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Contents

README

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LM3424QMHX

Texas Instruments · LED Drivers · HTSSOP-20-EP

LM3424QMHX from Texas Instruments, in a HTSSOP-20-EP. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 VIN power_in Input voltage pin; bypass with a 100 nF capacitor to GND as close to the device as possible.
2 EN input Enable pin; connect to more than 2.4 V to enable the device or to less than 0.8 V for low-power shutdown.
3 COMP input Compensation pin; connect a capacitor to GND to compensate the control loop.
4 CSH input Current sense high; connect a resistor to GND to set the signal current, which can also be used for analog dimming.
5 RT input Resistor timing; connect a resistor to GND to set the switching frequency, which can also be synchronized to an external clock.
6 nDIM input Dimming input and under-voltage protection; accepts a PWM dimming signal and/or a resistor divider from VIN to program input undervoltage lockout.
7 SS input Soft-start; connect a capacitor to GND to extend start-up time.
8 TGAIN input Temperature foldback gain; connect a resistor to GND to set the foldback slope.
9 TSENSE input Temperature sense input; connect a resistor/thermistor divider from VS to sense temperature.
10 TREF input Temperature foldback reference; connect a resistor divider from VS to set the foldback reference voltage.
11 VS power_in 2.45 V voltage reference for the temperature foldback circuit and other external circuitry.
12 OVP input Over-voltage protection; connect a resistor divider from VO to program the output over-voltage lockout.
13 DDRV output Dimming gate drive output; connect to the gate of the dimming MOSFET.
14 GND power_in Ground; connect to DAP to provide proper system GND.
15 GATE output Main gate drive output; connect to the gate of the main switching MOSFET.
16 VCC power_in Internal regulator output; bypass with a 2.2 µF to 3.3 µF ceramic capacitor to GND.
17 IS input Main switch current sense; connect to the drain of the main N-channel MOSFET for RDS-ON sensing or to a sense resistor in its source.
18 SLOPE input Slope compensation; connect a resistor to GND to set the slope of the additional ramp.
19 HSN input LED current sense negative; connect through a series resistor to the negative side of the LED current sense resistor.
20 HSP input LED current sense positive; connect through a series resistor to the positive side of the LED current sense resistor.
21 DAP passive Exposed pad (from the footprint; not named in the datasheet pin table).

Key specifications

Parameter Value
Manufacturer Texas Instruments
Package HTSSOP-20-EP
Category Nixie Tube Driver/LED Driver
Pins 21

CAD (KiCad official)

  • Symbol: LM3424QMHX
  • Footprint: Package_SO:TSSOP-20-1EP_4.4x6.5mm_P0.65mm_EP2.15x3.35mm
  • 3D model: HTSSOP-20-EP, generated from the KiCad footprint (body from the F.Fab outline, terminals on the pads, 1.2 mm nominal TSSOP height). Neither the vendor nor KiCad ships a 3D model for this package, so the dimensions are nominal, not the manufacturer's CAD (STEP)
  • 3D model files: lm3424qmhx-etched.step / lm3424qmhx-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); lm3424qmhx.step / lm3424qmhx.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (69 pp, sha256 d97444a162985e8c, retrieved 2026-10-08, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF