ZHCSHU7J August 2005 – March 2021 PCA9555
PRODUCTION DATA
- 1 特性
- 2 應用
- 3 說明
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
- 7 Parameter Measurement Information
- 8 Detailed Description
- 9 Application Information Disclaimer
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
封裝選項
機械數據 (封裝 | 引腳)
散熱焊盤機械數據 (封裝 | 引腳)
- RGE|24
訂購信息
9.1.1.2.1 Minimizing ICC When I/O Is Used To Control Led
When an I/O is used to control an LED, normally it is connected to VCC through a resistor as shown in Figure 9-1. Because the LED acts as a diode, when the LED is off, the I/O VIN is about 1.2 V less than VCC. The ΔICC parameter in Electrical Characteristics shows how ICC increases as VIN becomes lower than VCC. For battery-powered applications, it is essential that the voltage of I/O pins is greater than or equal to VCC when the LED is off to minimize current consumption.
Figure 9-2 shows a high-value resistor in parallel with the LED. Figure 9-3 shows VCC less than the LED supply voltage by at least 1.2 V. Both of these methods maintain the I/O VIN at or above VCC and prevent additional supply current consumption when the LED is off.
Figure 9-2 High-Value Resistor In Parallel With Led
Figure 9-3 Device Supplied By Lower Voltage