SLUS515G September   2002  – December 2015

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 UVLO and Reference Block
      2. 7.3.2 Error Amplifier
      3. 7.3.3 Zero Current Detection and Re-Start Timer Blocks
      4. 7.3.4 Enable Block
      5. 7.3.5 Zero Power Block
      6. 7.3.6 Multiplier Block
      7. 7.3.7 Overvoltage Protection (OVP) Block
    4. 7.4 Device Functional Modes
      1. 7.4.1 Transition Mode Control
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Inductor Selection
        2. 8.2.2.2 MOSFET Selection
        3. 8.2.2.3 Diode Selection
        4. 8.2.2.4 Capacitor Selection
        5. 8.2.2.5 Multiplier Set-Up
        6. 8.2.2.6 Sense Resistor Selection
        7. 8.2.2.7 Output Voltage Sense Design
        8. 8.2.2.8 Voltage Loop Design
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Bias Current
      2. 10.1.2 Zero Current Detection
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
    2. 11.2 Related Links
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Supply voltage, VCC (Internally clamped) 20 V
Input current into VCC clamp IDD 30 mA
Input current ZCD ±10 mA
Gate drive current (peak), IDRV DRV ±750 mA
Input voltage, VCC VO_SNS, MULTIN, CS 5 V
Maximum negative voltage VO_SNS, MULTIN, DRV, CS –0.5 V
Power dissipation at TA = 50°C D package 650 mW
P package 1 W
Operating junction temperature range, TJ –55 150 °C
Storage temperature, Tstg –65 150 °C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 300 °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.

6.2 ESD Ratings

VALUE UNIT
SOIC PACKAGE
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) ±500 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 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN NOM MAX UNIT
VCC input voltage from a low-impedance source VCCOFF + 1 V 18 V
Operating junction temperature, TJ –40 125 °C

6.4 Thermal Information

THERMAL METRIC(1) UCC2805x, UCC3805x UNIT
D (SOIC) P (PDIP)
8 PINS 8 PINS
RθJA Junction-to-ambient thermal resistance 113.6 55.6 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 60.3 45.5 °C/W
RθJB Junction-to-board thermal resistance 54.3 32.7 °C/W
ψJT Junction-to-top characterization parameter 14 23.1 °C/W
ψJB Junction-to-board characterization parameter 53.8 32.6 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics

TA = 0°C to 70°C for the UCC3805x, –40°C to +105°C for the UCC2805x, TA = TJ, VCC = 12 V.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY
VCC operating voltage 18 V
Shunt voltage IVCC = 25 mA 18 19 20 V
Supply current, off VCC = VCC turnon threshold –300 mV 75 125 µA
Supply current, disabled VO_SNS = 0.5 V 2 4 mA
Supply current, on 75 kHz, CL = 0 nF 4 6 mA
Supply current, dynamic operating 75 kHz, CL = 1 nF 5 7 mA
UVLO
VCC turnon threshold UCCx8050 15.4 15.8 16.4 V
UCCx8051 12 12.5 13
VCC turnoff threshold 9.4 9.7 10 V
UVLO hysteresis UCCx8050 5.8 6.3 6.8 V
UCCx8051 2.3 2.8 3.3
VOLTAGE AMPLIFIER (VO_SNS)
Input voltage (VREF) UCC3805x 2.46 2.5 2.54 V
UCC2805x 2.45 2.5 2.55
Input bias current 0.5 µA
VCOMP high VO_SNS = 2.1 V 4.5 5.5 V
VCOMP low VO_SNS = 2.55 V 1.8 2.45 V
gM TJ = 25 °C, VCOMP = 3.5 V 60 90 130 µS
Source current UCCx8050 VO_SNS = 2.1 V, VCOMP = 3.5 V –0.2 –0.1 mA
UCCx8051 VO_SNS = 2.1 V, VCOMP = 2.5 V –200 –300 –400 µA
Sink current VO_SNS = 2.7 V, VCOMP = 3.5 V 0.2 1 mA
OVER VOLTAGE PROTECTION / ENABLE
Overvoltage reference UCCx8050 VREF + 0.165 VREF + 0.19 VREF + 0.21 V
UCCx8051 VREF + 0.15 VREF + 0.18 VREF + 0.21
Hysteresis UCCx8050 175 200 225 mV
UCCx8051 150 180 210
Enable threshold UCCx8050 0.62 0.67 0.72 V
UCCx8051 0.18 0.23 0.28
Enable hysteresis 0.05 0.1 0.2 V
MULTIPLIER
Multiplier gain constant (k) VMULTIN = 0.5 V, COMP = 3.5 V 0.43 0.65 0.87 1/V
Dynamic input range, VMULTIN INPUT 0 to 2.5 0 to 3.5 V
Dynamic input range, COMP INPUT 2.5 to 3.8 2.5 to 4 V
Input bias current, MULTIN 0.1 1 µA
ZERO POWER
Zero power comparator threshold(1) Measured on VCOMP 2.1 2.3 2.5 V
ZERO CURRENT DETECT
Input threshold (rising edge)(1) 1.5 1.7 2 V
Hysteresis(1) 250 350 450 mV
Input high clamp I = 3 mA 5 6 V
Input low clamp I = −3 mA 0.3 0.65 0.9 V
Restart time delay 200 400 µs
CURRENT SENSE COMPARATOR
Input bias current CS = 0 V 0.1 1 µA
Input offset voltage(1) –10 10 mV
Delay to output CS to DRV 300 450 ns
Maximum current sense threshold voltage 1.55 1.7 1.8 V
PFC GATE DRIVER
GT1 pull-up resistance IOUT = –125 mA 5 12 Ω
GT1 pull-down resistance IOUT = 125 mA 2 10 Ω
GT1 output rise time CLOAD = 1 nF, RLOAD = 10 Ω 25 75 ns
GT1 output fall time CLOAD = 1 nF, RLOAD = 10 Ω 10 50 ns
(1) Ensured by design. Not production tested.

6.6 Typical Characteristics

UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_1.gif
Figure 1. Supply Current vs Supply Voltage
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_3.gif
Figure 3. UVLO Thresholds vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_5.gif
Figure 5. Current Sense Input Threshold vs Multiplier Input Voltage
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_7.gif
Figure 7. CS To Output Delay Time vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_9.gif
Figure 9. gM Amplifier Output Current vs Output Sense Voltage
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_11.gif
Figure 11. Voltage Amplifier Output vs Time (UCC38050)
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_13.gif
Figure 13. Zero Current Detection Clamp Current vs Voltage
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_15.gif
Figure 15. Output Saturation Voltage vs Source Current
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_2.gif
Figure 2. Supply Current vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_4.gif
Figure 4. Reference Voltage vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_6.gif
Figure 6. Maximum Current Sense Threshold vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_8.gif
Figure 8. Transconductance vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_10.gif
Figure 10. gM Amplifier Output Current vs Output Sense Voltage (Small Signal View)
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_12.gif
Figure 12. Overvoltage Protection Thresholds vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_14.gif
Figure 14. Restart Time vs Temperature
UCC28050 UCC28051 UCC38050 UCC38051 slus515_typchar_16.gif
Figure 16. Output Saturation Voltage vs Sink Current