For a special application, such as for high brightness and long-time focusing in camera module, the total current is 500 mA and focusing adjust time would be 10s or more, so at this condition, torch mode will meet this target.

Condition

• V_IN = 3.7 V
• I_{LED_total} = 500 mA, 2 channel are connected together, per channel provides 250 mA
• Torch mode
• Torch time = 2s
• V_{LED_Forward} = 3.3 V

Register Configuration

• Set Pass Mode: bit 2 of register 0x07 should be 1 to enter Pass Mode
• Set Torch Mode: bit 3 and 2 of register 0 × 01 should be 10 to enter Torch Mode
• Set LED current: for each channel bit 6~0 of register 0 × 06 should be 0010 1100 to set 125 mA for each channel
• Enable LED1 + LED2: bit 1 and 0 of register 0 × 01 should be 11 to turn on LED1 and LED2
• Wait for 2s or other expected delay time
• Disable LED1 + LED2: bit 1 and 0 of register 0 × 01 should be 00 to turn off LED and LED2

Figure 2-4 and Figure 2-5 shows the test results.

Summary

• Rising time is 2.4 μs from 0 to 500 mA
• After 20 μs, the output current becomes stable

Summary

• Keep torch time for 20s
• V_dropout (Vin-Vled) is about 350 mV, and this value is reasonable since the Vhr is 270 mV@typ and PFET conduction drop is 0.5 A*86 mOhm = 43 mV