LP3943ISQEV/NOPB National Semiconductor, LP3943ISQEV/NOPB Datasheet
LP3943ISQEV/NOPB
Specifications of LP3943ISQEV/NOPB
*LP3943ISQEV/NOPB
LP3943ISQEV
Related parts for LP3943ISQEV/NOPB
LP3943ISQEV/NOPB Summary of contents
Page 1
... Maximum output sink current per pin and 200 mA per package. Any ports not used for controlling the LEDs can be used for general purpose input/output expansion. Typical Application Circuit © 2003 National Semiconductor Corporation Features n Internal power-on reset n Active low reset n Internal precision oscillator n Variable dim rates (from 6. 1.6s ...
Page 2
LP3943 Pin Out LP3943 Pin Description Pin # Name 1 LED0 2 LED1 3 LED2 4 LED3 5 LED4 6 LED5 7 LED6 8 LED7 9 GND 10 LED8 11 LED9 12 LED10 13 LED11 14 LED12 15 LED13 16 ...
Page 3
Architectural Block Diagram For Explanation of LP3943 Operation, Please Refer to “Theory of Operation” in Application Notes. 3 20079603 www.national.com ...
Page 4
... Absolute Maximum Ratings 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications A0, A1, A2, SCL, SDA, RST (Collectively called digital pins) Voltage on LED pins Junction Temperature Storage Temperature Power Dissipation (Note 3) Electrical Characteristics Unless otherwise noted ...
Page 5
Electrical Characteristics Unless otherwise noted 5.5V. Typical values and limits appearing in normal type apply for boldface type apply over the entire junction temperature range for operation, T Symbol Parameter INTERFACE (SCL ...
Page 6
Application Notes THEORY OF OPERATION The LP3943 takes incoming data from the baseband con- troller and feeds them into several registers that control the frequency and the duty cycle of the LEDs. Two prescaler registers and two PWM registers provide ...
Page 7
Application Notes (Continued write (SDA = “0” read (SDA = “1”) ack = acknowledge (SDA pulled LOW by either master or slave repeated start However READ function ...
Page 8
Application Notes (Continued) AUTO INCREMENT Auto increment is a special feature supported by the LP3943 to eliminate repeated chip and register addressing when data are to be written to or read from registers in sequential In the READ mode, when ...
Page 9
Application Notes (Continued) Address (Hex) Register Name 0x00 Input 1 0x01 Input 2 0x02 PSC0 0x03 PWM0 0x04 PSC1 0x05 PWM1 0x06 LS0 0x07 LS1 0x08 LS2 0x09 LS3 BINARY FOMAT FOR INPUT REGISTERS (READ ONLY) — ADDRESS 0x00 and ...
Page 10
Application Notes (Continued) Bit # 7 Default value 1 PWM1 register determines the duty cycle of DIM1. The LED outputs are LOW (LED on) when the count is less than the value in PWM1 and HIGH (LED off) when it ...
Page 11
Application Notes (Continued) Programming Example: Dim LEDs 25% duty cycle Dim LEDs 50% duty cycle Set LEDs 13, 14 and 15 off Step 1: Set PSC0 ...
Page 12
Application Notes (Continued) Pub Lcl genlevel=LP3943 Driving RGB LED As A Flash www.national.com LP3943 With 5V Booster 20079616 12 20079615 ...
Page 13
... BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...