SBVS313 June   2017 TPS7A85A

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 Voltage Regulation Features
        1. 7.3.1.1 DC Regulation
        2. 7.3.1.2 AC and Transient Response
      2. 7.3.2 System Start-Up Features
        1. 7.3.2.1 Programmable Soft Start (NR/SS)
        2. 7.3.2.2 Internal Sequencing
          1. 7.3.2.2.1 Enable (EN)
          2. 7.3.2.2.2 Undervoltage Lockout (UVLO) Control
          3. 7.3.2.2.3 Active Discharge
        3. 7.3.2.3 Power-Good Output (PG)
      3. 7.3.3 Internal Protection Features
        1. 7.3.3.1 Foldback Current Limit (ICL)
        2. 7.3.3.2 Thermal Protection (Tsd)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Regulation
      2. 7.4.2 Disabled
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 External Component Selection
        1. 8.1.1.1 Adjustable Operation
        2. 8.1.1.2 ANY-OUT Programmable Output Voltage
        3. 8.1.1.3 ANY-OUT Operation
        4. 8.1.1.4 Increasing ANY-OUT Resolution for LILO Conditions
        5. 8.1.1.5 Current Sharing
        6. 8.1.1.6 Recommended Capacitor Types
        7. 8.1.1.7 Input and Output Capacitor Requirements (CIN and COUT)
        8. 8.1.1.8 Feed-Forward Capacitor (CFF)
        9. 8.1.1.9 Noise-Reduction and Soft-Start Capacitor (CNR/SS)
      2. 8.1.2 Start-Up
        1. 8.1.2.1 Circuit Soft-Start Control (NR/SS)
          1. 8.1.2.1.1 Inrush Current
        2. 8.1.2.2 Undervoltage Lockout (UVLO)
        3. 8.1.2.3 Power-Good (PG) Function
      3. 8.1.3 AC and Transient Performance
        1. 8.1.3.1 Power-Supply Rejection Ratio (PSRR)
        2. 8.1.3.2 Output Voltage Noise
        3. 8.1.3.3 Optimizing Noise and PSRR
          1. 8.1.3.3.1 Charge Pump Noise
        4. 8.1.3.4 Load Transient Response
      4. 8.1.4 DC Performance
        1. 8.1.4.1 Output Voltage Accuracy (VOUT)
        2. 8.1.4.2 Dropout Voltage (VDO)
          1. 8.1.4.2.1 Behavior When Transitioning From Dropout Into Regulation
      5. 8.1.5 Sequencing Requirements
      6. 8.1.6 Negatively Biased Output
      7. 8.1.7 Reverse Current
      8. 8.1.8 Power Dissipation (PD)
        1. 8.1.8.1 Estimating Junction Temperature
        2. 8.1.8.2 Recommended Area for Continuous Operation (RACO)
    2. 8.2 Typical Applications
      1. 8.2.1 Low-Input, Low-Output (LILO) Voltage Conditions
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
  9. Power-Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example

Package Options

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

Specifications

Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Voltage IN, BIAS, PG, EN –0.3 7 V
IN, BIAS, PG, EN (5% duty cycle, pulse duration = 200 μs) –0.3 7.5 V
SNS, OUT –0.3 VIN + 0.3 V
NR/SS, FB –0.3 3.6 V
50mV, 100mV, 200mV, 400mV, 800mV, 1.6V –0.3 VOUT + 0.3 V
Current OUT Internally limited Internally limited A
PG (sink current into device) 5 mA
Operating junction temperature, TJ –55 150 °C
Storage temperature, Tstg –55 150 °C
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.

ESD Ratings

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) ±500
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. Manufacturing with less than 500-V HBM is possible with the necessary precautions. Pins listed as ±2000 V may actually have higher performance.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. Manufacturing with less than 250-V CDM is possible with the necessary precautions. Pins listed as ±500 V may actually have higher performance.

Recommended Operating Conditions

over junction temperature range (unless otherwise noted)
MIN NOM MAX UNIT
VIN Input supply voltage range 1.1 6.5 V
VBIAS Bias supply voltage range(1) 3 6.5 V
VOUT Output voltage range(2) 0.8 5.1 V
VEN Enable voltage range 0 VIN V
IOUT Output current 0 4 A
CIN Input capacitor 10 47 μF
COUT Output capacitor 47 47 || 10 || 10 (3) μF
CBIAS BIAS Capacitor 10 μF
RPG Power-good pullup resistance 10 100
CNR/SS NR/SS capacitor 10 nF
CFF Feed-forward capacitor 10 nF
R1 Top resistor value in feedback network for adjustable operation 12.1 (4)
R2 Bottom resistor value in feedback network for adjustable operation 160 (5)
TJ Operating junction temperature –40 125 °C
BIAS supply is required when the VIN supply is below 1.4 V. Conversely, no BIAS supply is required when the VIN supply is higher than or equal to 1.4 V. A BIAS supply helps improve dc and ac performance for VIN ≤ 2.2 V.
This output voltage range does not include device accuracy or accuracy of the feedback resistors.
The recommended output capacitors are selected to optimize PSRR for the frequency range of 400 kHz to 700 kHz. This frequency range is a typical value for dc-dc supplies.
The 12.1-kΩ resistor is selected to optimize PSRR and noise by matching the internal R1 value.
The upper limit for the R2 resistor is to ensure accuracy by making the current through the feedback network much larger than the leakage current into the feedback node.

Thermal Information

THERMAL METRIC(1) TPS7A85A UNIT
RGR (VQFN)
20 PINS
RθJA Junction-to-ambient thermal resistance 43.4 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 36.8 °C/W
RθJB Junction-to-board thermal resistance 17.6 °C/W
ψJT Junction-to-top characterization parameter 0.8 °C/W
ψJB Junction-to-board characterization parameter 17.6 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance 3.4 °C/W
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

Electrical Characteristics

over operating junction temperature range (TJ = –40°C to +125°C), VIN = 1.4 V or VIN = VOUT(nom) + 0.5 V (whichever is greater), VBIAS = open, VOUT(nom) = 0.8 V(2), OUT connected to 50 Ω to GND(3), VEN = 1.1 V, CIN = 10 μF, COUT = 47 μF, CNR/SS = 0 nF, CFF = 0 nF, and PG pin pulled up to VIN with 100 kΩ unless otherwise noted. Typical values are at TJ = 25°C.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VIN Input supply voltage range(1) 1.1 6.5 V
VBIAS Bias supply voltage range(1) VIN = 1.1 V 3 6.5 V
VFB Feedback voltage 0.8 V
VNR/SS NR/SS pin voltage 0.8 V
VUVLO1(IN) Input supply UVLO with BIAS VIN rising with VBIAS = 3 V 1.02 1.085
VHYS1(IN) VUVLO1(IN) hysteresis VBIAS = 3 V 320 mV
VUVLO2(IN) Input supply UVLO without BIAS VIN rising 1.31 1.39 V
VHYS2(IN) VUVLO2(IN) hysteresis 253 mV
VUVLO(BIAS) Bias supply UVLO VBIAS rising
VIN = 1.1 V
2.83 2.9 V
VHYS(BIAS) VUVLO(BIAS) hysteresis VIN = 1.1 V 290 mV
VOUT Output voltage Range Using the ANY-OUT pins 0.8 – 1% 3.95 + 1% V
Using external resistors(4) 0.8 – 1% 5.1 + 1%
Accuracy(4) (5) 0.8 V ≤ VOUT ≤ 5.1 V (6)
5 mA ≤ IOUT ≤ 4 A
1.4 V ≤ VIN ≤ 6.5 V
–1% 1%
Accuracy with BIAS 1.1V ≤ VIN ≤ 2.2 V
0.8 V ≤ VOUT ≤ 1.9 V
5 mA ≤ IOUT ≤ 4 A
3 V ≤ VBIAS ≤ 6.5 V
–0.75% 0.75%
ΔVOUT / ΔVIN Line regulation IOUT = 5 mA
1.4 V ≤ VIN ≤ 6.5 V
0.0035 mV/V
ΔVOUT / ΔIOUT Load regulation 5 mA ≤ IOUT ≤ 4 A
3 V ≤ VBIAS ≤ 6.5 V
VIN = 1.1 V
0.07 mV/A
5 mA ≤ IOUT ≤ 4 A 0.08
5 mA ≤ IOUT ≤ 4 A
VOUT = 5.1 V
0.4
VDO Dropout voltage VIN = 1.4 V
IOUT = 4 A
VFB = 0.8 V – 3%
215 320 mV
VIN = 5.5 V
IOUT = 4 A
VFB = 0.8 V – 3%
325 500
VIN = 1.1 V
VBIAS = 5 V
IOUT = 4 A
VFB = 0.8 V – 3%
150 240
VIN = 5.7 V
IOUT = 4 A
VFB = 0.8 V – 3%
600
ILIM Output current limit VOUT forced at 0.9 × VOUT(nom),
VIN = VOUT(nom) + 0.4 V
4.7 5.2 5.7 A
ISC Short-circuit current limit RLOAD = 20 mΩ 1 A
IGND GND pin current VIN = 6.5 V
IOUT = 5 mA
2.8 4 mA
VIN = 1.4 V
IOUT = 4 A
4.8 6
Shutdown, PG = open, VIN = 6.5 V
VEN = 0.5 V
25 µA
IEN EN pin current VIN = 6.5 V
VEN = 0 V and 6.5 V
–0.1 0.1 µA
IBIAS BIAS pin current VIN = 1.1 V
VBIAS = 6.5 V
VOUT(nom) = 0.8 V
IOUT = 4 A
2.3 3.5 mA
VIL(EN) EN pin low-level input voltage
(disable device)
0 0.5 V
VIH(EN) EN pin high-level input voltage
(enable device)
1.1 6.5 V
VIT(PG) PG pin threshold For falling VOUT 82% × VOUT 88.3% × VOUT 93% × VOUT V
VHYS(PG) PG pin hysteresis For rising VOUT 1% × VOUT V
VOL(PG) PG pin low-level output voltage VOUT < VIT(PG)
IPG = –1 mA (current into device)
0.4 V
Ilkg(PG) PG pin leakage current VOUT > VIT(PG)
VPG = 6.5 V
1 µA
INR/SS NR/SS pin charging current VNR/SS = GND
VIN = 6.5 V
4 6.2 9 µA
IFB FB pin leakage current VIN = 6.5 V –100 100 nA
PSRR Power-supply ripple rejection VIN – VO UT = 0.5 V
IOUT = 4 A
CNR/SS = 100 nF
CFF = 10 nF
COUT =
47 μF || 10 μF || 10 μF
f = 10 kHz
VOUT = 0.8 V
VBIAS = 5 V
42 dB
f = 500 kHz
VOUT = 0.8 V
VBIAS = 5 V
39
f = 10 kHz
VOUT = 5 V
40
f = 500 kHz
VOUT = 5 V
25
Vn Output noise voltage Bandwidth = 10 Hz to 100 kHz, VIN = 1.1 V
VOUT = 0.8 V
VBIAS = 5 V
IOUT = 4 A
CNR/SS = 100 nF
CFF = 10 nF
COUT = 47 μF || 10 μF || 10 μF
4.4 μVRMS
Bandwidth = 10 Hz to 100 kHz
VOUT = 5 V
IOUT = 4 A
CNR/SS = 100 nF
CFF = 10 nF
COUT = 47 μF || 10 μF || 10 μF
8.4
Tsd Thermal shutdown temperature Shutdown, temperature increasing 160 °C
Reset, temperature decreasing 140
TJ Operating junction temperature –40 125 °C
BIAS supply is required when the VIN supply is below 1.4 V. Conversely, no BIAS supply is required when the VIN supply is higher than or equal to 1.4 V. A BIAS supply helps improve dc and ac performance for VIN ≤ 2.2 V.
VOUT(nom) is the calculated VOUT target value from the ANY-OUT in a fixed configuration. In an adjustable configuration, VOUT(nom) is the expected VOUT value set by the external feedback resistors.
This 50-Ω load is disconnected when the test conditions specify an IOUT value.
When the device is connected to external feedback resistors at the FB pin, external resistor tolerances are not included.
The device is not tested under conditions where VIN > VOUT + 1.25 V and IOUT = 4 A because the power dissipation is higher than the maximum rating of the package.
For VOUT ≤ 5 V, VIN = VOUT + 0.5 V. For VOUT > 5 V, VIN = VOUT + 0.6 V.

Typical Characteristics

at TA = 25°C, VIN = 1.4 V or VIN = VOUT(NOM) + 0.5 V (whichever is greater), VBIAS = open, VOUT(NOM) = 0.8 V, VEN = 1.1 V, COUT = 47 μF, CNR/SS = 0 nF, CFF = 0 nF, and PG pin pulled up to VIN with 100 kΩ (unless otherwise noted)
TPS7A85A PSRR_vs_Iout.gif
VIN = 1.2 V, VBIAS = 5 V,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 1. PSRR vs Frequency and IOUT
TPS7A85A PSRR_vs_Vbias.gif
VIN = 1.4 V, IOUT = 1 A,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 3. PSRR vs Frequency and VBIAS
TPS7A85A PSRR_vs_Vout_with_Bias.gif
VIN = VOUT + 0.4 V, VBIAS = 5.0 V, IOUT = 4 A,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 5. PSRR vs Frequency and VOUT With Bias
TPS7A85A PSRR_vs_Cout.gif
VIN = 5.6 V, COUT = 47 μF || 10 μF || 10 μF,
CNR/SS = 10 nF, CFF = 10 nF
Figure 7. PSRR vs Frequency and COUT
TPS7A85A PSRR_vs_Vin_5Vout.gif
IOUT = 4 A, COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF,
CFF = 10 nF
Figure 9. PSRR vs Frequency and VIN for VOUT = 5 V
TPS7A85A Noise_vs_Vout_Iout.gif
VIN = VOUT + 0.4 V and VBIAS = 5 V for VOUT ≤ 2.2 V,
RMS Noise BW = 10 Hz to 100 kHz,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 11. Output Voltage Noise vs Output Voltage
TPS7A85A Noise_vs_Vin.gif
IOUT = 1 A, RMS Noise BW = 10 Hz to 100 kHz,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 13. Output Noise vs Frequency and VIN
TPS7A85A Noise_vs_Cff.gif
VIN = VOUT + 0.4 V, VBIAS = 5 V, IOUT = 4 A,
RMS Noise BW = 10 Hz to 100 kHz,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF
Figure 15. Output Noise vs Frequency and CFF
TPS7A85A Startup_Vs_Cnr.gif
VIN = 1.2 V, VOUT = 0.9 V, VBIAS = 5.0 V, IOUT = 4 A,
COUT = 47 μF || 10 μF || 10 μF, CFF = 10 nF
Figure 17. Start-Up Waveform vs Time and CNR/SS
TPS7A85A Load_trans_vs_Vout_no_Bias.gif
IOUT, DC = 100 mA, COUT = 47 μF || 10 μF || 10 μF,
CNR/SS = CFF = 10 nF, slew rate = 1 A/μs
Figure 19. Load Transient Waveform vs
Time and VOUT Without Bias
TPS7A85A Load_Trans_vs_Cout.gif
VIN = 1.2 V, VBIAS = 5.0 V, IOUT = 100 mA to 4 A,
CNR/SS = CFF = 10 nF, slew rate = 1 A/μs
Figure 21. Load Transient Waveform vs Time and COUT
(VOUT = 0.9 V)
TPS7A85A D001_SBVS267.gif
IOUT = 4 A, VBIAS = 0 V
Figure 23. Dropout Voltage vs Input Voltage Without Bias
TPS7A85A D003_SBVS267.gif
VIN = 1.4 V, VBIAS = 0 V
Figure 25. Dropout Voltage vs Output Current Without Bias
TPS7A85A D005_SBVS267.gif
VIN = 5.5 V
Figure 27. Dropout Voltage vs Output Current (High VIN)
TPS7A85A D006_SBVS267.gif
Figure 29. Load Regulation (0.8-V Output)
TPS7A85A D010_SBVS267.gif
Figure 31. Load Regulation (5-V Output)
TPS7A85A D012_SBVS267.gif
VIN = 1.1 V, IOUT = 5 mA
Figure 33. Line Regulation vs Bias Voltage
TPS7A85A D015_SBVS267.gif
IOUT = 5 mA
Figure 35. Ground Pin Current vs Input Voltage
TPS7A85A D017_SBVS267.gif
Figure 37. Shutdown Current vs Input Voltage
TPS7A85A D019_SBVS267.gif
Figure 39. NR/SS Charging Current vs Input Voltage
TPS7A85A D022_SBVS267.gif
VIN = 1.1 V
Figure 41. VBIAS UVLO vs Temperature
TPS7A85A D024_SBVS267.gif
Figure 43. PG Voltage vs PG Current Sink
TPS7A85A D026_SBVS267.gif
Figure 45. PG Threshold vs Temperature
TPS7A85A PSRR_vs_Vin_with_Bias.gif
IOUT = 4 A, VBIAS = 5 V,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 2. PSRR vs Frequency and VIN With Bias
TPS7A85A PSRR_vs_VIN.gif
IOUT = 1 A,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 4. PSRR vs Frequency and VIN
TPS7A85A PSRR_vs_Vin_3p3Vout.gif
IOUT = 4 A, COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF,
CFF = 10 nF
Figure 6. PSRR vs Frequency and VIN for VOUT = 3.3 V
TPS7A85A PSRR_vs_Iout_5Vout.gif
VIN = VOUT + 0.6 V, IOUT = 4 A,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 8. PSRR vs Frequency and IOUT for VOUT = 5 V
TPS7A85A 7a85_Bias_PSRR.gif
VIN = VOUT + 0.4 V, VOUT = 1 V, IOUT = 4 A,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 10. VBIAS PSRR vs Frequency
TPS7A85A Noise_vs_Vout.gif
VIN = VOUT + 0.4 V and VBIAS = 5 V for VOUT ≤ 2.2 V, IOUT = 4 A, RMS Noise BW = 10 Hz to 100 kHz,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = 10 nF, CFF = 10 nF
Figure 12. Output Noise vs Frequency and VOUT
TPS7A85A Noise_vs_Cnr.gif
VIN = VOUT + 0.4 V, VBIAS = 5 V, IOUT = 4 A,
RMS Noise BW = 10 Hz to 100 kHz,
COUT = 47 μF || 10 μF || 10 μF, CFF = 10 nF
Figure 14. Output Noise vs Frequency and CNR/SS
TPS7A85A Noise_vs_Cnr_Cff_5Vout.gif
VIN = 5.6 V, IOUT = 4 A, RMS Noise BW = 10 Hz to 100 kHz,
COUT = 47 μF || 10 μF || 10 μF, CFF = 10 nF
Figure 16. Output Noise at 5.0-V Output vs CNR/SS and CFF
TPS7A85A Load_trans_vs_Vout_with_Bias.gif
VIN = VOUT + 0.3 V, VBIAS = 5 V, IOUT, DC = 100 mA, slew rate = 1 A/μs, CNR/SS = CFF = 10 nF, COUT = 47 μF || 10 μF || 10 μF
Figure 18. Load Transient Waveform vs Time and
VOUT With Bias
TPS7A85A load_trans_vs_SR_5Vout.gif
VOUT = 5 V, IOUT, DC = 100 mA, IOUT = 100 mA to 4 A,
COUT = 47 μF || 10 μF || 10 μF, CNR/SS = CFF = 10 nF
Figure 20. Load Transient Waveform vs
Time and Slew Rate
TPS7A85A Load_trans_vs_preload.gif
VIN = 1.2 V, VBIAS = 5.0 V, COUT = 47 μF || 10 μF || 10 μF,
CNR/SS = CFF = 10 nF, slew rate = 1 A/μs
Figure 22. Load Transient Waveform vs Time and DC Load
(VOUT = 0.9 V)
TPS7A85A D002_SBVS267.gif
IOUT = 4 A, VBIAS = 6.5 V
Figure 24. Dropout Voltage vs Input Voltage With Bias
TPS7A85A D004_SBVS267.gif
VIN = 1.1 V, VBIAS = 3 V
Figure 26. Dropout Voltage vs Output Current With Bias
TPS7A85A Load_reg_vs_Vout.gif
IOUT = 100 mA to 4 A
Figure 28. Load Regulation vs Output Voltage
TPS7A85A D008_SBVS267.gif
Figure 30. Load Regulation (3.3-V Output)
TPS7A85A D011_SBVS267.gif
IOUT = 5 mA
Figure 32. Line Regulation Without Bias
TPS7A85A D014_SBVS267.gif
IOUT = 5 mA
Figure 34. Line Regulation (5-V Output)
TPS7A85A D016_SBVS267.gif
VIN = 1.1 V, IOUT = 5 mA
Figure 36. Bias Pin Current vs Bias Voltage
TPS7A85A D018_SBVS267.gif
VIN = 1.1 V
Figure 38. Shutdown Current vs Bias Voltage
TPS7A85A UVLO_Vin.gif
Figure 40. VIN UVLO vs Temperature
TPS7A85A D023_SBVS267.gif
Figure 42. Enable Threshold vs Temperature
TPS7A85A D025_SBVS267.gif
VIN = 6.5 V
Figure 44. PG Voltage vs PG Current Sink