帶攝像頭 PMIC 的可擴展汽車 200 萬像素攝像頭模塊參考設計 用于演示 DS90UB954-Q1 EVM 上的遠程解串器的生產編程示例。本參考設計中使用的這種成像儀是 Onsemi? AR0233。該圖像傳感器需要的電源序列不同于默認 TPS65033000-Q1 序列，并且不允許 1.8V IO 電源軌首先上電。由于這是雙板設計，在通過反向通道對 PMIC 進行重新編程期間，AR0233 圖像板僅處于斷開狀態。

連接 DS90UB954-Q1 EVM 并為其通電后，本地 PC 可以運行腳本來配置反向通道并執行圖 3-6 中的程序流。

import time# Set up IDs
UB954 = 0x60
UB953ID = 0x30
UB953 = 0x18
PMICID = 0xC0
PMIC = 0xC0

print "Configuring Back-Channel"

# Set up Port0
board.WriteI2C(UB954, 0x4C, 0x01)

# Set up Back Channel Config (0x58)
board.WriteI2C(UB954,0x58,0x5E)

# Set up SER ID
#board.WriteI2C(UB954,0x5B,UB953ID)
# Set up SER Alias ID
board.WriteI2C(UB954,0x5C,UB953)
# Set up Slave/PMIC ID
board.WriteI2C(UB954,0x5E,PMICID)
# Set up Slave/PMIC Alias ID
board.WriteI2C(UB954,0x66,PMIC)

time.sleep(0.1)

print "Reprogramming PMIC"

# Reprogram PMIC Power Sequence
board.WriteI2C(PMIC,0x02,0xDD)  # Unlock control registers
board.WriteI2C(PMIC,0x03,0x16)  # Disable Buck3 and LDO
board.WriteI2C(PMIC,0x04,0x1A)  # Disable the configuration CRC 
board.WriteI2C(PMIC,0x05,0xAA)  # Unlock configuration registers
board.WriteI2C(PMIC,0x0F,0x02)  # Reprogram power sequence
board.WriteI2C(PMIC,0x10,0x1A)
board.WriteI2C(PMIC,0x13,0x71)
board.WriteI2C(PMIC,0x14,0x42)
board.WriteI2C(PMIC,0x15,0x32)
board.WriteI2C(PMIC,0x16,0x52)
board.WriteI2C(PMIC,0x17,0x23)
board.WriteI2C(PMIC,0x03,0x1F)  # Enable Buck3 and LDO
board.WriteI2C(PMIC,0x0E,0x0A)  # Reprogram Buck2 power sequence
board.WriteI2C(PMIC,0x11,0x02)  # Configure nRSTOUT as global PGOOD
board.WriteI2C(PMIC,0x29,0xAE)  # Write new configuration CRC
board.WriteI2C(PMIC,0x04,0x1E)  # Enable configuration CRC
board.WriteI2C(PMIC,0x4A,0x2D)  # Write registers to EEPROM

time.sleep(1)
print "PMIC Reprogrammed"

圖 3-6 和圖 3-5 演示了 Analog LaunchPad 軟件的腳本執行情況。

圖 3-4 Analog LaunchPad SerDes 鏈路

圖 3-5 Analog LaunchPad“Scripting”窗口

圖 3-6 和圖 3-7 展示了重新編程前后的 PMIC 電源序列。

圖 3-6 TPS65033000 默認電源序列

圖 3-7 TPS65033000 在重新編程后的電源序列