ADP5520 Analog Devices, ADP5520 Datasheet - Page 8

• Manufacturer Part Number: ADP5520
• Description: Backlight Driver with I/O Expander
• Manufacturer: Analog Devices

Specifications of ADP5520

• Vin Range: 2.7 to 5.5V
• Vout (v): 24 to 27
• Synchronous: No
• Package: 24-Lead LFCSP
• Led Configuration: Serial
• Topology: Inductive
• I2c Support: Yes
• Max Iout (ma): 30mA
• Brightness Control: I2C
• Switching Frequency: 1MHz
• Over Volt Protection (v): 24V

ADP5520
4
4
1
2
3
1
2
3
CH1 20.0V
CH3 10.0V
CH1 20.0V
CH3 10.0V
SW
INDUCTOR CURRENT
BST
BL_SNK
SW
INDUCTOR CURRENT
BST
BL_SNK
Figure 10. Boost Operation (Backlight = 15 mA)
Figure 9. Boost Operation (Backlight = 30 mA)
CH2 500mA
CH4 1.0V
CH2 500mA
CH4 1.0V
TIME (4µs/DIV)
TIME (4µs/DIV)
Rev. A | Page 8 of 40
4
4
1
2
3
1
2
3
CH1 20.0V
CH3 10.0V
CH1 10.0V
CH3 10.0V
SW
INDUCTOR CURRENT
BST
BL_SNK
INDUCTOR CURRENT
BST
BL_SNK
SW
Figure 11. Boost Operation (Backlight = 2 mA)
CH2 500mA
CH4 1.0V
CH2 500mA
CH4 1.0V
Figure 12. Boost Startup
TIME (1ms/DIV)
TIME (4µs/DIV)