LED171596ARSLR datasheet(12/153 Pages) TI1

12 / 153 page

LED171596A

SNVSAY2 – OCTOBER 2017

www.ti.com

Submit Documentation Feedback

7 Detailed Description

7.1 Overview

The LED171596A is a LED driver that can individually control up to 96 LEDs. To control the 96 LEDs in a 4 × 24

matrix the device uses four high-side PMOS switches and 24 low-side programmable current sinks. Each of the

low-side current sinks has independent 9-bit duty cycle and 8-bit current control. The individually duty and current

values can be controlled through the SPI or I2C-compatible interfaces.

The four high-side switches allow the LED171596A 15 mA (ILED_MAX /4).

The individual LED brightness is internally multiplied with a global brightness register value. This allows the

control of all the LEDs at once with a single master brightness register or PWM input signal. This master

brightness also passes through a brightness sloper function to create optically smooth brightness transitions

without the need for multiple register writes.

Device control interface features:

•

EN is an enable input for LED171596A

•

INT is an open-drain interrupt output (indicating fault condition detection or sloper completion, for example)

•

IFSEL_LATCH is a dual function pin which is used for selecting between I2C-compatible and SPI after rising

edge of EN pin then can be used to latch register changes.

•

–

For interface selection the IFSEL pin status is checked after rising edge of EN pin. Note: IFSEL must be

static for tIFSEL_HOLD max time following EN rising edge.

–

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

–

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

–

An optional PWM input is available at SS/PWM when I2C is selected.

–

When I2C is selected, the ADDR pin is used to select between three alternate I2C slave addresses.

–

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

–

LATCH occurs on the rising edge. Minimum latch pulse length is tLATCH ns.

–

Alternatively a LATCH register bit can be used instead of pin control. Wait for latch_busy to be cleared

in STATUS register before writing to SRAM when using LATCH register bit.

•

ISET pin to set master LED current level for all LEDs.

Protection features of the LED171596A device include:

•

Open-LED and shorted-LED detections

–

When detected (unless masked), the INT pin goes low, and status registers show that LEDs are OPEN or

SHORT. Faulty LEDs can then be disabled via register bits, and fault status can be cleared.

•

Thermal shutdown in case of die overtemperature

LED171596ARSLR Datasheet(PDF) 12 Page - Texas Instruments

LED171596ARSLR Datasheet(HTML) 12 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL