- 您现在的位置：买卖IC网 > PDF目录20674 > MAX1632AEAI+ (Maxim Integrated)IC REG TRPL BCK/LINEAR 28-SSOP PDF资料下载
参数资料
| 型号： | MAX1632AEAI+ |
| 厂商： | Maxim Integrated |
| 文件页数： | 18/29页 |
| 文件大小： | 0K |
| 描述： | IC REG TRPL BCK/LINEAR 28-SSOP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 46 |
| 拓扑： | 降压（降压）同步（2），线性（LDO）（1） |
| 功能： | 任何功能 |
| 输出数： | 3 |
| 频率 - 开关： | 200kHz ~ 300kHz |
| 电压/电流 - 输出 1： | 控制器 |
| 电压/电流 - 输出 2： | 控制器 |
| 电压/电流 - 输出 3： | 12V，120mA |
| 带 LED 驱动器： | 无 |
| 带监控器： | 无 |
| 带序列发生器： | 是 |
| 电源电压： | 4.2 V ~ 30 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 28-SSOP（0.209"，5.30mm 宽） |
| 供应商设备封装： | 28-SSOP |
| 包装： | 管件 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页当前第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页
Multi-Output, Low-Noise Power-Supply
Controllers for Notebook Computers
rate output of more than 120mA is needed, an external
pass transistor can be added. Figure 6’s circuit delivers
more than 200mA. Total output current is constrained
by the V+ input voltage and the transformer primary
load (see Maximum 15V V DD Output Current vs.
Supply Voltage graphs in the Typical Operating
Characteristics ).
__________________Design Procedure
The three predesigned 3V/5V standard application cir-
cuits (Figure 1 and Table 1) contain ready-to-use solu-
tions for common application needs. Also, two standard
flyback transformer circuits support the 12OUT linear
regulator in the Applications Information section. Use
the following design procedure to optimize these basic
schematics for different voltage or current require-
ments. Before beginning a design, firmly establish the
following:
? Maximum input (battery) voltage, V IN(MAX) . This
value should include the worst-case conditions,
such as no-load operation when a battery charger
or AC adapter is connected but no battery is
installed. V IN(MAX) must not exceed 30V.
intended mainly for high-efficiency, battery-powered
applications. Refer to Appendix A in Maxim’s Battery
Management and DC-DC Converter Circuit Collection
for crossover-point and discontinuous-mode equations.
Discontinuous conduction doesn’t affect normal Idle
Mode operation.
Three key inductor parameters must be specified:
inductance value (L), peak current (I PEAK ), and DC
resistance (R DC ). The following equation includes a
constant, LIR, which is the ratio of inductor peak-to-
peak AC current to DC load current. A higher LIR value
allows smaller inductance, but results in higher losses
and higher ripple. A good compromise between size
and losses is found at a 30% ripple-current to load-
current ratio (LIR = 0.3), which corresponds to a peak
inductor current 1.15 times higher than the DC load
current:
V OUT ( V IN(MAX) - V OUT )
L =
V IN(MAX) x f x I OUT x LIR
where:
f = switching frequency, normally 200kHz or
?
Minimum input (battery) voltage, V IN(MIN) . This
should be taken at full load under the lowest battery
conditions. If V IN(MIN) is less than 4.2V, use an
external circuit to externally hold VL above the VL
undervoltage lockout threshold. If the minimum
input-output difference is less than 1.5V, the filter
capacitance required to maintain good AC load
regulation increases (see Low-Voltage Operation
300kHz
I OUT = maximum DC load current
LIR = ratio of AC to DC inductor current, typi-
cally 0.3; should be selected for >0.15
The nominal peak inductor current at full load is 1.15 x
I OUT if the above equation is used; otherwise, the peak
current can be calculated by:
section).
Inductor Value
I PEAK = I LOAD +
V OUT (V IN(MAX) - V OUT )
2 x f x L x V IN(MAX)
The exact inductor value is not critical and can be
freely adjusted to make trade-offs between size, cost,
and efficiency. Lower inductor values minimize size
and cost, but reduce efficiency due to higher peak-cur-
rent levels. The smallest inductor is achieved by lower-
ing the inductance until the circuit operates at the
border between continuous and discontinuous mode.
Further reducing the inductor value below this
crossover point results in discontinuous-conduction
operation even at full load. This helps lower output filter
capacitance requirements, but efficiency suffers due to
high I 2 R losses. On the other hand, higher inductor val-
ues mean greater efficiency, but resistive losses due to
extra wire turns will eventually exceed the benefit
gained from lower peak-current levels. Also, high
inductor values can affect load-transient response (see
the V SAG equation in the Low-Voltage Operation sec-
tion). The equations that follow are for continuous-con-
duction operation, since the MAX1630A family is
The inductor’s DC resistance should be low enough that
R DC x I PEAK < 100mV, as it is a key parameter for effi-
ciency performance. If a standard off-the-shelf inductor
is not available, choose a core with an LI 2 rating greater
than L x I PEAK 2 and wind it with the largest diameter
wire that fits the winding area. For 300kHz applications,
ferrite core material is strongly preferred; for 200kHz
applications, Kool-Mμ ? (aluminum alloy) or even pow-
dered iron is acceptable. If light-load efficiency is unim-
portant (in desktop PC applications, for example), then
low-permeability iron-powder cores, such as the
Micrometals type found in Pulse Engineering’s 2.1μH
PE-53680, may be acceptable even at 300kHz. For
high-current applications, shielded-core geometries,
such as toroidal or pot core, help keep noise, EMI, and
switching-waveform jitter low.
Kool-Mμ is a registered trademark of Magnetics Div., Spang & Co.
18
______________________________________________________________________________________
相关PDF资料 |
PDF描述 |
|---|---|
| ISL97519AIUZEVALZ | EVAL BOARD FOR ISL97519AIUZ |
| EEM25DCMI | CONN EDGECARD 50POS .156 SQ WW |
| MAX4210CEUA+T | IC CURRENT MONITOR 1.5% 8MSOP |
| VI-J62-CX-F2 | CONVERTER MOD DC/DC 15V 75W |
| MAX1999EEI+ | IC REG QD BCK/LINEAR SYNC 28QSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX1632AEAI+ | 功能描述:DC/DC 开关控制器 Multi-Out Low-Noise Power-Supply Ctlr 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 |
| MAX1632AEAI+T | 功能描述:DC/DC 开关控制器 Multi-Out Low-Noise Power-Supply Ctlr 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 |
| MAX1632AEAI-T | 功能描述:DC/DC 开关控制器 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 |
| MAX1632CAI | 功能描述:DC/DC 开关控制器 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 |
| MAX1632CAI+ | 制造商:Maxim Integrated Products 功能描述:DC DC CNTRLR DUAL-OUT STEP DOWN 4.2V TO 30V 28SSOP - Rail/Tube |
发布紧急采购，3分钟左右您将得到回复。