SLUS646K November   2005  – August 2015 UCC28600

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
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
      1. 7.2.1 Terminal Components
    3. 7.3 Feature Description
      1. 7.3.1 Oscillator
      2. 7.3.2 Status
      3. 7.3.3 Fault Logic
      4. 7.3.4 Protection Features
      5. 7.3.5 Overtemperature
      6. 7.3.6 Cycle-by-Cycle Power Limit
      7. 7.3.7 Primary Current Protection
      8. 7.3.8 Over-Voltage Protection
      9. 7.3.9 Undervoltage Lockout
    4. 7.4 Device Functional Modes
      1. 7.4.1 Quasi-Resonant and DCM Control
      2. 7.4.2 Frequency Foldback Mode Control
      3. 7.4.3 Green-Mode Control
      4. 7.4.4 Operating Mode Programming
  8. 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 Input Bulk Capacitor and Minimum Bulk Voltage
        2. 8.2.2.2 Transformer Turns Ratio and Primary Inductance
        3. 8.2.2.3 Non-Ideal Current Sense Value
        4. 8.2.2.4 Snubber Damping
        5. 8.2.2.5 Open Loop Test Circuit
      3. 8.2.3 Application Curves
    3. 8.3 Do's and Don'ts
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
      2. 11.2.2 Related Products
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|8
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
VDD Supply voltage range, IDD < 20 mA 32 V
IDD Supply current 20 mA
IOUT(sink) Output sink current (peak) 1.2 A
IOUT(source) Output source current (peak) –0.8 A
Analog inputs: FB, CS, SS –0.3 6.0 V
VOVP –1.0 6.0 V
IOVP(source) –1.0 mA
VSTATUS VDD = 0 V to 30 V 30 V
Power dissipation, SOIC-8 package, TA = 25°C 650 mW
TLEAD Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 300 °C
TJ Operating junction temperature –55 150 °C
Tstg Storage temperature –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.

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins (1) ±2000 V
Charged device model (CDM), per JEDEC specification JESD22-C101, all pins (2) ±1500 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
VDD Input voltage 21 V
CVDD VDD bypass capacitor 0.1 1.0 μF
CFB FB filter capacitor 390 pF
TJ Operating junction temperature –40 105 °C

6.4 Thermal Information

THERMAL METRIC (1) UCC28600 UNIT
D (SOIC)
8 PINS
RθJA Junction-to-ambient thermal resistance 108.9 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 55.5 °C/W
RθJB Junction-to-board thermal resistance 48.9 °C/W
ψJT Junction-to-top characterization parameter 10.5 °C/W
ψJB Junction-to-board characterization parameter 48.5 °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

VDD = 15 V, 0.1-μF capacitor from VDD to GND, 3.3-nF capacitor from SS to GND charged over 3.5 V, 500-Ω resistor from OVP to –0.1 V, FB = 4.8 V, STATUS = not connected, 1-nF capacitor from OUT to GND, CS = GND, TA = –40°C to +105°C, (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
ISTARTUP Start-up current VDD = VUVLO –0.3 V 12 25 μA
ISTANDBY Standby current VFB = 0 V 350 550 μA
IDD Operating current Not switching 2.5 3.5 mA
130 kHz, QR mode 5.0 7.0 mA
VDD clamp FB = GND, IDD = 10 mA 21 26 32 V
UNDERVOLTAGE LOCKOUT
VDD(uvlo) Start-up threshold VDD increasing 10.3 13.0 15.3 V
VDD(uvlo) Stop threshold VDD decreasing 6.3 8 9.3 V
ΔVDD(uvlo) Hysteresis 4.0 5.0 6.0 V
PWM (RAMP) (2)
DMIN Minimum duty cycle VSS = GND, VFB = 2 V 0%
DMAX Maximum duty cycle QR mode, fS = max, (open loop) 99%
OSCILLATOR (OSC)
fQR(max) Maximum QR and DCM frequency 117 130 143 kHz
fQR(min) Minimum QR and FFM frequency VFB = 1.3 V 32 40 48 kHz
fSS Soft start frequency VSS = 2.0 V 32 40 48 kHz
dTS/dFB VCO gain TS for 1.6 V < VFB < 1.8 V –38 –30 –22 μs/V
FEEDBACK (FB)
RFB Feedback pullup resistor 12 20 28 kΩ
VFB FB, no load QR mode 3.30 4.87 6.00 V
Green-mode ON threshold VFB threshold 0.3 0.5 0.7 V
Green-mode OFF threshold VFB threshold 1.2 1.4 1.6 V
Green-mode hysteresis VFB threshold 0.7 0.9 1.1 V
FB threshold burst-ON VFB during green mode 0.3 0.5 0.7 V
FB threshold burst-OFF VFB during green mode 0.5 0.7 0.9 V
Burst Hysteresis VFB during green mode 0.13 0.25 0.42 V
STATUS
RDS(on) STATUS on resistance VSTATUS = 1 V 1.0 2.4 3.8 kΩ
ISTATUS(leakage) STATUS leakage/off current VFB = 0.44 V, VSTATUS = 15 V –0.1 2.0 μA
CURRENT SENSE (CS) (2)
ACS(FB) Gain = ΔVFB / ΔVCS QR mode 2.5 V/V
Shutdown threshold VFB = 2.4 V, VSS = 0 V 1.13 1.25 1.38 V
CS discharge impedance CS = 0.1 V, VSS = 0 V 25 115 250 Ω
VCS(os) CS offset SS mode, VSS ≤ 2.0 V 0.35 0.40 0.45 V
POWER LIMIT (PL) (2)
IPL(cs) CS current OVP = –300 μA –165 –150 –135 μA
Peak CS voltage QR mode 0.70 0.81 0.92 V
VPL PL threshold Peak CS voltage + CS offset 1.05 1.20 1.37 V
SOFT START (SS)
ISS(chg) Softstart charge current VSS = GND –8.3 –6.0 –4.5 μA
ISS(dis) Softstart discharge current VSS = 0.5 V 2.0 5.0 10 mA
VSS Switching ON threshold Output switching start 0.8 1.0 1.2 V
OVERVOLTAGE PROTECTION (OVP)
IOVP(line) Line overvoltage protection IOVP threshold, OUT = HI –512 –450 –370 μA
VOVP(on) OVP voltage at OUT = HIGH VFB = 4.8 V, VSS = 5.0 V,
IOVP(on), = –300 μA		 –125 –25 mV
VOVP(load) Load overvoltage protection VOVP threshold, OUT = LO 3.37 3.75 4.13 V
THERMAL PROTECTION (TSP)
Thermal shutdown (TSP) temperature (1) 130 140 150 °C
Thermal shutdown hysteresis 15 °C
(1) Ensured by design. Not production tested.
(2) RCST and CCST are not connected in the circuit for maximum and minimum duty cycle tests, current sense tests, and power limit tests.

Timing Requirements

MIN NOM MAX UNIT
CURRENT SENSE (CS) (2)
CS to output delay time (power limit), CS = 1.0 VPULSE 100 175 300 ns
CS to output delay time (over current fault), CS = 1.45 VPULSE 50 100 150 ns
OUT
tRISE Rise time, 10% to 90% of 13-V typical OUT clamp 50 75 ns
tFALL Fall time 10 20 ns

6.6 Typical Characteristics

UCC28600 lus646_wave12.gif
Figure 1. Clamp Voltage vs. Temperature
UCC28600 lus646_wave14.gif
Figure 3. PL Threshold vs. Temperature
UCC28600 lus646_wave13.gif
Figure 2. Switching Frequency vs. Temperature
UCC28600 fig4k_lus646.gif
Figure 4. Over-Voltage Protection Threshold vs. Temperature