SBASAC2 june   2023 AFE43902-Q1 , AFE53902-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configuration and Functions
  7. 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: Voltage Output
    6. 6.6  Electrical Characteristics: ADC Input
    7. 6.7  Electrical Characteristics: General
    8. 6.8  Timing Requirements: I2C Standard Mode
    9. 6.9  Timing Requirements: I2C Fast Mode
    10. 6.10 Timing Requirements: I2C Fast Mode Plus
    11. 6.11 Timing Requirements: SPI Write Operation
    12. 6.12 Timing Requirements: SPI Read and Daisy Chain Operation (FSDO = 0)
    13. 6.13 Timing Requirements: SPI Read and Daisy Chain Operation (FSDO = 1)
    14. 6.14 Timing Requirements: PWM Output
    15. 6.15 Timing Diagrams
    16. 6.16 Typical Characteristics: Voltage Output
    17. 6.17 Typical Characteristics: ADC
    18. 6.18 Typical Characteristics: General
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Smart Analog Front End (AFE) Architecture
      2. 7.3.2 Programming Interface
      3. 7.3.3 Nonvolatile Memory (NVM)
        1. 7.3.3.1 NVM Cyclic Redundancy Check (CRC)
          1. 7.3.3.1.1 NVM-CRC-FAIL-USER Bit
          2. 7.3.3.1.2 NVM-CRC-FAIL-INT Bit
      4. 7.3.4 Power-On Reset (POR)
      5. 7.3.5 External Reset
      6. 7.3.6 Register-Map Lock
    4. 7.4 Device Functional Modes
      1. 7.4.1 Digital-to-Analog Converter (DAC) Mode
        1. 7.4.1.1 Voltage Reference and DAC Transfer Function
          1. 7.4.1.1.1 Power-Supply as Reference
          2. 7.4.1.1.2 Internal Reference
          3. 7.4.1.1.3 External Reference
      2. 7.4.2 Pulse-Width Modulation (PWM) Mode
      3. 7.4.3 Analog-to-Digital Converter (ADC) Mode
      4. 7.4.4 Multislope Thermal Foldback Mode
        1. 7.4.4.1 Thermistor Linearization
    5. 7.5 Programming
      1. 7.5.1 SPI Programming Mode
      2. 7.5.2 I2C Programming Mode
        1. 7.5.2.1 F/S Mode Protocol
        2. 7.5.2.2 I2C Update Sequence
          1. 7.5.2.2.1 Address Byte
          2. 7.5.2.2.2 Command Byte
        3. 7.5.2.3 I2C Read Sequence
    6. 7.6 Register Maps
      1. 7.6.1  NOP Register (address = 00h) [reset = 0000h]
      2. 7.6.2  DAC-x-VOUT-CMP-CONFIG Register (address = 15h, 03h) [reset = 0400h]
      3. 7.6.3  COMMON-CONFIG Register (address = 1Fh) [reset = 03F9h]
      4. 7.6.4  COMMON-TRIGGER Register (address = 20h) [reset = 0000h]
      5. 7.6.5  COMMON-PWM-TRIG Register (address = 21h) [reset = 0001h]
      6. 7.6.6  GENERAL-STATUS Register (address = 22h) [reset = 2068h]
      7. 7.6.7  DEVICE-MODE-CONFIG Register (address = 25h) [reset = 8040h]
      8. 7.6.8  INTERFACE-CONFIG Register (address = 26h) [reset = 0000h]
      9. 7.6.9  STATE-MACHINE-CONFIG0 Register (address = 27h) [reset = 0003h]
      10. 7.6.10 SRAM-CONFIG Register (address = 2Bh) [reset = 0000h]
      11. 7.6.11 SRAM-DATA Register (address = 2Ch) [reset = 0000h]
      12. 7.6.12 Xx-TEMPERATURE Register (SRAM address = 20h, 22h, 24h) [reset = 0000h]
      13. 7.6.13 Yx-TEMPERATURE Register (SRAM address = 21h, 23h, 25h) [reset = 0000h]
      14. 7.6.14 Xx-OUTPUT Register (SRAM address = 26h, 28h, 2Ah, 2Ch) [reset = 0000h]
      15. 7.6.15 Yx-OUTPUT Register (SRAM address = 27h, 29h, 2Bh, 2Dh) [reset = 0000h]
      16. 7.6.16 PWM-FREQUENCY Register (SRAM address = 2Eh) [reset = 0000h]
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Multislope Thermal Foldback Using the AFE53902-Q1 and Voltage Output
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Performance Plots
      2. 8.2.2 Multislope Thermal Foldback Using the AFE43902-Q1 and PWM Output
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Performance Plots
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

7.4.2 Pulse-Width Modulation (PWM) Mode

The AFEx3902-Q1 provides the 7-bit PWM output on the SDA/SCLK/PWM pin. Pull the VREF/MODE pin high to enable PWM functionality. Table 7-1 lists all the possible PWM frequency configurations.

Table 7-1 PWM Frequency Configuration
SRAM LOCATION PWM-FREQ PWM FREQUENCY
(kHz)		 DUTY CYCLE (%)
FOR CODE 1		 DUTY CYCLE (%)
FOR CODE 126
0x2E [11:7] 0 Invalid N/A N/A
1 48.828 4.88 95.12
2 24.414 2.44 97.56
3 16.276 1.63 98.37
4 12.207 1.22 98.44
5 8.138 0.81 98.44
6 6.104 0.78 98.44
7 3.052 0.78 98.44
8 2.035 0.78 98.44
9 1.526 0.78 98.44
10 1.221 0.78 98.44
11 1.017 0.78 98.44
12 0.872 0.78 98.44
13 0.763 0.78 98.44
14 0.678 0.78 98.44
15 0.610 0.78 98.44
16 0.555 0.78 98.44
17 0.509 0.78 98.44
18 0.470 0.78 98.44
19 0.436 0.78 98.44
20 0.407 0.78 98.44
21 0.381 0.78 98.44
22 0.359 0.78 98.44
23 0.339 0.78 98.44
24 0.321 0.78 98.44
25 0.305 0.78 98.44
26 0.291 0.78 98.44
27 0.277 0.78 98.44
28 0.265 0.78 98.44
29 0.254 0.78 98.44
30 0.244 0.78 98.44
31 0.218 0.78 98.44

The duty cycle of the PWM is proportional to the 7-bit code, 0d to 126d. Table 7-2 shows that code 127d corresponds to 100% duty cycle. The duty cycle 99.22% (127d/128d) is skipped to achieve 100% duty cycle using a 7-bit code.

Table 7-2 PWM Duty Cycle Setting
CODE DUTY-CYCLE DESCRIPTION
0 0% Always 0
1 0.78% Minimum linear duty cycle
x (x/128)% x = code between 2d and 125d, both included
126 98.44% Maximum linear duty cycle
127 100% Always 1. The duty cycle of 99.22% (127d/128d) is skipped.