LM5116MH National Semiconductor, LM5116MH Datasheet

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... The device is available in a power enhanced TSSOP-20 package featuring an exposed die attach pad to aid thermal dissipation. Typical Application © 2007 National Semiconductor Corporation Features ■ Emulated peak current mode ■ ...

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... Connection Diagram Ordering Information Ordering Number Package Type LM5116MH TSSOP-20EP LM5116MHX TSSOP-20EP Pin Descriptions Pin Name Description 1 VIN Chip supply voltage, input voltage monitor and input to the VCC regulator. 2 UVLO If the UVLO pin is below 1.215V, the regulator will be in standby mode (VCC regulator running, switching regulator disabled). If the UVLO pin voltage is above 1.215V, the regulator is operational. An external voltage divider can be used to set an under-voltage shutdown threshold. There is a fixed 5µ ...

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Pin Name Description 12 CS Current sense amplifier input. Connect to the top of the current sense resistor or the drain of the low-sided MOSFET if R current sensing is used. DS(ON) 13 CSG Current sense amplifier input. Connect to ...

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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND VCC, VCCX, UVLO to GND (Note 3) SW GND VOUT to GND CSG to GND LO to GND SS to GND FB to GND DEMB to GND Electrical Characteristics junction temperature range of -40° ...

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Symbol Parameter Soft Start SS Current Source SS Diode Emulation Ramp Disable Threshold Offset SS Output Low Voltage Error Amplifier V FB Reference Voltage REF FB Input Bias Current COMP Sink/Source Current A DC Gain OL f ...

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Symbol Parameter HO Gate Driver V HO Low-state Output Voltage OLH V HO High-state Output Voltage OHH HO Rise Time HO High-side Fall Time I Peak HO Source Current OHH I Peak HO Sink Current OLH under-voltage ...

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Typical Performance Characteristics Typical Application Circuit Efficiency Driver Dead-time vs Temperature Driver Sink Current vs VCC Driver Source Current vs VCC 30007503 HO High R 30007505 HO Low R 30007507 7 30007504 vs VCC DS(ON) 30007506 vs VCC DS(ON) 30007508 ...

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LO High R DS(ON) LO Low R DS(ON) Forced HO Off-time vs Temperature VCCX = 5V www.national.com vs VCC 30007509 vs VCC 30007511 30007513 8 EN Input Threshold vs Temperature 30007510 UVLO vs Temperature 30007512 HB DC ...

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Frequency 30007515 Frequency vs Temperature 30007517 Frequency vs Temperature 30007519 Error Amp Gain vs Frequency Error Amp Phase vs Frequency Current Limit Threshold vs. Temperature 9 30007516 30007518 30007520 www.national.com ...

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VIN Operating Current vs Temperature VCC UVLO vs Temperature VCC vs ICC www.national.com VCC vs Temperature 30007521 30007523 VCCX Switch R 30007525 10 30007522 VCC vs VIN 30007524 vs VCCX DS(ON) 30007526 ...

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Block Diagram and Typical Application Circuit 11 www.national.com ...

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Detailed Operating Description The LM5116 high voltage switching regulator features all of the functions necessary to implement an efficient high voltage buck regulator using a minimum of external components. This easy to use regulator integrates high-side and low-side MOS- FET ...

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UVLO An under-voltage lockout pin is provided to disable the regu- lator without entering the sleep mode. If the UVLO pin is pulled below 1.215V, the regulator enters a standby mode of oper- ation with the soft-start capacitor discharged and ...

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The sample-and-hold DC level is derived from a measure- ment of the recirculating current through either the low-side MOSFET or current sense resistor. The voltage level across the MOSFET or sense resistor is sampled and held just prior to the ...

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Using a current sense resistor in the source of the low-side MOSFET provides superior current limit accuracy compared to R sensing. R sensing is far less accurate due DS(ON) DS(ON) to the large variation of MOSFET R DS(ON) and part-to-part ...

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When a fault is detected (VCC under-voltage, UVLO pin < 1.215 0V) the soft-start capacitor is discharged. Once the fault condition is no longer present, a new soft-start sequence begins. HO ...

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For a 5V output, the maximum current sense signal occurs at the minimum input voltage calculated from: S For this example VCCX = 0V CS(TH) sense resistor is calculated as: The next lowest standard value ...

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These current peaks can be several amperes. The recom- mended value of C should be no smaller than 0.47µF, and VCC should be a good quality, low ESR, ceramic capacitor located at the pins of the IC to minimize potentially ...

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Where t and t are the rise and fall times of the MOSFET Switching loss is calculated for the high-side MOSFET only. Switching ...

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FIGURE 12. Overall Voltage Loop Gain and Phase If a network analyzer is available, the modulator gain can be measured and the error amplifier gain can be configured for the desired loop transfer function network analyzer is not ...

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FIGURE 13 VCC for V RAMP For V < 7.5V, a negative VCC is required. This can be OUT made with a simple charge pump from the LO gate output. Install a resistor from the RAMP pin ...

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www.national.com 22 ...

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... CRCW06031211F R5 R6, R7 CRCW06030R0J R8 CRCW0603103J R9 CRCW06031242F R10 CRCW0603183J R11 LRC-LRF2010-01- R010-F R12 R13 CRCW0603105J R14 U1 LM5116MHX Type Size Capacitor, Ceramic 0805 Capacitor, Ceramic 0603 Capacitor, Ceramic 0603 Capacitor, Ceramic 0603 Capacitor, Ceramic 0603 Capacitor, Ceramic 0603 Capacitor, Ceramic 1812 Capacitor, Ceramic 1210 ...

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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted TSSOP-20EP Outline Drawing NS Package Number MXA20A 24 ...

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Notes 25 www.national.com ...

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