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LD7838GR

Leadtrend Tech · LED Drivers · SOP-7

LD7838GR from Leadtrend Tech, in a SOP-7. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 ZCD input Quasi-resonance zero-current detector and programmable maximum ON-time input. Input threshold ~0.2V (with 0.1V hysteresis), clamped between ~-0.3V and ~4.7V. ZCD OVP trips at ~3.5V for output over-voltage protection.
2 COMP input Feedback/compensation pin. Connect a photo-coupler to close the control loop for regulation. Open-loop voltage ~5.0-5.8V; OLP trip ~4.6V; zero-ON-time burst threshold ~0.5V. Requires a 0.22-4.7uF filter capacitor.
3 CS input Current sense pin for the external MOSFET; pulse-by-pulse OCP threshold ~0.85V, secondary diode-short threshold ~1.2V. Includes ~425ns leading-edge blanking. Recommended R-C filter: 100-2k ohm and 100-680 pF.
4 GND power_in Device ground reference for all internal circuitry and the gate driver return.
5 OUT output Gate drive output for the external power MOSFET. CMOS totem-pole with ~125mA source / -500mA sink capability, clamped at ~13V for gate protection. Absolute range -0.3V to VCC+0.3V.
6 VCC power_in Controller supply pin. Operating range 9.5-27.5V; UVLO ON ~16V, UVLO OFF ~8V, VCC OVP ~28V, PDR ~7.5V, absolute max 30V. Requires 4.7-22uF bulk plus a 0.1-0.47uF SMD ceramic close to the pin.
8 HV power_in High-voltage startup pin (700V rated). Connect to the positive terminal of the main bulk cap to source ~1.8mA startup current until VCC reaches UVLO(on); then the internal HV current source is disabled to minimize standby loss. Also senses Brown-in/Brown-out (~90V DC in / hysteresis ~10V).

Key specifications

Parameter Value
Manufacturer Leadtrend Tech
Package SOP-7
Category LED-drv
Pins 7

Ordering variants

  • LD7838GR

CAD (KiCad official)

  • Symbol: LD7838GR
  • Footprint: Package_SO:SOIC-8-N7_3.9x4.9mm_P1.27mm
  • 3D model: SOP-7 (KiCad packages3D, STEP)

Provenance

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

  • Datasheet: Leadtrend Tech datasheet (None pp, sha256 1356d9883c089a39, retrieved 2026-08-17, tier: lcsc)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF

Symbol & Footprint

Schematic Symbol

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PCB Footprint

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