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2022-09-15 14:32:14
LM5041 level pwm controller
Function pack
Internal startup deviation regulator
TSSOP -6
Able-avairy line owl lock
WSON-16 (5x5 mm) Thermal enhancement type (UVLO) has adjustable magnetic stagnationcurrent mode control
LM5041 PWM controller contains all reference
internal error release large device
Realization The current FED or dual -mode overcurrent protection voltage feedback electric push -pull or bridge power converter.
The ""level"" topology of the frontier consumption is very suitable for
to program the programmable push and overlap with multiple output and higher power applications. The four control outputs of this LM5041 include: the control device (HD and LD) and push -pull control device
Internal 1.5A sliding door drive output (push -pull) during the antihypertensive stage. The push -pull output is a programmable soft start, and the frequency of the driver's antihypertensive switch is driven by the 50%rated duty cycle. The programmable oscillator has a synchronous function configuration to the specified overlapping time (for accurate reference current feedback applied) or two specified two specified two or prescribed. Turn off the heat shutdown (for voltage feed application). The MOSFET can be directly driven by the internal driver during the push -pull phase, and the buck phase requires an external drive like LM5102. LM5041 includes a telecommunications power converter high -voltage startup regulator, working within the wide input range of 15V to 100V. PWM controller multi -output power converter design is designed for high -speed performance, including the frequency range of the oscillator as high as 1 MM+42V automotive system transmission less than 100ns. Additional features include: lines of lines of voltage (UVLO), soft start, error amplifier, precision voltage reference and heat shutdown.
Standard font specifications are suitable scope. Vin u003d 48V, VCC u003d 10V, RT u003d 26.7K , RSET u003d 20K ), unless there is another instructions. (1)
(1) All restrictions are specified. During the production process, all electrical characteristics with room temperature restrictions are tested under the conditions of TA u003d TJ u003d 25 ° C. By associating the electrical characteristics and the temperature changes, and the statistical method is used to verify the heat limit and cold limit process process control. 
Electrical characteristics (continued)
The specifications of standard fonts are applicable to TJ u003d 25 ° C, black body specifications are suitable for full working joint temperaturescope. Vin u003d 48V, VCC u003d 10V, RT u003d 26.7K , RSET u003d 20K ), unless there is another instructions. (1)
Typical performance features 
Detailed operation description [123 ]
High -voltage startup regulator
LM5041 contains an internal high -voltage startup regulator, so you can connect to the input pin (VIN) directly to the line voltage. The internal current output of the regulator is limited to 15 mAh. When the power is powered, the regulator is activated and the current inputs the current to the external capacitor where the VCC pin is connected to the VCC pin. The capacitance range of the recommended VCC regulator is 0.1UF to 100UF. When the voltage on the VCC pin reaches 9V, the internal reference voltage (REF) reaches 5V adjustment nodes, and the controller output has been enabled. The antihypertensive output will be kept in a state, until the VCC drops to less than 7V or the circuit owl voltage lock detector indicates that the VIN is beyond the range. The push output continues to switch until the reference pin voltage drops to about 3V. In typical applications, the auxiliary transformer winding is connected to the VCC pin through diode. The winding must increase the VCC voltage to above 9.3V to cut off the internal startup regulator. Power supply from the auxiliary winding can improve efficiency and reduce the power consumption of the controller. The recommended capacitor range of VREF regulator output is 0.1UF to 10 Hualhi. The size of the external VCC capacitor must ensure that the capacitor is initially started. In the fault mode, when the variables are not activated, the external current consumption should limit the VCC line to make the power consumption in the startup regulator not exceed the power consumption of the maximum value controller. By connecting VCC, you can use external startup or other bias orbit instead of internal startup regulator andVIN tube feet are connected together and provide external bias voltage to the two tube feet.
Route underwriter
LM5041 contains the circuit of the circuit owl (UVLO). The working range of the converter from the external settings of the external settings of the VIN. The design of the sterilizer must ensure that when the vehicle recognition number (VIN) is within the required working range, the UVLO pin will be greater than 2.5V. If the voltage threshold is not satisfied, all the functions of the controller will be disabled, and the controller will enter a low power state and enter the current lt; 300 μA. ULVO's stagnation can enters the impedance of the settings point frequency splitter through the internal 20μA current source that is turned on or off. When exceeding the UVLO threshold, the current source is activated to immediately increase the voltage of the UVLO pin. When the UVLO pin is lower than the 2.5V threshold, the current source is closed, causing the voltage of the UVLO pin to decrease. The UVLO pin can also be used to achieve remote enable/disable functions. By short -circuit the UVLO pin to the ground, the converter can. The controller can also be disabled by a soft starting pin (SS). The controller will enter a low power. If the SS pin is forced to turn off the shutdown threshold below 0.45V, it will be closed.
Anti -voltage control output
LM5041 The maximum duty cycle of the LM5041 antihypertensive switch to ensure that each cycle is sufficiently closed to charge the self -lifting capacitor used in the high -voltage side grid drive. The buck switch is specified to turn off and the switch is opened simultaneously, each switching cycle is at least 250 nan seconds. Anti -voltage control output (LD and HD) is a buffer with a CMOS logic level of 0 to 5V. In any failure state or under pressure disconnection, the antihypertensive control output will default to HD LOW and LD high.
Push pull output
Push -pull output works continuously with a 50%rated duty cycle. Whether the significant feature of LM5041 can accurately configure the dead area (both closed) or overlap time (all open) push output on the complementary circuit. Overlap/dead zone time range from the resistor controller of the time pins connected to the upper time. The time pin keeps one end of the resistor at 2.5V. The other end of the resistor should be connected to the REF to perform the dead zone control settings, or to the GND for overlapping control. The polarity of the current is detected by LM5041. The size of the overlapping/stagnation time can be calculated as follows:
overlapping time (NS) u003d (3.66 x RSET) +7 overlap time is NS unit, RSET is connected to GND, RSET is K Zone Time (NS) u003d (3.69 X RSET) +21
The dead area is in NS, RSET is connected to REF, RSET is K To 100k
The current feedback power design requires a period of overlap to ensure that there is a continuous path for the lower -voltage inductor current. The voltage feedback design requires a dead zone time to ensure that the push transformer has no time to move the low -impedance source node. The condition provided by the push -pull output is greater than 3V.
Pulse width modulation comparator
PWM comparator compensate the slope to the slope slope signal with internal errors (compensation pins). The speed of this comparison is optimized to achieve the minimum controlled duty cycle. The polarity of the comparator enables the 0V on the compensation pins in the Buck stage.
error amplifier
A large high -gain broadband error amplifier provided in LM5041. The non -inverter input of the amplifier is connected to the 0.75V reference voltage. Reverse input to FB pins. In a non -isolation application, the power converter output is connected to the FB pin through the voltage. The loop compensation component is connected between the COMP and the FB pin. For most isolation applications, the error amplifier function is implemented on the secondary side of the converter, and the internal error placed is not used. This internal error amplifier is configured to open the leakage output, which can be connected to the ground by connecting the FB pin. The internal 5K the upper pull resistor between the 5V reference and compensation can be used as a optocoupler in the isolation application.
current limit/current influenza response
LM5041 includes two -level overcurrent protection. If the voltage on the CS pin exceeds 0.5V anti -voltage rate, the duty cycle is terminated (circulating current limit). If the voltage of the CS pin exceeds 0.5V threshold exceeding 0.6V, the controller will terminate the current cycle and completely release the soft startup capacitor. It is recommended to install a small RC filter near the controller to filter the current influenza response signal at the CS. At the beginning of each cycle, the internal MOSFET discharge 50ns of the external CS tube to reduce the cutting -edge MOSFET at the front of the cutting -edge peak when the opening of MOSFET is turned on. LM5041 current detection and PWM comparator are very fast, and may respond to short -term noise. The layout is essential for current detection filters and detection resistors. Related capacitors CS filters must be placed near the device and directly connected to the controller (CS and ground). If the current transformer is used, the two leads on the secondary side of the transformer shall be connected to the sensor resistor, and it shall also be located near IC. The resistance can be used in the current influenza transformer, which is located in the push -pull transistor source, but requires a low -induced resistor. When designing sensing resistors, all low -power grounding of noise should be connected around the IC, and it should be connected to large current power supply (inductive resistance locations) separately. The second-level current detection threshold is designed to protect the power converter by starting a low-occupation ratio. When the current is detected, the HICK-UP mode will appear. If the second -level threshold is reached, the soft start should be set to determine the soft startup electricityWhen a container, the capacitor will be discharged, and the starting order will begin to be completely released. Only when the high DV/DT appears in the current influenza pinnacle. The current detection transients must be fast enough to turn off the lower -voltage -level driver before reaching the second threshold. DV/DT, which is very high in current, may be short -circuited with saturated power induction or load. CS pins are filtered excessively, such as extremely low -value electric influenza resistance or electrical sensor, if the unsaturated overload may prevent the second level from reaching the threshold. If the second -level threshold is never exceeded under overload, the first -level current test will continue to be limited, and the output characteristics of the converter will the current of the current source. However, the continuous overload current will lead to the power transmission system, especially the output rectifier. The oscillator and synchronization function single resistor is connected by an external resistor LMD with GND 5041. The settings can be calculated based on the required oscillator frequency (RT):
The lower -voltage level will be switched at the frequency of the oscillator, and each push -pull output will be oscillating. Switch the frequency in the push -pushing configuration at half of the device. LM5041 can also be synchronized with the external clock. The frequency of the external clock must be higher than the free running frequency of the RT resistor. The clock signal should be coupled with a 100PF capacitor capacitor to the RT pin. The peak voltage level greater than 3V is required for synchronous pulse detection. Synchronous pulse width should be performed by external components. Regardless of whether the oscillator runs freely or external, the RT resistor is required to synchronize. The voltage at the RT pin is adjusted to 2V. The RT resistor should be located near the device and directly connected to the IC pin (RT and GND).
Slope compensation
PWM comparator compares the voltage signal signal with the voltage on the compensation pin. Output -level internal error Player usually drives a COMP pin. When the duty cycle is greater than 50%, the current control circuit is affected by secondary resonance oscillation. By adding an additional fixed slope signal (slope compensation) current, the current influenza should avoid oscillation. LM5041 integrates this slope to compensate the internal current with current with current slope by buffering an internal oscillator slope and seeking the current slope generated by the oscillator. You can provide additional slope compensation for the impedance of the fluidum signal by increasing the source.
Soft start and closure
Soft startup function allows power converters to gradually reach the initial steady -state working point, thereby reducing the boost pressure and surge. When power -on, the soft startup pins output 10UA current (SS) charge the external capacitor. The capacitor voltage will rise slowly and will limit the maximum duty cycle to the cycle of Barc. If the VCC owed pressure, the circuit voltage, or the faulty -electric current limit of the second indicator, the output drive is disabled, and the soft startup capacitor discharges the ground. When the fault conditions no longer exist, the soft startup program will start again, and the duty occupation ratio during the antihypertension phase will gradually increase as the soft startup capacitor is charged. SS pin can also be used as enable input. If the SS pin is compulsive than 0.45V threshold, the controller will enter a low power state.
Heat Protection
Provides internal heat shutdown circuits to maximize more than knot temperature.When activated, when the degree of 165 degrees Celsius, the controller enters the low -power standby state and close the output drive and partial pressure regulator.This function is provided to prevent catastrophic failures caused by overheating equipment.