SNVSAF7B August   2016  – February 2017 LM27762

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
    3. 7.3 Feature Description
      1. 7.3.1 Undervoltage Lockout
      2. 7.3.2 Input Current Limit
      3. 7.3.3 PFM Operation
      4. 7.3.4 Output Discharge
      5. 7.3.5 Power Good Output (PGOOD)
      6. 7.3.6 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Enable Mode
  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 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Positive Low-Dropout Linear Regulator and OUT+ Voltage Setting
        3. 8.2.2.3 Charge-Pump Voltage Inverter
        4. 8.2.2.4 Negative Low-Dropout Linear Regulator and OUT- Voltage Setting
        5. 8.2.2.5 External Capacitor Selection
          1. 8.2.2.5.1 Charge-Pump Output Capacitor
          2. 8.2.2.5.2 Input Capacitor
          3. 8.2.2.5.3 Flying Capacitor
          4. 8.2.2.5.4 LDO Output Capacitor
        6. 8.2.2.6 Power Dissipation
      3. 8.2.3 Application Curves
  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
        1. 11.1.1.1 Custom Design With WEBENCH® Tools
    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

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)(2)
MIN MAX UNIT
VIN to GND or GND to VOUT 5.8 V
EN+, EN- GND − 0.3 VIN V
CPOUT, OUT+ and OUT- , continuous output current 300 mA
OUT+, OUT- short-circuit duration to GND(3) 1 s
Continuous power dissipation(4) Internally limited
TJMAX(4) 150 °C
Operating input voltage, VIN 2.7 5.5 V
Operating output current, IOUT 0 250 mA
Operating ambient temperature, TA –40 85 °C
Operating junction temperature, TJ –40 125 °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) If Military/Aerospace specified devices are required, contact the TI Sales Office/Distributors for availability and specifications.
(3) OUT may be shorted to GND for one second without damage. However, shorting OUT to VIN may damage the device and must be avoided. Also, for temperatures above TA = 85°C, VOUT must not be shorted to GND or VIN or device may be damaged.
(4) Internal thermal shutdown circuitry protects the device from damage.

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±1000 V
Charged-device model (CDM), per JEDEC specification JESD22-C101(2) ±250
(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 MAX UNIT
Operating ambient temperature, TA –40 85 °C
Operating junction temperature, TJ –40 125 °C

6.4 Thermal Information

THERMAL METRIC(1) LM27762 UNIT
DSS (WSON)
12 PINS
RθJA Junction-to-ambient thermal resistance 62.2 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 54.7 °C/W
RθJB Junction-to-board thermal resistance 25.6 °C/W
ψJT Junction-to-top characterization parameter 1.8 °C/W
ψJB Junction-to-board characterization parameter 25.6 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance 9.2 °C/W
(1) For more information about traditional and new thermal metrics, see Semiconductor and IC Package Thermal Metrics.

6.5 Electrical Characteristics

Typical limits apply for TA = 25°C; minimum and maximum limits apply over the full temperature range. Unless otherwise specified VIN = 5 V, CIN = COUT+ = COUT– = 2.2 μF, C1 = 1 μF, CPOUT = 4.7 μF.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
IQ Supply current Open circuit, no load, EN+, EN– connected to VIN. (1) 390 µA
ISD Shutdown supply current 0.5 5 µA
ƒSW Switching frequency VIN = 3.6 V 1.7 2 2.3 MHz
RNEG Output resistance to CPOUT VIN = 5.5 V, IL = 100 mA 2.5 Ω
VLDO– LDO dropout voltage IL = 100 mA, VOUT– = −5 V 30 mV
PSRR Power supply rejection ratio, OUT– IL = 100 mA, VOUT– = −1.8 V, 10 kHz 50 dB
VN– Output noise voltage IL = 80 mA, 10 Hz to 100 kHz 22 µVRMS
VFB– Feedback pin reference voltage –1.238 –1.22 –1.202 V
VOUT– Adjustable output voltage 5.5 V ≥ VIN ≥ 2.7 V –5 –1.5 V
Load regulation 0 to 250 mA, VOUT = –1.8 V 34 µV/mA
Line regulation 5 V ≥ VIN ≥ 2.7 V, IL = 50 mA 1.5 mV/V
VLDO+ LDO dropout voltage IL = 100 mA, VOUT = 5 V 45 mV
PSRR Power supply rejection ratio, OUT+ IL = 100 mA, VOUT+ = 1.8 V, 10 kHz 43 dB
VN+ Output noise voltage IL = 80 mA, 10 Hz to 100 kHz 22 µVRMS
VFB+ Feedback pin reference voltage 1.182 1.2 1.218 V
VOUT+ Adjustable output voltage 5.5 V ≥ VIN ≥ 2.7 V 1.5 5 V
Load regulation 0 to 250 mA, VOUT = 1.8 V 11 µV/mA
Line regulation 5 V ≥ VIN ≥ 2.7 V, IL = 50 mA 1.9 mV/V
VIH Enable pin input voltage high 5.5 V ≥ VIN ≥ 2.7 V 1.2 V
VIL Enable pin input voltage low 5.5 V ≥ VIN ≥ 2.7 V 0.4 V
(1) When VIN = 5.5V charge pump may enter PWM mode in hot conditions.

6.6 Typical Characteristics

LM27762 D014_SNVSAF7.gif
VIN = 3.7 V VOUT = ±3 V
Figure 1. Output Voltage Ripple vs Output Current
LM27762 D015_SNVSAF7.gif
VOUT = ± 3.3 V
Figure 3. LDO Dropout Voltage vs Output Current
LM27762 D017_SNVSAF7.gif
VOUT = –3.3 V
Figure 5. Line Regulation for OUT-
LM27762 D019_SNVSAF7.gif
VIN = 4.3 V VOUT = –3.3 V
Figure 7. Load Regulation for OUT-
LM27762 D021_SNVSAF7.gif
VIN = 5.5 V
Figure 9. Efficiency for OUT–
LM27762 waveform_01_vposneg_shutdown_snvsaf7.png
Figure 11. Shutdown
LM27762 D022_SNVSAF7.gif
VOUT = ±3 V IOUT = ±100 mA
Figure 2. Output Voltage Ripple vs Input Voltage
LM27762 D016_SNVSAF7.gif
VIN = 5.5 V
Figure 4. Charge Pump Output Resistance vs Output Current
LM27762 D018_SNVSAF7.gif
VOUT = 3.3 V
Figure 6. Line Regulation for OUT+
LM27762 D020_SNVSAF7.gif
VIN = 4.3 V VOUT = 3.3 V
Figure 8. Load Regulation for OUT+
LM27762 waveform_02_vposneg_startup_snvsaf7.png
Figure 10. Start-Up