参数资料
型号: MAX15026BEVKIT+
厂商: Maxim Integrated Products
文件页数: 15/23页
文件大小: 0K
描述: KIT EVAL FOR MAX15026
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 1
主要目的: DC/DC,步降
输出及类型: 1,非隔离
输出电压: 1.5V
电流 - 输出: 10A
输入电压: 5 ~ 16 V
稳压器拓扑结构: 降压
频率 - 开关: 600kHz
板类型: 完全填充
已供物品:
已用 IC / 零件: MAX15026B
MAX15026
Low-Cost, Small, 4.5V to 28V Wide Operating
Range, DC-DC Synchronous Buck Controller
requirements. Choose the small-signal components for
the error amplifier to achieve the desired closed-loop
bandwidth and phase margin.
To choose the appropriate compensation network type,
the power-supply poles and zeros, the zero crossover
frequency, and the type of the output capacitor must be
determined.
In a buck converter, the LC filter in the output stage intro-
duces a pair of complex poles at the following frequency:
Type II Compensation Network
(Figure 3)
If f ZO is lower than f O and close to f PO , the phase lead
of the capacitor ESR zero almost cancels the phase
loss of one of the complex poles of the LC filter around
the crossover frequency. Use a Type II compensation
network with a midband zero and a high-frequency
pole to stabilize the loop. In Figure 3, R F and C F intro-
duce a midband zero (f Z1 ). R F and C CF in the Type II
compensation network provide a high-frequency pole
f PO =
1
2 π × L OUT × C OUT
(f P1 ), which mitigates the effects of the output high-fre-
quency ripple.
Follow the instructions below to calculate the component
The output capacitor introduces a zero at:
values for the Type II compensation network in Figure 3:
f ZO =
1
2 π × ESR × C OUT
1) Calculate the gain of the modulator (GAIN MOD ),
comprised of the regulator’s pulse-width modulator,
LC filter, feedback divider, and associated circuitry
at the crossover frequency:
where ESR is the equivalent series resistance of the
×
output capacitor.
The loop-gain crossover frequency (f O ), where the loop
gain equals 1 (0dB) should be set below 1/10th of the
GAIN MOD =
V IN ESR
V RAMP ( 2 π × f O × L OUT )
×
V FB
V OUT
f O ≤ SW
switching frequency:
f
10
Choosing a lower crossover frequency reduces the
effects of noise pick-up into the feedback loop, such as
jittery duty cycle.
To maintain a stable system, two stability criteria must
be met:
1) The phase shift at the crossover frequency f O , must
be less than 180°. In other words, the phase margin
of the loop must be greater than zero.
2) The gain at the frequency where the phase shift is
-180° (gain margin) must be less than 1.
where V IN is the input voltage of the regulator, V RAMP is
the amplitude of the ramp in the pulse-width modulator,
V FB is the FB input voltage set-point (0.591V typically,
see the Electrical Characteristics table), and V OUT is
the desired output voltage.
The gain of the error amplifier (GAIN EA ) in midband fre-
quencies is:
GAIN EA = g M x R F
where g M is the transconductance of the error amplifier.
The total loop gain, which is the product of the modula-
tor gain and the error amplifier gain at f O , is 1.
GAIN MOD × GAIN EA = 1
So:
× × g M F = 1
× R
Maintain a phase margin of around 60° to achieve a
robust loop stability and well-behaved transient
response.
V IN
V RAMP
×
ESR
( 2 π × f O × L OUT )
V FB
V OUT
× ( 2 π × f × L ) × V
R F = RAMP O OUT OUT
When using an electrolytic or large-ESR tantalum output
capacitor the capacitor ESR zero f ZO typically occurs
between the LC poles and the crossover frequency f O
(f PO < f ZO < f O ). Choose Type II (PI—proportional-inte-
gral) compensation network.
When using a ceramic or low-ESR tantalum output
capacitor, the capacitor ESR zero typically occurs
Solving for R F :
V
V FB × V IN × g M × ESR
2) Set a midband zero (f Z1 ) at 0.75 x f PO (to cancel
one of the LC poles):
above the desired crossover frequency f O , that is f PO <
f O < f ZO . Choose Type III (PID—proportional, integral,
and derivative) compensation network.
Maxim Integrated
f Z 1 =
1
2 π × R F × C F
= 0 . 75 × f PO
15
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MAX15026BEVKIT+ 功能描述:电源管理IC开发工具 MAX15026B Eval Kit RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
MAX15026CATD+ 功能描述:DC/DC 开关控制器 4.5-28V Synchronous Buck 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
MAX15026CATD+T 功能描述:DC/DC 开关控制器 4.5-28V Synchronous Buck 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
MAX15026CETD+ 功能描述:DC/DC 开关控制器 4.5-28V Synchronous Buck 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
MAX15026CETD+G1D 制造商:Maxim Integrated Products 功能描述:LOW-COST, SMALL, 4.5V TO 28V WIDE OPERATING RANGE, DC-DC SYN - Rail/Tube