TLC5917QDRQ1

TLC5917QDRQ1 is Texas Instruments’ 7-channel constant-current LED sink driver with a simple serial interface. It provides seven low-side current sinks to drive LEDs or LED strings, while the LED anodes are tied to a higher supply. Each channel’s current is programmable via an external IREF resistor; PWM/dimming and overall brightness are controlled through a built-in grayscale/power-down scheme.
Key points
- 7 constant-current sink outputs; open-drain style
- Programmable per-channel current via IREF
- Serial (SPI-like) control interface: data, clock, latch (plus reset/BLANK as needed)
- Built-in dimming/ PWM functionality for smooth brightness control
- Low-pin-count, suitable for displays, backlights, indicators, and LED matrices
- Package: TLC5917QDRQ1 in a QFN (QDRQ1) package
Typical use
- Tie LED anodes to a suitable positive supply; connect cathodes to the TLC outputs
- Use the serial interface to set current and brightness
- Can cascade or multiplex across multiple devices as needed
For exact electrical specs (VDD range, IREF ranges, timing, and current limits), consult the TLC5917QDRQ1 datasheet.

TLC5917QDRQ1 comes in a QFN-28 (leadless) package (VQFN-28).

- Pin count: 28 pins (QFN package, TLC5917QDRQ1)
- Function: 8-channel constant-current LED sink driver with I2C-compatible control; each channel sinks LED current, with programmable current via IREF and overall dim/blanking control.

- Manufacturer: Texas Instruments (TI).
- What kind of company: An American multinational semiconductor company that designs and manufactures analog, mixed-signal, and digital integrated circuits for a wide range of applications.

Suitable for LED display backlighting and indicator applications needing constant-current sink control. Common uses: driving LED dot-matrix and 7-segment displays, LCD backlighting and keypad lighting, automotive dashboards/instrument clusters and status indicators, signage and architectural lighting, and general LED indicators in consumer/industrial equipment. It provides multiple constant-current sinks with open-load protection and is automotive-qualified (Q1) for harsh environments.

Direct equivalents (16-channel constant-current LED sink drivers):
- TI TLC5940 (16-channel CC LED sink, SPI-like)
- NXP PCA9955 / PCA9956B (16-channel CC LED sink, I2C)
- Macroblock MBI5024 / MBI5026 (16-channel CC LED sink, serial interface)
Notes: exact current ranges, voltage, interface, and package/pinouts vary; verify specs and footprints before substitution.