SLUS577D November   2011  – August 2016 UCC2817A , UCC2818A , UCC3817A , UCC3818A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision
  5. 5 Description (Continued)
  6. 6 Device Comparison Tables
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Reference Section and Error Amplifier
      2. 9.3.2 Zero Power Block
      3. 9.3.3 Multiplier
      4. 9.3.4 Output Overvoltage Protection
      5. 9.3.5 Pin Descriptions
        1. 9.3.5.1  CAI
        2. 9.3.5.2  CAOUT
        3. 9.3.5.3  CT
        4. 9.3.5.4  DRVOUT
        5. 9.3.5.5  GND
        6. 9.3.5.6  IAC
        7. 9.3.5.7  MOUT
        8. 9.3.5.8  OVP/EN
        9. 9.3.5.9  PKLMT
        10. 9.3.5.10 RT
        11. 9.3.5.11 SS
        12. 9.3.5.12 VAOUT
        13. 9.3.5.13 VCC
        14. 9.3.5.14 VFF
        15. 9.3.5.15 VSENSE
        16. 9.3.5.16 VREF
    4. 9.4 Device Functional Modes
      1. 9.4.1 Transition Mode Control
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Power Stage
          1. 10.2.2.1.1 LBOOST
          2. 10.2.2.1.2 COUT
          3. 10.2.2.1.3 Power Switch Selection
        2. 10.2.2.2 Soft Start
        3. 10.2.2.3 Multiplier
        4. 10.2.2.4 Voltage Loop
        5. 10.2.2.5 Current Loop
        6. 10.2.2.6 Start-Up
        7. 10.2.2.7 Capacitor Ripple Reduction
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Bias Current
      2. 12.1.2 VREF
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Related Links
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Community Resource
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • PW|16
  • N|16
  • D|16
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8 Specifications

8.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Supply voltage VCC 18 V
Supply current ICC 20 mA
Gate drive current, continuous 0.2 A
Gate drive current 1.2 A
Input voltage, CAI, MOUT, SS 8 V
Input voltage, PKLMT 5 V
Input voltage, VSENSE, OVP/EN 10 V
Input current, RT, IAC, PKLMT 10 mA
Input current, VCC (no switching) 20 mA
Maximum negative voltage, DRVOUT, PKLMT, MOUT –0.5 V
Power dissipation 1 W
Lead temperature, Tsol (soldering, 10 seconds) 300 °C
Power dissipation 1 W
Junction temperature, TJ –55 150 °C
Storage temperature, Tstg –65 150 °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.

8.2 ESD Ratings

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-C101(2) ±1500
(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.

8.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN NOM MAX UNIT
VCC Input voltage 12 18 V
VSENSE Input sense voltage 7.5 10 V
Input current for oscillator 1.36 10 mA

8.4 Thermal Information

THERMAL METRIC(1) UCCx81xA UNIT
D (SOIC) N (PDIP) PW (TSSOP)
16 PINS 16 PINS 16 PINS
RθJA Junction-to-ambient thermal resistance 73.9 49.3 98.9 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 33.5 38.9 30.2 °C/W
RθJB Junction-to-board thermal resistance 31.4 29.4 44.8 °C/W
ψJT Junction-to-top characterization parameter 5.8 18.9 1.9 °C/W
ψJB Junction-to-board characterization parameter 31.1 29.2 44.1 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

8.5 Electrical Characteristics

TA = 0°C to 70°C for the UCC3817A and TA = –40°C to 85°C for the UCC2817A, TA = TJ, VCC = 12 V, RT = 22 kΩ, CT = 270 pF, (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY CURRENT SECTION
Supply current, OFF VCC = (VCC turnon threshold –0.3 V) 150 300 µA
Supply current, ON VCC = 12 V, No load on DRVOUT 2 4 6 mA
UVLO SECTION
VCC turnon threshold (UCCx817) 15.4 16 16.6 V
VCC turnoff threshold (UCCx817) 9.4 9.7 V
UVLO hysteresis (UCCx817) 5.8 6.3 V
Maximum shunt voltage (UCCx817) IVCC = 10 mA 15.4 17 17.5 V
VCC turnon threshold (UCCx818) 9.7 10.2 10.8 V
VCC turnoff threshold (UCCx818) 9.4 9.7 V
UVLO hysteresis (UCCx818) 0.3 0.5 V
VOLTAGE AMPLIFIER SECTION
Input voltage TA = 0°C to 70°C 7.387 7.5 7.613 V
TA = -–40°C to 85°C 7.369 7.5 7.631
VSENSE bias current VSENSE = VREF, VAOUT = 2.5 V 50 200 nA
Open-loop gain VAOUT = 2 V to 5 V 50 90 dB
High-level output voltage IL = –150 µA 5.3 5.5 5.6 V
Low-level output voltage IL = 150 µA 0 50 150 mV
OVER VOLTAGE PROTECTION AND ENABLE SECTION
Over voltage reference VREF +0.48 VREF +0.50 VREF +0.52 V
Hysteresis 300 500 600 mV
Enable threshold 1.7 1.9 2.1 V
Enable hysteresis 0.1 0. 0.3 V
CURRENT AMPLIFIER SECTION
Input offset voltage VCM = 0 V, VCAOUT = 3 V –3.5 0 2.5 mV
Input bias current VCM = 0 V, VCAOUT = 3 V –50 –100 nA
Input offset current VCM = 0 V, VCAOUT = 3 V 25 100 nA
Open loop gain VCM = 0 V, VCAOUT = 2 V to 5 V 90 dB
Common-mode output voltage VCM = 0 V to 1.5 V, VCAOUT = 3 V 60 80 dB
High-level output voltage IL = –120 mA 5.6 6.5 6.8 VV
Low-level output voltage IL = 1 mA 0.1 0.2 0.5 MHz
Gain bandwidth product See (1) 2.5
VOLTAGE REFERENCE SECTION
Input voltage TA = 0°C to 70°C 7.387 7.5 7.613 V
TA = -–40°C to 85°C 7.369 7.5 7.631
Load regulation IREF = 1 mA to 2 mA 0 10 mV
Line regulation VCC = 10.8 to 15 V(2) 0 10 mV
Short-circuit current VREF = 0 V –20 –25 –50 mA
OSCILLATOR SECTION
Initial accuracy TA = 25°C 85 100 115 kHz
Voltage stability VCC = 10.8 to 15 V –1% 1%
Total variation Line, temp 80 120 kHz
Ramp peak voltage 4.5 5 5.5 V
Ramp amplitude voltage (peak to peak) 3.5 4 4.5 V
PEAK CURRENT LIMIT SECTION
PKLMT reference voltage –15 15 mV
PKLMT propagation delay 150 350 500 ns
MULTIPLIER SECTION
IMOUT, high line, low power output current, (0°C to 85°C) IAC = 500 µA, VFF = 4.7 V, VAOUT = 1.25 V 0 –6 –20 µA
IMOUT, high line, low power output current, (–40°C to 85°C) IAC = 500 µA, VFF = 4.7 V, VAOUT = 1.25 V 0 –6 –23
IMOUT, high line, low power output current IAC = 500 µA, VFF = 4.7 V, VAOUT = 5 V –70 –90 –105
IMOUT, low line, low power output current IAC = 150 µA, VFF = 1.4 V, VAOUT = 1.25 V –10 –19 –50
IMOUT, low line, high power output current IAC = 150 µA, VFF = 1.4 V, VAOUT = 5 V –268 –300 –345
IMOUT, IAC limited output current IAC = 150 µA, VFF = 1.3 V, VAOUT = 5 V –250 –300 –400
Gain constant (K) IAC = 150 µA, VFF = 1.3 V, VAOUT = 2.5 V 0.5 1 1.5 1/V
IMOUT, zero current IAC = 150 µA, VFF = 1.4 V, VAOUT = 0.25 V 0 –2 µA
IAC = 500 µA, VFF = 4.7 V, VAOUT = 0.25 V 0 –2
IMOUT, zero current, (0°C to 85°C) IAC = 500 µA, VFF = 4.7 V, VAOUT = 0.5 V 0 –3 µA
IMOUT, zero current, (–40°C to 85°C) IAC = 500 µA, VFF = 4.7 V, VAOUT = 0.5 V 0 –3.5
Power limit (IMOUT x VFF) IAC = 150 µA, VFF = 1.4 V, VAOUT = 5 V –375 –420 –485 µW
FEED-FORWARD SECTION
VFF output current IAC = 300 µA –140 –150 –160 µA
SOFT START SECTION
SS charge current –6 –10 –16 µA
GATE DRIVER SECTION
Pullup resistance IO = –100 mA to –200 mA 9 12 Ω
Pulldown resistance IO = 100 mA 4 10
Output rise time CL = 1 nF, RL = 10 Ω, VDRVOUT = 0.7 V to 9 V 25 50 ns
Output fall time CL = 1 nF, RL = 10 Ω, VDRVOUT = 9 V to 0.7 V 10 50
Maximum duty cycle 93% 95% 99%
Minimum controlled duty cycle At 100 kHz 2%
ZERO POWER SECTION
Zero power comparator threshold Measured on VAOUT 0.2 0.33 0.5 V
(1) Ensured by design, not production tested.
(2) Reference variation for VCC < 10.8 V is shown in Figure 12.

8.6 Typical Characteristics

UCC2817A UCC2818A UCC3817A UCC3818A D001_sluu077.gif
Figure 1. Efficiency vs Output Power
UCC2817A UCC2818A UCC3817A UCC3818A D002_sluu077.gif
Figure 2. Power Factor vs Output Power