- 您现在的位置：买卖IC网 > PDF目录1847 > MAX8540EEE+T (Maxim Integrated Products)IC REG CTRLR PWM CM 16-QSOP PDF资料下载
参数资料
| 型号： | MAX8540EEE+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 10/16页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR PWM CM 16-QSOP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| PWM 型： | 电流模式 |
| 输出数： | 1 |
| 频率 - 最大： | 1MHz |
| 占空比： | 82% |
| 电源电压： | 7.6 V ~ 18 V |
| 降压： | 无 |
| 升压： | 无 |
| 回扫： | 是 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 是 |
| Cuk： | 无 |
| 隔离： | 是 |
| 工作温度： | -40°C ~ 85°C |
| 封装/外壳： | 16-SSOP（0.154"，3.90mm 宽） |
| 包装： | 带卷 (TR) |
Synchronizable, High-Frequency Current- and
Voltage-Mode PWM Controllers for Isolated Supplies
The MAX8540/MAX8541 also synchronize with an
external oscillator. Drive FREQ/SYNC with a square
wave through a series diode with a positive pulse width
V IN
36V TO 76V
of at least 200ns and a minimum pulse amplitude of 3V,
plus the V F of the external diode. Alternatively, a 1.5V
C1
C2
C3
level-shifted external clock can be applied without the
series diode. The maximum duty cycle of the external
signal allowed is 55%. The MAX8540/MAX8541 syn-
chronize to frequencies between 200kHz and 1MHz;
however, the signal must be within ± 30% of the fre-
quency set by the external resistor at FREQ/SYNC.
RA
Maximum Duty Cycle
Set the maximum duty cycle at the minimum system
input voltage (V IN(MIN) ) connecting a resistor from
MAXDTY to GND. The maximum duty cycle is inversely
proportional to the voltage at UV. As the voltage on UV
increases, the duty cycle decreases. The maximum
RC
RB
OV
UV
MAX8541
duty cycle is internally limited to 80% at all switching
frequencies. The MAXDTY resistor is determined as:
R MAXDTY =
D MAX × (97.6 × 10 3 )
60
Figure 1. A Method to Set UV and OV Thresholds
where dV RAMP /dt = 2.5V(f S ), R SUM = 25k ? , N is the
where D MAX is the desired maximum duty cycle.
The range of valid resistor values for R MAXDTY is from
24.3k ? to 130k ? .
N-Channel MOSFET Driver
The DRV output drives an N-channel MOSFET in low-
power applications. In high-power applications, the gate
turns ratio of the primary to secondary, L1 is the output
inductance, V OUT is the output voltage, f S is the switch-
ing frequency, and R CS is the current-sense resistance.
For applications where a diode is used in the output
instead of the synchronous rectifier, the slope compen-
sation resistor is then equal to:
driver internal to the MAX8540/MAX8541 may not be
capable of driving the external MOSFET efficiently and
an external gate driver may be required. In this situation,
SCF = N
V OUT + V F
L 1
R CS
connect DRV to the input of the external gate driver.
dV RAMP R SUM
Slope Compensation (MAX8540)
The MAX8540 is a current-mode device and requires
slope compensation for proper operation. To provide
R SCOMP =
×
dt 2 SCF
slope compensation, connect a resistor from SCOMP to
GND (R SCOMP ). The value of R SCOMP is determined as
follows.
For applications using a synchronous rectifier in the
output, set the slope compensation equal to the nega-
tive slope of the output inductor. R SCOMP is equal to:
where dV RAMP /dt = 2.5V(f S ),R SUM = 25k ? , N is the turns
ratio of the primary to secondary, L1 is the output induc-
tance, V OUT is the output voltage, V F is the diode voltage,
f S is the switching frequency, and R CS is the current-
sense resistance.
Voltage-Ramp Amplitude (MAX8541)
SCF = N
V OUT
L 1
R CS
The MAX8541 is a voltage-mode device and features
adjustable voltage ramp. Connect a resistor from
PRAMP to GND (R PRAMP ) to set the voltage-ramp
magnitude, V M .
dV RAMP R SUM
R SCOMP =
×
dt 2 SCF
V M = 1 . 25 V
25 k ?
R PRAMP
10
______________________________________________________________________________________
相关PDF资料 |
PDF描述 |
|---|---|
| MAX8545EUB+T | IC REG CTRLR BUCK PWM VM 10-UMAX |
| MAX8550AETI+T | IC PWR SUP DDR INTEG 28TQFN |
| MAX8550ETI+ | IC PWR SUP DDR INTEG 28TQFN |
| MAX8553EEE+T | IC CNTRLR BUCK PWM 16-QSOP |
| MAX8555EUB+ | IC CNTRLR MOSFET ORING 10-UMAX |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX8541EEE | 功能描述:电压模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel |
| MAX8541EEE+ | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX8541EEE-T | 功能描述:电压模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel |
| MAX8543EEE | 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 |
| MAX8543EEE+ | 功能描述:电流型 PWM 控制器 Step-Down Controller RoHS:否 制造商:Texas Instruments 开关频率:27 KHz 上升时间: 下降时间: 工作电源电压:6 V to 15 V 工作电源电流:1.5 mA 输出端数量:1 最大工作温度:+ 105 C 安装风格:SMD/SMT 封装 / 箱体:TSSOP-14 |
发布紧急采购，3分钟左右您将得到回复。