- 您现在的位置：买卖IC网 > PDF目录1843 > MAX5069CAUE+ (Maxim Integrated Products)IC REG CTRLR ISO PWM CM 16-TSSOP PDF资料下载
参数资料
| 型号： | MAX5069CAUE+ |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 15/19页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR ISO PWM CM 16-TSSOP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 96 |
| PWM 型： | 电流模式 |
| 输出数： | 2 |
| 频率 - 最大： | 2.5MHz |
| 占空比： | 100% |
| 电源电压： | 10.8 V ~ 24 V |
| 降压： | 无 |
| 升压： | 无 |
| 回扫： | 无 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 无 |
| Cuk： | 无 |
| 隔离： | 是 |
| 工作温度： | -40°C ~ 125°C |
| 封装/外壳： | 16-TSSOP（0.173"，4.40mm）裸露焊盘 |
| 包装： | 管件 |
High-Frequency, Current-Mode PWM Controller
with Accurate Oscillator and Dual FET Drivers
C FLTINT ? FLTINT SH
V OUT = ? 1 +
? x V REF
R FLTINT ?
165 × 10 ? 6
× C
Note that cycle-by-cycle current limiting is provided at
all times by CS with a threshold of 314mV (typ). The
fault-integration circuit forces a 60μA current onto
FLTINT each time that the current-limit comparator is
tripped (see the Functional Diagram ). Use the following
formula to calculate the value of the capacitor neces-
sary for the desired shutdown time of the circuit:
I x t
2 . 8 V
where I FLTINT = 60μA, t SH is the desired fault-integra-
tion time during which current-limit events from the cur-
rent-limit comparator are ignored. For example, a 0.1μF
capacitor gives a fault-integration time of 4.7ms.
This is an approximate formula. Some testing may be
required to fine-tune the actual value of the capacitor. To
calculate the recovery time, use the following formula:
t RT
0 . 595 × C FLTINT
where t RT is the desired recovery time.
Choose t RT = 10 x t SH . Typical values for t SH range from
a few hundred microseconds to a few milliseconds.
Soft-Start
The MAX5069 soft-start feature allows the load voltage
to ramp up in a controlled manner, eliminating output-
voltage overshoot. Soft-start begins after UVLO is
deasserted. The voltage applied to the noninverting
node of the amplifier ramps from 0 to 1.23V in 2047
oscillator clock cycles (soft-start timeout period). Unlike
other devices, the MAX5069 reference voltage to the
internal amplifier is soft-started. This method results in
superior control of the output voltage under heavy- and
light-load conditions.
Internal Regulators
Two internal linear regulators power the MAX5069 inter-
nal and external control circuits. V CC powers the exter-
nal N-channel MOSFETs and is internally set to
approximately 9.5V. The REG5 5V regulator has a 1mA
sourcing capability and may be used to provide power
Error Amplifier
The MAX5069 includes an internal error amplifier that
can regulate the output voltage in the case of a noniso-
lated power supply ( Figure 1). Calculate the output volt-
age using the following equation:
? R 9 ?
? R 10 ?
where V REF = 1.23V. The amplifier’s noninverting input
internally connects to a digital soft-start reference voltage.
This forces the output voltage to come up in an orderly
and well-defined manner under all load conditions.
Slope Compensation
The MAX5069 uses an internal-ramp generator for
slope compensation. The internal-ramp signal resets at
the beginning of each cycle and slews at the rate pro-
grammed by the external capacitor connected at
SCOMP and the resistor at RT. Adjust the MAX5069
slew rate up to 90mV/μs using the following equation:
SR = ( mV / μ s )
R RT SCOMP
where R RT is the external resistor at RT that sets the oscil-
lator frequency and C SCOMP is the capacitor at SCOMP.
PWM Comparator
The PWM comparator uses the instantaneous current,
the error amplifier, and the slope compensation to
determine when to switch NDRVA and NDRVB off. In
normal operation, the N-channel MOSFETs turns off
when:
I PRIMARY x R CS > V EA – V OFFSET - V SCOMP
where I PRIMARY is the current through the N-channel
MOSFETs, V EA is the output voltage of the internal
amplifier, V OFFSET is the 1.6V internal DC offset, and
V SCOMP is the ramp function starting at zero and slew-
ing at the programmed slew rate (SR). When using the
MAX5069 in a forward-converter configuration, the fol-
lowing conditions must be met to avoid current-loop
subharmonic oscillations:
to external circuitry. Bypass V CC and REG5 with 1μF
and 0.1μF high quality capacitors, respectively. Use
lower value ceramics in parallel to bypass other
N S
N P
×
K × R CS × V OUT
L
= SR
unwanted noise signals. Bootstrapped operation
requires startup through a bleed resistor. Do not exces-
sively load the regulators while the MAX5069 is in the
power-up mode. Overloading the outputs may cause
the MAX5069 to fail upon startup.
where K = 0.75 and N S and N P are the number of turns
on the secondary and primary side of the transformer,
respectively. L is the secondary filter inductor. When
optimally compensated, the current loop responds to
input-voltage transients within one cycle.
______________________________________________________________________________________
15
相关PDF资料 |
PDF描述 |
|---|---|
| MAX5070AAUA+T | IC REG CTRLR FLYBK DIV ISO 8UMAX |
| MAX5072ETJ+T | IC REG BUCK BST ADJ 1A/2A 32TQFN |
| MAX5073ATI+ | IC REG BUCK BST ADJ 1A/2A 28TQFN |
| MAX5080ATE+T | IC REG BUCK ADJ 1A 16TQFN |
| MAX5083ATE+ | IC REG BUCK ADJ 1.5A 16TQFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX5069CAUE+ | 功能描述:电流型 PWM 控制器 High-Frequency Current-Mode PWM 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 |
| MAX5069CAUE+T | 功能描述:电流型 PWM 控制器 High-Frequency Current-Mode PWM 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 |
| MAX5069CAUE-T | 功能描述:电流型 PWM 控制器 High-Frequency Current-Mode PWM 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 |
| MAX5069D | 制造商:MAXIM 制造商全称:Maxim Integrated Products 功能描述:High-Frequency, Current-Mode PWM Controller with Accurate Oscillator and Dual FET Drivers |
| MAX5069DAUE | 功能描述:电流型 PWM 控制器 High-Frequency Current-Mode PWM 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。