- 您现在的位置：买卖IC网 > PDF目录13527 > MAX1709EUI+T (Maxim Integrated Products)IC REG BST 3.3/5V/ADJ 4A 28TSSOP PDF资料下载
参数资料
| 型号： | MAX1709EUI+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 11/15页 |
| 文件大小： | 0K |
| 描述： | IC REG BST 3.3/5V/ADJ 4A 28TSSOP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 类型： | 升压（升压） |
| 输出类型： | 两者兼有 |
| 输出数： | 1 |
| 输出电压： | 3.3V，5V，可调 |
| 输入电压： | 0.7 V ~ 5 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 350kHz ~ 1MHz |
| 电流 - 输出： | 4A |
| 同步整流器： | 无 |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 28-SOIC（0.173"，4.40mm 宽）裸露焊盘 |
| 包装： | 带卷 (TR) |
| 供应商设备封装： | 28-TSSOP 裸露焊盘 |
4A, Low-Noise, High-Frequency,
Step-Up DC-DC Converter
Output Filter Capacitors (C6, C7)
ON/OFF
270k
MAX1709
ONB
ONA
μ C
V DD
I/O
I/O
The output filter capacitor ESR must be kept under
15m Ω for stable operation. Two parallel 150μF polymer
capacitors (Panasonic EEFUE0J151R) typically exhibit
5m Ω of ESR. This translates to approximately 35mV of
output ripple at 7A switch current. Bypass the
MAX1709 IC supply input (OUT) with a 0.1μF ceramic
capacitor to GND and connect a 2 Ω series resistor to
OUT (R2, as shown in Figure 1).
270k
0.1 μ F
Figure 5. Momentary Pushbutton On-Off Switch
V D = forward voltage drop of the Schottky diode at I LIM
current
V OUT = output voltage
D' = (V IN ) / (V OUT + V D ), assuming switch voltage drop
is negligible
f = switching frequency
L1 = inductor value
I LIM = minimum value of switch current limit from Elec-
trical Characteristics or set by R SET/LIM .
Diode Selection (D1)
The MAX1709’s high switching frequency demands a
high-speed rectifier. Schottky diodes, such as the
MBRD1035CTL or STPS8L30B (Table 3), are recom-
mended. The diode’s current rating must exceed the
maximum load current, and its breakdown voltage must
exceed V OUT . The diode must be placed within 10mm
of the LX switching node and the output filter capacitor.
The diode also must be able to dissipate the power cal-
culated by the following equation:
P DIODE = I OUT V D
where I OUT is the average load current and V D is the
Power Dissipation
The MAX1709 output current may be more limited by
package power dissipation than by the current rating of
the on-chip switch. For pulsed loads, output currents of
4 Amps or more can be supplied with either the
MAX1709EUI+ or MAX1709ESE, but the RMS (or ther-
mal) limit of the MAX1709ESE is lower (6A RMS ) than
that of the MAX1709EUI+ (10A RMS ). Continuous output
current depends on the input and output voltage, oper-
ating temperature, and external components.
The major components of the MAX1709 dissipated
power (P D , i.e., power dissipated as heat in the IC and
NOT delivered to the load) are:
1) Internal switch conduction losses - P SW
2) Internal switch transition losses - P TRAN
3) Internal capacitive losses - P CAP
These are losses that directly dissipate heat in the
MAX1709, but keep in mind that other losses, such as
those in the external diode and inductor, increase input
power by reducing overall efficiency, and so indirectly
contribute to MAX1709 heating.
Approximate equations for the loss terms are as fol-
lows. Values in {} are example values for a 3.3V input,
4V output, 4A design.
A conservative efficiency estimate for the MAX1709
boosting from 3.3V to 5V at 4A is 81%. Total estimated
power loss is then:
diode forward voltage at the peak switch current.
P LOSS = (P OUT / 0.81) - P OUT
{4.7W}
Capacitor Selection
Input Bypass Capacitors (C1, C2)
Two 150μF, low-ESR tantalum input capacitors will
reduce peak currents and reflected noise due to induc-
tor current ripple. Lower ESR allows for lower input rip-
ple current, but combined ESR values up to 50m Ω are
acceptable. Smaller ceramic capacitors may also be
The total loss consists of:
Diode Loss = D’ x I SW x V D {2.5W}
Inductor Loss (resistive loss + dynamic loss
estimate) {0.58W}
External Capacitive Loss = (1 - D’) x I SW 2 x
R CAP-ESR (ESR est. = 10m Ω ) {0.27W}
used for light loads or in applications that can tolerate
higher input current ripple.
MAX1709 Internal Loss, P D(MAX1709)
{1.35W}
______________________________________________________________________________________
11
相关PDF资料 |
PDF描述 |
|---|---|
| RBC15DRAN-S734 | CONN EDGECARD 30POS .100 R/A PCB |
| MAX1709ESE+T | IC REG BST 3.3V/5V/ADJ 4A 16SOIC |
| MAX759EWE+T | IC REG INV ADJ 0.3A 16SOIC |
| MAX736EWE+T | IC REG INV -12V 125MA 16SOIC |
| RBC15DRAH-S734 | CONN EDGECARD 30POS .100 R/A PCB |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX1709EVKIT | 功能描述:直流/直流开关转换器 Evaluation Kit for the MAX1709 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| MAX170ACPA | 功能描述:模数转换器 - ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32 |
| MAX170ACPA+ | 功能描述:模数转换器 - ADC 12-Bit 115ksps 5.25V- Precision ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32 |
| MAX170ACWE | 功能描述:模数转换器 - ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32 |
| MAX170ACWE+ | 功能描述:模数转换器 - ADC Serial Output 5.6 Micro Seconds 12-Bit ADC RoHS:否 制造商:Texas Instruments 通道数量:2 结构:Sigma-Delta 转换速率:125 SPs to 8 KSPs 分辨率:24 bit 输入类型:Differential 信噪比:107 dB 接口类型:SPI 工作电源电压:1.7 V to 3.6 V, 2.7 V to 5.25 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-32 |
发布紧急采购，3分钟左右您将得到回复。