SLVSCX0B February   2016  – April 2016 TPS62770

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1. 5.1 Output Voltage Setting Step-Down Converter
  6. 6 Specifications
    1. 6.1 ESD Ratings
    2. 6.2 Thermal Information
    3. 6.3 Electrical Characteristics
    4. 6.4 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 Step-Down Converter Device
        1. 7.3.1.1 DCS-Control
        2. 7.3.1.2 Output Voltage Selection with pins VSEL1-VSEL3
        3. 7.3.1.3 CTRL / Output Load
        4. 7.3.1.4 Output Discharge At Pins VO1 And LOAD
        5. 7.3.1.5 Undervoltage Lockout UVLO
        6. 7.3.1.6 Short Circuit Protection
      2. 7.3.2 Step-Up Converter Device
        1. 7.3.2.1 Under-Voltage Lockout
        2. 7.3.2.2 Output Disconnect
        3. 7.3.2.3 12 V Fixed Output Voltage
        4. 7.3.2.4 Mode Selection With Pin BM
        5. 7.3.2.5 Output Overvoltage Protection
        6. 7.3.2.6 Output Short Circuit Protection
        7. 7.3.2.7 PWM to Analog Converter AT PIN EN2/PWM
    4. 7.4 Device Functional Modes
      1. 7.4.1 Step-Down Converter
        1. 7.4.1.1 Enable and Shutdown
        2. 7.4.1.2 Power Save Mode Operation
        3. 7.4.1.3 PWM Mode Operation
        4. 7.4.1.4 Device Start-up and Soft Start
        5. 7.4.1.5 Automatic Transition Into 100% Mode
      2. 7.4.2 Step-Up Converter
        1. 7.4.2.1 Enable and Shutdown
        2. 7.4.2.2 Soft Start
        3. 7.4.2.3 Power Save Mode
        4. 7.4.2.4 PWM Mode
        5. 7.4.2.5 Constant-Current Step-Up Mode Operation
        6. 7.4.2.6 Constant-Voltage Step-Up Mode Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 TPS62770 Step-Down Converter + Load Switch
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Setting The Output Voltage Of The Step-Down Converter
          2. 8.2.1.2.2 Inductor Selection Step-Down Converter
          3. 8.2.1.2.3 Input and Output Capacitor Selection
        3. 8.2.1.3 Application Curves - TPS62770 Step-Down Converter + Load Switch
      2. 8.2.2 TPS62770 Step-Up Converter with Adjustable Output Voltage (9 V to 15 V)
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Programming the Output Voltage Of The Step-Up Converter
          2. 8.2.2.2.2 Inductor Selection for TPS62770 Step-Up Converter
            1. 8.2.2.2.2.1 Example Step-Up Converter with 12-V Fixed Output
        3. 8.2.2.3 Application Curves for Step-Up Converter
      3. 8.2.3 Step-Up Converter with Constant 5-V Output Voltage
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
        3. 8.2.3.3 Application Performance Curves
      4. 8.2.4 Typical Step Up Converter with Constant Output Current
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Detailed Design Procedure
          1. 8.2.4.2.1 Setting the Output Current
          2. 8.2.4.2.2 Inductor Selection
        3. 8.2.4.3 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 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

6 Specifications

Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)
MIN MAX UNIT
Pin voltage(2) VIN, FB –0.3 6 V
SW1 –0.3 VIN +0.3V V
EN1, EN2/PWM, CTRL, BM, VSEL1-3 –0.3 VIN +0.3V V
SW2, VO2 -0.3 32 V
VO1, LOAD –0.3 3.7 V
TJ Operating junction temperature range –40 125 °C
Tstg Storage temperature range –65 150 °C
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.
(2) All voltage values are with respect to network ground terminal GND.

6.1 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) ±500
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. The human body model is a 100-pF capacitor discharged through a 1.5-kΩ resistor into each pin.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

Recommended Operating Conditions

MIN NOM MAX UNIT
VIN Input voltage range at VIN pin 2.5 5.5 V
IOUT1 DC/DC 1 Step down converter output current L1 = 2.2µH, COUT1 = 10 µF 300 mA
IOUT2 DC/DC 2 Step up converter output current 2.5V < VIN < 5.5V, VOUT2 = 12V, COUT2 = 10uF, L = 10µH 30 mA
2.5V < VIN < 5.5V, VOUT2 = 12V, COUT2 = 2x 10uF, L = 10µH 100
3V < VIN < 5.5V, VOUT2 = 5V, COUT2 = 2x 10uF, L = 4.7µH 200
ILOAD Load current (current from LOAD pin) 100
TJ Operating junction temperature range -40 125 °C
TA Ambient temperature range -40 85

6.2 Thermal Information

THERMAL METRIC(1) TPS62770 UNIT
YFP
TERMINALS
RθJA Junction-to-ambient thermal resistance 90.6 °C/W
RθJCtop Junction-to-case (top) thermal resistance 0.6
RθJB Junction-to-board thermal resistance 13.8
ψJT Junction-to-top characterization parameter 2.8
ψJB Junction-to-board characterization parameter 13.7
RθJCbot Junction-to-case (bottom) thermal resistance n/a
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.3 Electrical Characteristics

VIN = 3.6V, TA = –40°C to 85°C typical values are at TA = 25°C (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY
ISD Shutdown current into VIN EN1 = EN2/PWM = GND, CTRL GND, BM = GND, 0.1 1850 nA
VTH_ UVLO+ Undervoltage lockout threshold Rising VIN 2.1 2.22 V
VTH_UVLO- Falling VIN 1.9 2
INPUTS EN1, EN2/PWM, BM, CTRL,VSEL 1-3
VIH TH High level input threshold 1.2 V
VIL TH Low level input threshold 0.4 V
IIN Input bias Current TJ = 25°C 10 nA
TJ = –40°C to 85°C 25
STEP-DOWN CONVERTER
IQ Operating quiescent current EN1 = VIN, EN2/PWM = GND, CTRL = GND, IOUT = 0µA, VOUT = 1.8V, device not switching, 370 1850 nA
EN1 = VIN, EN2/PWM = GND, IOUT = 0mA, CTRL = GND, VOUT = 1.8V , device switching 500
VVOUT Output voltage range 1.0 3.0 V
Output voltage accuracy PFM mode -2.5 0 2.5 %
PWM mode -2 0 2
DC output voltage load regulation VOUT = 1.8V 0.001 %/mA
DC output voltage line regulation VOUT = 1.8V, IOUT = 10 mA, 2.5V ≤ VIN ≤ 5.5V 0 %/V
RDS(ON) High side MOSFET on-resistance IOUT = 50mA 0.45 Ω
Low Side MOSFET on-resistance 0.22
ILIMF High side MOSFET switch current limit 480 600 720 mA
Low side MOSFET switch current limit 600 mA
RDSCH_VO1 Discharge switch on-resistance EN = GND, IVO1 = -10mA into VO1 pin 20 65 Ω
IIN_VO1 Bias current into VO1 pin EN = VIN, VOUT = 1.8V TJ = 25°C 40 100 nA
TJ = –40°C to 85°C 1010
VTH_100+ Auto 100% Mode leave detection threshold (1) Rising VIN,100% Mode is left with VIN = VOUT + VTH_100+ , max value at TJ = 85°C 150 250 370 mV
VTH_100- Auto 100% Mode enter detection threshold (1) Falling VIN, 100% Mode is entered with VIN = VOUT + VTH_100-, max value at TJ = 85°C 85 200 310
tONmin Minimum ON time VOUT = 2.0V, IOUT = 0 mA 225 ns
tOFFmin Minimum OFF time 50 ns
tStartup_delay Regulator start up delay time From transition EN1 = low to high until device starts switching 1 5 ms
tSoftstart Softstart time with reduced switch current limit 700 1200 µs
ILIM_softstart High side MOSFET switch current limit Reduced switch current limit during softstart 80 150 200 mA
Low side MOSFET switch current limit 150
LOAD SWITCH
RLOAD MOSFET on-resistance ILOAD = 50mA, CTRL = VIN, VOUT = 1.8V, 0.6 1.27 Ω
trise_LOAD VLOAD rise time Starting with CTRL low to high transition, time to ramp VLOAD from 95%, VOUT = 1.8V, ILOAD = 20mA 315 800 μs
RDCHRG MOSFET on-resistance 20 65 Ω
STEP-UP CONVERTER
IQ_VIN Quiescent current into VIN pin EN2/PWM = VIN, BM = GND, EN1 = GND, no load, no switching, VOUT = 12 V 110 200 µA
VOUT Output voltage range EN2/PWM = VIN, BM = GND 4.5 15 V
VOUT_12V 12-V output voltage accuracy FB pin connected to VIN pin, EN2/PWM = VIN, BM = GND 11.7 12 12.3 V
VFB Feedback voltage PWM mode, BM = GND, EN2/PWM = VIN 0.775 0.795 0.814 V
PFM mode, BM = GND, EN2/PWM = VIN 0.803 V
Feedback regulation voltage under brightness control EN2/PWM = VIN, BM = VIN, 189 200 206 mV
VFB =50mV, BM = VIN, D(PWM) @ EN2/PWM = 25%, 40 50 60 mV
VFB = 20mV, BM = VIN, D(PWM) @ EN2/PWM = 10% 13 20 27
tDim_Off Dimming signal on pin EN2/PWM 270 160 μs
tDim_On 1 μs
VOVP Output overvoltage protection threshold 17 17.7 18.4 V
VOVP_HYS Over voltage protection hysteresis 800 mV
IFB_LKG Leakage current into FB pin 5 200 nA
ISW_LKG Leakage current into SW pin EN2/PWM = GND 5 500 nA
RDS(on) Isolation MOSFET on resistance VOUT = 12 V 850 mΩ
Low-side MOSFET on resistance VOUT = 12 V 450
fSW Switching frequency VOUT = 12 V, PWM mode 850 1050 1250 kHz
tON_min Minimal switch on time 150 250 ns
ILIM_SW Peak switch current limit VOUT = 12 V 730 970 1230 mA
ILIM_CHG Pre-charge current VOUT = 0 V 30 55 mA
tSoftstart Pre-charge time BM = GND, EN2/PWM from low to high until device starts switching, IOUT2 = 0mA, COUT2 = 10uF 6 ms
Startup time VOUT from VIN to 12 V, COUT_effective = 2.2 µF, IOUT = 0 A 6
(1) VIN is compared to the programmed output voltage (VOUT). When VIN–VOUT falls below VTH_100- the device enters 100% Mode by turning the high side MOSFET on. The 100% Mode is exited when VIN–VOUT exceeds VTH_100+ and the device starts switching. The hysteresis for the 100% Mode detection threshold VTH_100+ - VTH_100- will always be positive and will be approximately 50 mV(typ.)

6.4 Typical Characteristics

TPS62770 ATE_IQ_buck_vs_VIN_TEMP.gif
EN2/PWM = Low VOUT1 Set to 1.8 V
EN1 = High Device not Switching
Figure 1. Quiescent Current IQStep-Down converter
TPS62770 ATE_ISDN_vs_VIN_TEMP.gif
EN1 = EN2/PWM = Low
Figure 3. Shutdown Current ISDN
TPS62770 ATE_IQ_boost_vs_VIN_TEMP.gif
EN2/PWM = High VOUT2 Set to 12 V
EN1 = Low Device not Switching
Figure 2. Quiescent Current IQStep-Up converter