TI LED171596A 96個LED陣列敺動解決方案

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– If IFSEL is pulled low （0） the 4-wire SPI interface is selected （SCLK， MISO， MOSI， and SS）。

– 7-V Tolerant
– If IFSEL is pulled high （1） the 2-wire I2C-compatible interface is selected.

• Four Low Resistance High Side Series Switches
– An optional PWM input is available at SS/PWM when I2C is selected.

Protection features of the LED171596A device include：
The LED171596A is a LED driver that can individually control up to 96 LEDs. To control the 96 LEDs in a 4 × 24matrix the device uses four high-side PMOS switches and 24 low-side programmable current sinks. Each of thelow-side current sinks has independent 9-bit duty cycle and 8-bit current control. The individually duty and currentvalues can be controlled through the SPI or I2C-compatible interfaces.



LED171596A應用：






• Local Dimming LED Backlight Drivers







圖2,流鼻涕.LED171596A簡化電路圖
– Current Matching ±5%

1• 24 High-Precision Current Sinks
圖7.評估板LED171596A EVM電路圖（2）
• Thermal shutdown in case of die overtemperature.


– 60-mA Peak Current per Channel


圖5.評估板LED171596A EVM外形圖
– Independent 9-Bit Duty Cycle PWM and 8-BitLED Current Control
圖3.LED171596A典型應用電路圖
• Open-LED and shorted-LED detections
• Control Panel Illumination






圖6.評估板LED171596A EVM電路圖（1）

– Alternatively a LATCH register bit can be used instead of pin control. Wait for latch_busy to be clearedin STATUS register before writing to SRAM when using LATCH register bit.
圖4.LED171596A亮度通路圖





• INT is an open-drain interrupt output （indicating fault condition detection or sloper completion， for example）
– When detected （unless masked）， the INT pin goes low， and status registers show that LEDs are OPEN orSHORT. Faulty LEDs can then be disabled via register bits， and fault status can be cleared.




The individual LED brightness is internally multiplied with a global brightness register value. This allows thecontrol of all the LEDs at once with a single master brightness register or PWM input signal. This masterbrightness also passes through a brightness sloper function to create optically smooth brightness transitionswithout the need for multiple register writes.




– Open and Shorted LED Fault Detection
TI公司的LED171596A是用於RGB和白光LED的96個（24x4） LED陣列敺動器，具有單獨的通路控制，支持4個低電阻高邊開關和24個低邊電流沉，每路可提供多達15mA的連續電流，電流匹配度±5%，I2C，SPI和PWM亮度控制模式，具有擴展的保護功能如開路和短路LED故障檢測和熱關斷保護。主要用在控制面板炤明和侷部地區調光LED揹景光敺動器。本文介紹了LED171596A主要特性，功能框圖和應用電路，亮度通路圖以及評估板LED171596A EVM特性，電路圖，材料清單和PCB設計圖。


圖11,租印表機.評估板LED171596A EVM PCB設計圖（4）
– ISET Resistor to Set Global Current
LED171596A主要特性：




圖8.評估板LED171596A EVM PCB設計圖（1）

圖1.LED171596A功能框圖
– When I2C is selected， the ADDR pin is used to select between three alternate I2C slave addresses.



圖12.評估板LED171596A EVM PCB設計圖（5）

• Extensive Protection Features

– LATCH occurs on the rising edge. Minimum latch pulse length is tLATCH ns.
– 1.5-A Current-Rated PMOS

Device control interface features：

– Ghosting Cancellation
– In normal mode the pin functions as a LATCH signal to trigger updates of SRAM buffers.

• EN is an enable input for LED171596A

LED171596A 96-LED Matrix Driver for RGB and White LEDs.The LED171596A is a 96 channel matrix LED driverwith independent channel control， designed fordriving locally dimmed displays. The device sports 4low-resistance high side switches and 24 low side current sinks that can deliver up to 15 mA ofcontinuous current per channel. The driver has 9-bitduty cycle and 8-bit current control of each low-sideLED current sink.

圖10,縫雙眼皮推薦.評估板LED171596A EVM PCB設計圖（3）

– Thermal Shutdown Protection
– For interface selection the IFSEL pin status is checked after rising edge of EN pin. Note： IFSEL must bestatic for tIFSEL_HOLD max time following EN rising edge.







• I2C， SPI， and PWM Brightness Control Modes





• IFSEL_LATCH is a dual function pin which is used for selecting between I2C-compatible and SPI after risingedge of EN pin then can be used to latch register changes.

評估板LED171596A EVM
• ISET pin to set master LED current level for all LEDs.

圖9.評估板LED171596A EVM PCB設計圖（2）
評估板LED171596A EVM材料清單：


The four high-side switches allow the LED171596A to time multiplex four groups of 24 LEDs. Maximum peakcurrent is set with ISET （with 60 mA maximum）， but the maximum average current delivered to each LED is 15mA （ILED_MAX /4）。

Each current sink can be individually controlledthrough the I2C-compatible or SPI interface， but alsohas the capability to be controlled with a single valuethrough the global brightness control register. Thisglobal brightness control also passes through abrightness sloper function to create optically smoothbrightness transitions without the need for multipleregister writes.


The Texas Instruments LED171596A evaluation module （EVM） helps designers evaluate the operationand performance of the LED171596A 96-LED driver. The LED171596A is an LED matrix driver that canindividually control up to 96 LEDs. To control the 96 LEDs it uses four high-side PMOS switches and 24low-side programmable current sinks. The driver has 9-bit duty cycle and 8-bit current control of each lowside LED current sink. They can be individually controlled through the I2C-compatible or SPI interface.The EVM contains one LED171596A and one LEDARRAYEVM with 96 white LEDs.