SNVSB23 March   2018 LP87521-Q1 , LP87522-Q1 , LP87523-Q1 , LP87524-Q1 , LP87525-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Simplified Schematic
  3. 3 Description
    1.     Efficiency vs Output Current
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 I2C Serial Bus Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Descriptions
      1. 8.3.1 Multi-Phase DC/DC Converters
        1. 8.3.1.1 Overview
        2. 8.3.1.2 Multiphase Operation, Phase Adding, and Phase-Shedding
        3. 8.3.1.3 Transition Between PWM and PFM Modes
        4. 8.3.1.4 Multiphase Switcher Configurations
        5. 8.3.1.5 Buck Converter Load-Current Measurement
        6. 8.3.1.6 Spread-Spectrum Mode
      2. 8.3.2 Sync Clock Functionality
      3. 8.3.3 Power-Up
      4. 8.3.4 Regulator Control
        1. 8.3.4.1 Enabling and Disabling Regulators
        2. 8.3.4.2 Changing Output Voltage
      5. 8.3.5 Enable and Disable Sequences
      6. 8.3.6 Device Reset Scenarios
      7. 8.3.7 Diagnosis and Protection Features
        1. 8.3.7.1 Power-Good Information (PGOOD Pin)
        2. 8.3.7.2 Warnings for Diagnosis (Interrupt)
          1. 8.3.7.2.1 Output Power Limit
          2. 8.3.7.2.2 Thermal Warning
        3. 8.3.7.3 Protection (Regulator Disable)
          1. 8.3.7.3.1 Short-Circuit and Overload Protection
          2. 8.3.7.3.2 Overvoltage Protection
          3. 8.3.7.3.3 Thermal Shutdown
        4. 8.3.7.4 Fault (Power Down)
          1. 8.3.7.4.1 Undervoltage Lockout
      8. 8.3.8 GPIO Signal Operation
      9. 8.3.9 Digital Signal Filtering
    4. 8.4 Device Functional Modes
      1. 8.4.1 Modes of Operation
    5. 8.5 Programming
      1. 8.5.1 I2C-Compatible Interface
        1. 8.5.1.1 Data Validity
        2. 8.5.1.2 Start and Stop Conditions
        3. 8.5.1.3 Transferring Data
        4. 8.5.1.4 I2C-Compatible Chip Address
        5. 8.5.1.5 Auto-Increment Feature
    6. 8.6 Register Maps
      1. 8.6.1 Register Descriptions
        1. 8.6.1.1  OTP_REV
        2. 8.6.1.2  BUCK0_CTRL1
        3. 8.6.1.3  BUCK1_CTRL1
        4. 8.6.1.4  BUCK2_CTRL1
        5. 8.6.1.5  BUCK3_CTRL1
        6. 8.6.1.6  BUCK0_VOUT
        7. 8.6.1.7  BUCK0_FLOOR_VOUT
        8. 8.6.1.8  BUCK1_VOUT
        9. 8.6.1.9  BUCK1_FLOOR_VOUT
        10. 8.6.1.10 BUCK2_VOUT
        11. 8.6.1.11 BUCK2_FLOOR_VOUT
        12. 8.6.1.12 BUCK3_VOUT
        13. 8.6.1.13 BUCK3_FLOOR_VOUT
        14. 8.6.1.14 BUCK0_DELAY
        15. 8.6.1.15 BUCK1_DELAY
        16. 8.6.1.16 BUCK2_DELAY
        17. 8.6.1.17 BUCK3_DELAY
        18. 8.6.1.18 GPIO2_DELAY
        19. 8.6.1.19 GPIO3_DELAY
        20. 8.6.1.20 RESET
        21. 8.6.1.21 CONFIG
        22. 8.6.1.22 INT_TOP1
        23. 8.6.1.23 INT_TOP2
        24. 8.6.1.24 INT_BUCK_0_1
        25. 8.6.1.25 INT_BUCK_2_3
        26. 8.6.1.26 TOP_STAT
        27. 8.6.1.27 BUCK_0_1_STAT
        28. 8.6.1.28 BUCK_2_3_STAT
        29. 8.6.1.29 TOP_MASK1
        30. 8.6.1.30 TOP_MASK2
        31. 8.6.1.31 BUCK_0_1_MASK
        32. 8.6.1.32 BUCK_2_3_MASK
        33. 8.6.1.33 SEL_I_LOAD
        34. 8.6.1.34 I_LOAD_2
        35. 8.6.1.35 I_LOAD_1
        36. 8.6.1.36 PGOOD_CTRL1
        37. 8.6.1.37 PGOOD_CTRL2
        38. 8.6.1.38 PGOOD_FLT
        39. 8.6.1.39 PLL_CTRL
        40. 8.6.1.40 PIN_FUNCTION
        41. 8.6.1.41 GPIO_CONFIG
        42. 8.6.1.42 GPIO_IN
        43. 8.6.1.43 GPIO_OUT
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 Inductor Selection
        2. 9.2.1.2 Input Capacitor Selection
        3. 9.2.1.3 Output Capacitor Selection
        4. 9.2.1.4 Snubber Components
        5. 9.2.1.5 Supply Filtering Components
        6. 9.2.1.6 Current Limit vs. Maximum Output Current
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Community Resources
    6. 12.6 Trademarks
    7. 12.7 Electrostatic Discharge Caution
    8. 12.8 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RNF|26
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Pin Configuration and Functions

RNF Package
26-Pin VQFN-HR With Thermal Pad
Top View
LP87521-Q1 LP87522-Q1 LP87523-Q1 LP87524-Q1 LP87525-Q1 Ballmap_56.gif

Pin Functions

PIN TYPE(1) DESCRIPTION
NO. NAME
1 FB_B2 A Output voltage feedback (positive) for the BUCK2 converter.
2 EN3 D/I/O Programmable enable signal for the buck regulators (can be also configured to select between two buck output-voltage levels). This pin functions alternatively as GPIO3.
3 CLKIN D/I External clock input. Connect this pin to ground if the external clock is not used.
4, 17, Thermal Pad AGND G Ground
5 SCL D/I Serial interface clock input for I2C access. Connect this pin to a pullup resistor.
6 SDA D/I/O Serial interface data input and output for I2C access. Connect this pin to a pullup resistor.
7 EN1 D/I/O Programmable enable signal for the buck regulators (can be also configured to select between two buck output voltage levels). This pin functions alternatively as GPIO1.
8 FB_B0 A Output voltage feedback (positive) for the BUCK0 converter.
9 VIN_B0 P Input for the BUCK0 converter. The separate power pins, VIN_Bx, are not connected together internally. The VIN_Bx pins must be connected together in the application and be locally bypassed.
10 SW_B0 A BUCK0 switch node
11 PGND_B01 G Power ground for the BUCK0 and BUCK1 converters
12 SW_B1 A BUCK1 switch node
13 VIN_B1 P Input for the BUCK1 converter. The separate power pins, VIN_Bx, are not connected together internally. The VIN_Bx pins must be connected together in the application and be locally bypassed.
14 FB_B1 A Output voltage feedback (positive) for the BUCK1 converter. This pin functions alternatively as the output ground feedback (negative) for the BUCK0 converter.
15 EN2 D/I/O Programmable enable signal for the buck regulators (can be also configured to select between two buck output voltage levels). This pin functions alternatively as GPIO2.
16 PGOOD D/O Power-good indication signal
18 VANA P Supply voltage for the analog and digital blocks. This pin must be connected to the same node as VIN_Bx.
19 nINT D/O Open-drain interrupt output. This pin is active low.
20 NRST D/I Reset signal for the device
21 FB_B3 A Output voltage feedback (positive) for the BUCK3 converter. This pin functions alternatively as the output ground feedback (negative) for the BUCK2 converter.
22 VIN_B3 P Input for the BUCK3 converter. The separate power pins, VIN_Bx, are not connected together internally. The VIN_Bx pins must be connected together in the application and be locally bypassed.
23 SW_B3 A BUCK3 switch node
24 PGND_B23 G Power ground for the BUCK2 and BUCK3 converters
25 SW_B2 A BUCK2 switch node
26 VIN_B2 P Input for the BUCK2 converter. The separate power pins, VIN_Bx, are not connected together internally. The VIN_Bx pins must be connected together in the application and be locally bypassed.
(1) A: Analog Pin, D: Digital Pin, G: Ground Pin, P: Power Pin, I: Input Pin, O: Output Pin