SNVS714F April   2011  – August 2015 LM25117 , LM25117-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings (LM25117)
    3. 6.3 ESD Ratings (LM25117-Q1)
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  High Voltage Startup Regulator and VCC Disable
      2. 7.3.2  UVLO
      3. 7.3.3  Oscillator And Sync Capability
      4. 7.3.4  Ramp Generator and Emulated Current Sense
      5. 7.3.5  Error Amplifier and PWM Comparator
      6. 7.3.6  Soft-Start
      7. 7.3.7  Cycle-By-Cycle Current Limit
      8. 7.3.8  Hiccup Mode Current Limiting
      9. 7.3.9  HO and LO Drivers
      10. 7.3.10 Current Monitor
      11. 7.3.11 Maximum Duty Cycle
      12. 7.3.12 Thermal Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Diode Emulation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
    3. 8.3 Detailed Design Procedure
      1. 8.3.1  Feedback Compensation
      2. 8.3.2  Sub-Harmonic Oscillation
      3. 8.3.3  Design Requirements
      4. 8.3.4  Timing Resistor RT
      5. 8.3.5  Output Inductor LO
      6. 8.3.6  Diode Emulation Function
      7. 8.3.7  Current Sense Resistor RS
      8. 8.3.8  Current Sense Filter RCS and CCS
      9. 8.3.9  Ramp Resistor RRAMP and Ramp Capacitor CRAMP
      10. 8.3.10 UVLO Divider RUV2, RUV1 and CFT
      11. 8.3.11 VCC Disable and External VCC Supply
      12. 8.3.12 Power Switches QH and QL
      13. 8.3.13 Snubber Components RSNB and CSNB
      14. 8.3.14 Bootstrap Capacitor CHB and Bootstrap Diode DHB
      15. 8.3.15 VCC Capacitor CVCC
      16. 8.3.16 Output Capacitor CO
      17. 8.3.17 Input Capacitor CIN
      18. 8.3.18 VIN Filter RVIN, CVIN
      19. 8.3.19 Soft-Start Capacitor CSS
      20. 8.3.20 Restart Capacitor CRES
      21. 8.3.21 Output Voltage Divider RFB2 and RFB1
      22. 8.3.22 Loop Compensation Components CCOMP, RCOMP and CHF
    4. 8.4 Application Curves
      1. 8.4.1 Constant Current Regulator
      2. 8.4.2 Constant Voltage and Constant Current Regulator
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guideline
      1. 10.1.1 PC Board Layout Recommendations
  11. 11Device and Documentation Support
    1. 11.1 Community Resources
    2. 11.2 Related Links
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
VIN to AGND -0.3 45 V
SW to AGND -3.0 45 V
HB to SW -0.3 15 V
VCC to AGND(2) -0.3 15 V
HO to SW -0.3 HB+0.3 V
LO to AGND -0.3 VCC+0.3 V
FB, DEMB, RES, VCCDIS, UVLO to AGND -0.3 15 V
CM, COMP to AGND(3) -0.3 7 V
SS, RAMP, RT to AGND -0.3 7 V
CS, CSG, PGND, to AGND -0.3 0.3 V
Storage temperature, Tstg -55 150 °C
Junction Temperature -40 150 °C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) See Application and Implementation when input supply voltage is less than the VCC voltage.
(3) These pins are output pins. As such they are not specified to have an external voltage applied.

6.2 ESD Ratings (LM25117)

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000 V
Charged-device model (CDM), per JEDEC specification JESD22- V C101(2) ±750 V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

6.3 ESD Ratings (LM25117-Q1)

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per AEC Q100-002(1) ±2000 V
Charged-device model (CDM), per AEC Q100-011 ±750 V
(1) AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.

6.4 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted) (1)
MIN MAX UNIT
VIN(2) 4.5 42 V
VCC 4.5 14 V
HB to SW 4.5 14 V
Junction Temperature -40 125 °C
(1) Recommended Operating Conditions are conditions under which operation of the device is intended to be functional, but does not ensure specific performance limits. For specifications and test conditions see .Electrical Characteristics
(2) Minimum VIN operating voltage is defined with VCC supplied by the internal HV startup regulator and no external load on VCC. When VCC is supplied by an external source, minimum VIN operating voltage is 4.5 V.

6.5 Thermal Information

THERMAL METRIC(1) LM25117, LM25117-Q1 UNIT
PWP (HTSSOP) RTW (WQFN)
20 PINS 24 PINS
RθJA Junction-to-ambient thermal resistance 40 40 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 4 6 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.6 Electrical Characteristics

Typical limits are for TJ = 25°C only; typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Minimum and maximum limits apply over the junction temperature range of –40°C to +125°C. Unless otherwise specified, the following conditions apply: VVIN = 24 V, VVCCDIS = 0 V, RT = 25 kΩ, no load on LO & HO.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VIN SUPPLY
IBIAS VIN Operating Current (1) VSS = 0V 4.8 6.2 mA
VSS = 0V, VVCCDIS = 2V 0.4 0.55 mA
ISHUTDOWN VIN Shutdown Current VSS = 0V, VUVLO = 0V 16 40 µA
VCC Regulator
VCC(REG) VCC Regulation No Load 6.85 7.6 8.2 V
VCC Dropout (VIN to VCC) VVIN = 4.5V, No external load 0.05 0.14 V
VVIN = 5.0V, ICC = 20mA 0.4 0.5 V
VCC Sourcing Current Limit VVCC = 0V 30 42 mA
IVCC VCC Operating Current (1) VSS = 0V, VVCCDIS = 2V 4.0 5.0 mA
VSS = 0V, VVCCDIS = 2V, VVCC = 14V 5.8 7.3 mA
VCC Under-voltage Threshold VCC Rising 3.75 4.0 4.15 V
VCC Under-voltage Hysteresis 0.2 V
VCC Disable
VCCDIS Threshold VCCDIS Rising 1.22 1.25 1.29 V
VCCDIS Hysteresis 0.06 V
VCCDIS Input Current VVCCDIS = 0V -20 nA
VCCDIS Pull-down Resistance 500 kΩ
UVLO
UVLO Threshold UVLO Rising 1.22 1.25 1.29 V
UVLO Hysteresis Current VUVLO = 1.4V 15 20 25 µA
UVLO Shutdown Threshold UVLO Falling 0.23 0.3 V
UVLO Shutdown Hysteresis 0.1 V
Soft Start
ISS SS Current Source VSS = 0V 7 10 12 µA
SS Pull-down Resistance 13 24 Ω
Error Amplifier
VREF FB Reference Voltage Measured at FB, FB = COMP 788 800 812 mV
FB Input Bias Current VFB = 0.8V 1 nA
VOH COMP Output High Voltage ISOURCE = 3mA 2.8 V
VOL COMP Output Low Voltage ISINK = 3mA 0.26 V
AOL DC Gain 80 dB
fBW Unity Gain Bandwidth 3 MHz
PWM Comparator
tHO(OFF) Forced HO Off-time 260 320 440 ns
tON(MIN) Minimum HO On-time VVIN = 42V 100 ns
COMP to PWM comparator offset 1.2 V
Oscillator
fSW1 Frequency 1 RT = 25kΩ 180 200 220 kHz
fSW2 Frequency 2 RT = 10kΩ 430 480 530 kHz
RT Output Voltage 1.25 V
RT Sync Positive Threshold 2.6 3.2 3.95 V
Sync Pulse Width 100 ns
Current Limit
VCS(TH) Cycle-by-cycle Sense Voltage Threshold VRAMP = 0, CSG to CS 106 120 135 mV
CS Input Bias Current VCS = 0V -100 -66 µA
CSG Input Bias Current VCSG = 0V -100 -66 µA
Current Sense Amplifier Gain 10 V/V
Hiccup Mode Fault Timer 256 Cycles
RES
IRES RES Current Source 10 µA
VRES RES Threshold RES Rising 1.22 1.25 1.285 V
Diode Emulation
VIL DEMB Input Low Threshold 2.0 1.65 V
VIH DEMB Input High Threshold 2.95 2.5 V
SW Zero Cross Threshold -5 mV
DEMB Input Pull-down Resistance 50 kΩ
Current Monitor
Current Monitor Amplifier Gain CS to CM 17.5 20.5 23.5 V/V
Current Monitor Amplifier Gain Drift over Temperature -2 0 +2 %
Zero Input Offset 25 120 mV
HO Gate Driver
VOHH HO High-state Voltage Drop IHO = –100mA, VOHH = VHB - VHO 0.17 0.3 V
VOLH HO Low-state Voltage Drop IHO = 100mA, VOLH = VHO - VSW 0.1 0.2 V
HO Rise Time C-load = 1000pF (2) 6 ns
HO Fall Time C-load = 1000pF (2) 5 ns
IOHH Peak HO Source Current VHO = 0V, SW = 0V, HB = 7.6V 2.2 A
IOLH Peak HO Sink Current VHO = VHB = 7.6V 3.3 A
HB to SW Under-voltage 2.56 2.9 3.32 V
HB DC Bias Current HB - SW = 7.6V 65 100 µA
LO Gate Driver
VOHL LO High-state Voltage Drop ILO = –100mA, VOHL = VCC-VLO 0.17 0.27 V
VOLL LO Low-state Voltage Drop ILO = 100mA, VOLL = VLO 0.1 0.2 V
LO Rise Time C-load = 1000pF (2) 6 ns
LO Fall Time C-load = 1000pF (2) 5 ns
IOHL Peak LO Source Current VLO = 0V 2.5 A
IOLL Peak LO Sink Current VLO = 7.6V 3.3 A
Thermal
TSD Thermal Shutdown Temperature Rising 165 °C
Thermal Shutdown Hysteresis 25 °C
(1) Operating current does not include the current into the RT resistor.
(2) High and low reference are 80% and 20% of the pulse amplitude respectively.

6.7 Switching Characteristics

over operating free-air temperature range (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
TDLH LO fall to HO rise delay No load 72 ns
TDHL HO fall to LO rise delay 71 ns

6.8 Typical Characteristics

LM25117 LM25117-Q1 30155003.png
Figure 1. HO Peak Driver Current Vsoutput Voltage
LM25117 LM25117-Q1 30155005.png
Figure 3. Driver Dead Time vs VVCC
LM25117 LM25117-Q1 30155007.png
Figure 5. Forced Ho Off-Time vs Temperature
LM25117 LM25117-Q1 30155009.png
Figure 7. VVCC vs IVCC
LM25117 LM25117-Q1 30155070.png
Figure 9. VCS(TH) vs Temperature
LM25117 LM25117-Q1 30155073.png
Figure 11. VVCC vs Temperature
LM25117 LM25117-Q1 30155072.png
Figure 13. VCM vs IOUT
LM25117 LM25117-Q1 30155004.png
Figure 2. LO Peak Driver Current vs Output Voltage
LM25117 LM25117-Q1 30155006.png
Figure 4. Driver Dead Time vs Temperature
LM25117 LM25117-Q1 30155008.png
Figure 6. Switching Frequency vs RT
LM25117 LM25117-Q1 30155069.png
Figure 8. VVCC vs VVIN
LM25117 LM25117-Q1 30155071.png
Figure 10. VREF vs Temperature
LM25117 LM25117-Q1 301550162.png
Figure 12. Error Amp Gain And Phase vs Frequency
LM25117 LM25117-Q1 30155078.png
Figure 14. VCM vs VCSG-CS