- 您现在的位置：买卖IC网 > PDF目录15138 > MAX1993ETG+ (Maxim Integrated Products)IC REG CTRLR BUCK PWM CM 24-TQFN PDF资料下载
参数资料
| 型号： | MAX1993ETG+ |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 22/36页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BUCK PWM CM 24-TQFN |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 75 |
| 系列： | Quick-PWM™ |
| PWM 型： | 电流模式 |
| 输出数： | 1 |
| 频率 - 最大： | 600kHz |
| 占空比： | 100% |
| 电源电压： | 4.5 V ~ 5.5 V |
| 降压： | 是 |
| 升压： | 无 |
| 回扫： | 无 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 无 |
| Cuk： | 无 |
| 隔离： | 无 |
| 工作温度： | -40°C ~ 85°C |
| 封装/外壳： | 24-WFQFN 裸露焊盘 |
| 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页第18页第19页第20页第21页当前第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页
Quick-PWM Step-Down Controllers with Inductor
Saturation Protection and Dynamic Output Voltages
Power-Good Output (PGOOD)
PGOOD is the open-drain output for a window com-
parator that continuously monitors the output. PGOOD
is actively held low in shutdown and during soft-start.
After the digital soft-start terminates, PGOOD becomes
high impedance as long as the output voltage is within
±10% of the nominal regulation voltage set by FB.
When the output voltage drops 10% below or rises 10%
above the nominal regulation voltage, the MAX1992/
MAX1993 pull PGOOD low. Any fault condition forces
PGOOD low until the fault latch is cleared by toggling
SHDN or cycling V CC power below 1V. For logic level
output voltages, connect an external pullup resistor
between PGOOD and V CC . A 100k Ω resistor works well
in most applications.
Note that the PGOOD window detector is completely
independent of the overvoltage and undervoltage pro-
tection fault detectors.
Fault Blanking (MAX1993 FBLANK)
The MAX1993 automatically enters forced-PWM opera-
tion during all dynamic output voltage transitions (GATE
transition detected) in order to ensure fast, accurate
transitions. FBLANK determines how long the MAX1993
maintains forced-PWM operation (Table 5)—at least
140μs (FBLANK = V CC ), 90μs (FBLANK = open or
GND), or 40μs (FBLANK = REF).
When fault blanking is enabled (FBLANK = V CC , open,
or REF), the MAX1993 also disables the overvoltage
and undervoltage fault protection and forces PGOOD
to a high-impedance state during the transition period
selected by FBLANK (Table 5). This prevents fault pro-
tection from latching off the controller and the PGOOD
signal from going low when the output voltage change
( Δ V OUT ) cannot occur as fast as the REFIN voltage
change ( Δ V REFIN ).
Table 5. FBLANK Configuration Table
Shutdown and Output Discharge
When output discharge is enabled (OVP/UVP = V CC or
open) and SHDN is pulled low, or the output undervolt-
age fault latch is set (OVP/UVP = V CC or REF), the
MAX1992/MAX1993 discharge the output through an
internal 10 Ω switch to ground. While the output is dis-
charging, DL is forced low and the PWM controller is
disabled, but the reference remains active to provide
an accurate threshold. Once the output voltage drops
below 0.3V, the MAX1992/MAX1993 shut down the ref-
erence and pull DL high, effectively clamping the out-
put and LX switching node to ground.
When output discharge is disabled (OVP/UVP = REF or
GND), the controller does not actively discharge the out-
put, and the DL driver remains low. Under these condi-
tions, the output discharge rate is determined by the load
current and output capacitance.
The controller detects and latches the discharge mode
state set by OVP/UVP on startup.
Fault Protection
The MAX1992/MAX1993 provide over/undervoltage
fault protection. Drive OVP/UVP to enable and disable
fault protection as shown in Table 6. Once activated,
the controller continuously monitors the output for
undervoltage and overvoltage fault conditions.
Overvoltage Protection (OVP)
When the output voltage rises above 116% of the nomi-
nal regulation voltage and OVP is enabled (OVP/UVP =
V CC or open), the OVP circuit sets the fault latch, shuts
down the PWM controller, and immediately pulls DH low
and forces DL high. This turns on the synchronous rectifi-
er MOSFET with 100% duty, rapidly discharging the out-
put capacitor and clamping the output to ground. Note
that immediately latching DL high can cause the output
voltage to go slightly negative due to energy stored in
the output LC at the instant the OVP occurs. If the load
cannot tolerate a negative voltage, place a power
Schottky diode across the output to act as a reverse-
FBLANK
V CC
Open
REF
GND
FAULT BLANKING
Enabled
Enabled
Enabled
Disabled
MINIMUM FORCED-
PWM DURATION (μs)
140
90
40
90
polarity clamp. If the condition that caused the overvolt-
age persists (such as a shorted high-side MOSFET), the
battery fuse blows. OVP is ignored when transitions are
detected on GATE (MAX1993 only, FBLANK enabled).
Toggle SHDN or cycle V CC power below 1V to clear the
fault latch and restart the controller.
OVP is disabled when OVP/UVP is connected to REF or
GND (Table 6).
22
______________________________________________________________________________________
相关PDF资料 |
PDF描述 |
|---|---|
| SLP392M050E1P3 | CAP ALUM 3900UF 50V 20% SNAP |
| ECC40DRTH | CONN EDGECARD 80POS DIP .100 SLD |
| MAX1744EUB/V+ | IC REG CTRLR BUCK PWM 10-UMAX |
| SLPX681M180C3P3 | CAP ALUM 680UF 180V 20% SNAP |
| EBC65DRTF | CONN EDGECARD 130PS DIP .100 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX1993ETG+ | 功能描述:电压模式 PWM 控制器 Step-Down w/Inductor 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 |
| MAX1993ETG+T | 功能描述:电压模式 PWM 控制器 Step-Down w/Inductor 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 |
| MAX1993ETG+TG40 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX1993ETG-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 |
| MAX1993EVKIT | 制造商:Maxim Integrated Products 功能描述:EVALUATION KIT FOR THE MAX1992 MAX1993 - Bulk |
发布紧急采购，3分钟左右您将得到回复。