SNVS443C May   2006  – December 2016 LM3489 , LM3489-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: LM3489
    3. 6.3 ESD Ratings: LM3489-Q1
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 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 Hysteretic Control Circuit
        1. 7.3.1.1 Delay
      2. 7.3.2 Current Limit Operation
      3. 7.3.3 Start Up
      4. 7.3.4 External Sense Resistor
      5. 7.3.5 PGATE
      6. 7.3.6 Adjustable UVLO
    4. 7.4 Device Functional Mode
      1. 7.4.1 Device Enable and Shutdown
  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 Inductor Selection (L)
        2. 8.2.2.2 Output Capacitor Selection (COUT)
        3. 8.2.2.3 Input Capacitor Selection (CIN)
        4. 8.2.2.4 Programming the Current Limit (RADJ)
        5. 8.2.2.5 Catch Diode Selection (D1)
        6. 8.2.2.6 P-Channel MOSFET Selection (Q1)
        7. 8.2.2.7 Interfacing With the Enable Pin
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Related Links
    2. 11.2 Receiving Notification of Documentation Updates
    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

Package Options

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

6 Specifications

6.1 Absolute Maximum Ratings

See (1).
MIN MAX UNIT
VIN voltage –0.3 36 V
PGATE voltage –0.3 36 V
FB voltage –0.3 5 V
ISENSE voltage –1 36 V
–1 (<100 ns)
ADJ voltage –0.3 36 V
EN voltage(2) –0.3 6 V
Power dissipation, TA = 25°C(3) 417 mW
Junction temperature, TJ –40 150 °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.
(2) This pin is internally pulled high and clamped at 8 V (typical). The absolute maximum and operating maximum rating specifies the input level allowed for an external voltage source applied to this pin without triggering the internal clamp with margin.
(3) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ_MAX, the junction-to-ambient thermal resistance, RθJA and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated using: PD= (TJ – TA) / RθJA. Exceeding the maximum allowable power dissipation will lead to excessive die temperature.

6.2 ESD Ratings: LM3489

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) ±750
(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: LM3489-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

6.4 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN MAX UNIT
VIN Supply voltage 4.5 35 V
EN voltage(1) 5.5 V
TJ Operating junction temperature(2) LM3489 –40 125 °C
LM3489-Q1 –40 150 °C
(1) This pin is internally pulled high and clamped at 8 V (typical). The absolute maximum and operating maximum rating specifies the input level allowed for an external voltage source applied to this pin without triggering the internal clamp with margin.
(2) High junction temperatures degrade operating lifetimes. Operating lifetime is de-rated for junction temperatures greater than 125°C.

6.5 Thermal Information

THERMAL METRIC(1) LM3489 UNIT
DGK (VSSOP)
8 PINS
RθJA Junction-to-ambient thermal resistance 163.7 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 56.6 °C/W
RθJB Junction-to-board thermal resistance 83.3 °C/W
ψJT Junction-to-top characterization parameter 5.4 °C/W
ψJB Junction-to-board characterization parameter 82 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance — °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

6.6 Electrical Characteristics

Typical values correspond to TJ = 25°C. Minimum and maximum limits apply over TJ = –40°C to 125°C for the LM3489 and LM3489-Q1. VIN = 12 V, VISNS = VIN − 1 V, and VADJ = VIN − 1.1 V (unless otherwise noted).
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
ISHDN Shutdown input supply current EN = 0 V 7 15 µA
VEN Enable threshold voltage Enable rising 1.15 1.5 1.85 V
VEN_HYST Enable threshold hysteresis 130 mV
IQ Quiescent current at ground pin FB = 1.5 V (not switching) 280 400 µA
VFB Feedback voltage(1) 1.214 1.239 1.264 V
VHYST Comparator hysteresis 10 20 mV
VCL_OFFSET Current limit comparator offset VFB = 1 V –20 0 20 mV
ICL_ADJ Current limit ADJ current source VFB = 1.5 V 3 5.5 7 µA
TCL Current limit one-shot off-time VADJ = 11.5 V, VISNS = 11 V, VFB = 1 V 6 9 14 µs
RPGATE Driver resistance Source, ISOURCE = 100 mA 5.5 Ω
Sink, ISINK = 100 mA 8.5
IPGATE Driver output current Source, VIN = 7 V, PGATE = 3.5 V 0.44 A
Sink, VIN = 7 V, PGATE = 3.5 V 0.1
IFB FB pin bias current(2) VFB = 1 V 300 750 nA
TONMIN_NOR Minimum ON time in normal operation VISNS = VADJ + 0.1 V, Cload on OUT = 1000 pF(3) 100 ns
TONMIN_CL Minimum ON time in current limit VISNS = VADJ – 0.1 V, VFB = 1 V,
Cload on OUT = 1000 pF(3)		 200 ns
%VFB/ΔVIN Feedback voltage line regulation 4.5 V ≤ VIN ≤ 35 V 0.01% V
(1) The VFB is the trip voltage at the FB pin when PGATE switches from high to low.
(2) Bias current flows out from the FB pin.
(3) A 1000-pF capacitor is connected between VIN and PGATE.

6.7 Typical Characteristics

At TA = 25°C and applicable to both LM3489 and LM3489-Q1 at VIN = 12 V with configuration in Detailed Description (unless otherwise noted).
LM3489 LM3489-Q1 20186901.gif Figure 1. Quiescent Current vs Input Voltage
LM3489 LM3489-Q1 20186903.gif Figure 3. Feedback Voltage vs Temperature
LM3489 LM3489-Q1 20186905.gif Figure 5. Feedback Voltage Hysteresis vs Temperature
LM3489 LM3489-Q1 20186907.gif Figure 7. Current Limit One Shot OFF Time vs Temperature
LM3489 LM3489-Q1 20186941.gif Figure 9. Minimum ON Time
vs Temperature (Normal Operation)
LM3489 LM3489-Q1 20186911.gif Figure 11. Operating ON Time vs Load Current
LM3489 LM3489-Q1 20186915.gif
VOUT = 5 V, L = 22 µH
Figure 13. Efficiency vs Load Current
LM3489 LM3489-Q1 20186918.gif
VIN = 12 V, VOUT = 3.3 V, IOUT = 500 mA
Figure 15. Continuous Mode Operation
LM3489 LM3489-Q1 20186955.png
VOUT = 3.3 V, 500 mA loaded
Figure 17. Enable Transient
LM3489 LM3489-Q1 20186902.gif Figure 2. Shutdown Current vs Input Voltage
LM3489 LM3489-Q1 20186904.gif Figure 4. Feedback Voltage Hysteresis vs Input Voltage
LM3489 LM3489-Q1 20186906.gif Figure 6. Current Limit ADJ Current vs Temperature
LM3489 LM3489-Q1 20186940.gif Figure 8. VIN – VPGATE vs VIN
LM3489 LM3489-Q1 20186910.gif Figure 10. Minimum ON Time
vs Temperature (Current Limit)
LM3489 LM3489-Q1 20186952.gif Figure 12. Operating Frequency vs Input Voltage
LM3489 LM3489-Q1 20186916.gif
VOUT = 5 V, L = 22 µH
Figure 14. VOUT Regulation vs Load Current
LM3489 LM3489-Q1 20186951.gif
VIN = 12 V, VOUT =3.3 V, IOUT = 50 mA
Figure 16. Discontinuous Mode Operation
LM3489 LM3489-Q1 20186956.png
VOUT = 3.3 V, 500 mA loaded
Figure 18. Shutdown Transient