loads due to their low forward voltage, especially in
low-voltage applications. For high-temperature applica-
tions, some Schottky diodes may be inadequate due to
their high leakage currents. In such cases, ultra-high-
speed rectifiers are recommended, although a Schottky
diode with a higher reverse voltage rating can often
provide acceptable performance.
Capac itor S elec tion
Choose filter capacitors to service input and output
peak currents with acceptable voltage ripple.
Equivalent series resistance (ESR) in the capacitor is a
major contributor to output ripple, so low-ESR capaci-
tors are recommended. Sanyo OS-CON capacitors are
best, and low-ESR tantalum capacitors are second
best. Low-ESR aluminum electrolytic capacitors are tol-
erable, but do not use standard aluminum electrolytic
capacitors.
Voltage ripple is the sum of contributions from ESR and
the capacitor value:
V
RIPPLE
≈
V
RIPPLE ESR
To simplify selection, assume initially that two-thirds of
the ripple results from ESR and one-third results from
capacitor value. Voltage ripple as a consequence of
ESR is approximated by:
Estimate input and output capacitor values for given
voltage ripple as follows:
LI
IN
RIPPLE CIN IN
1
2
,
where I
L
is the change in inductor current (around
0.5I
PEAK
under moderate loads).
These equations are suitable for initial capacitor selec-
tion; final values should be set by testing a prototype or
evaluation kit. When using tantalum capacitors, use
good soldering practices to prevent excessive heat
from damaging the devices and increasing their ESR.
Also, ensure that the tantalum capacitors’ surge-current
ratings exceed the start-up inrush and peak switching
currents.
Pursuing output ripple lower than the error compara-
tor’s hysteresis (0.5% of the output voltage) is not prac-
tical, since the MAX1626/MAX1627 will switch as
needed, until the output voltage crosses the hysteresis
threshold. Choose an output capacitor with a working
voltage rating higher than the output voltage.
The input filter capacitor reduces peak currents drawn
from the power source and reduces noise and voltage
ripple on V+ and CS, caused by the circuit’s switching
action. Use a low-ESR capacitor. Two smaller-value
low-ESR capacitors can be connected in parallel for
lower cost. Choose input capacitors with working volt-
age ratings higher than the maximum input voltage.
Place a surface-mount ceramic capacitor very close to
V+ and GND, as shown in Figure 7. This capacitor
bypasses the MAX1626/MAX1627, and prevents spikes
and ringing on the power source from obscuring the
C
V
C
LI
V
V
V
V
L
OUT
L
RIPPLE COUT OUT
IN
IN
OUT
=
=
1
2
2
,
2
V
RIPPLE,ESR
≈
(
)
R
ESRIPEAK
+
,
,
V
RIPPLE C
M
5V /3.3V or Adjustable, 100% Duty-Cyc le,
High-Effic ienc y, S tep-Down DC-DC Controllers
Table 2. Component Suppliers
______________________________________________________________________________________
11
COMPANY
PHONE
(803) 946-0690
or
(800) 282-4975
(847) 639-6400
(516) 241-7876
(605) 668-4131
FAX
AVX
USA
(803) 626-3123
Coilcraft
Coiltronics
Dale
International
Rectifier
IRC
Motorola
Nichicon
USA
USA
USA
(847) 639-1469
(516) 241-9339
(605) 665-1627
USA
(310) 322-3331
(310) 322-3332
USA
USA
USA
J apan
USA
J apan
USA
J apan
(512) 992-7900
(602) 303-5454
(847) 843-7500
81-7-5231-8461
(805) 867-2555
81-3-3494-7411
(619) 661-6835
81-7-2070-6306
(408) 988-8000
or
(800) 554-5565
(603) 224-1961
(847) 956-0666
81-3-3607-5111
(512) 992-3377
(602) 994-6430
(847) 843-2798
81-7-5256-4158
(805) 867-2698
81-3-3494-7414
(619) 661-1055
81-7-2070-1174
Nihon
Sanyo
Siliconix
USA
(408) 970-3950
Sprague
Sumida
USA
USA
J apan
(603) 224-1430
(847) 956-0702
81-3-3607-5144
United
Chemi-Con
USA
(714) 255-9500
(714) 255-9400
相关PDF资料 |
PDF描述 |
|---|---|
| MAX1627ESA | 5V/3.3V or Adjustable, 100% Duty-Cycle, High-Efficiency, Step-Down DC-DC Controllers |
| MAX1626-MAX1627 | 5V/3.3V or Adjustable, 100% Duty-Cycle, High-Efficiency, Step-Down DC-DC Controllers |
| MAX1630 | Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers |
| MAX1631 | Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers |
| MAX1631CAI | Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX1626ESA+ | 功能描述:DC/DC 开关控制器 5/3.3V or Adjustable 100% Duty Cycle RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1626ESA+T | 功能描述:DC/DC 开关控制器 5/3.3V or Adjustable 100% Duty Cycle RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1626ESA-T | 功能描述:DC/DC 开关控制器 5/3.3V or Adjustable 100% Duty Cycle RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1626EVKIT | 功能描述:DC/DC 开关控制器 3V/3.3V 100% Duty-Cycle High-Efficiency Step-Down DC-DC Controller RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
| MAX1626EVKIT-SO | 功能描述:DC/DC 开关控制器 Evaluation Kit for the MAX1626 MAX1627 RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK |
发布紧急采购，3分钟左右您将得到回复。