component
SQ9912MST
Public Made by Adomby adom
Sequoia Microelectronics LED Drivers, SO-8. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
3D Model
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Symbol & Footprint
Schematic Symbol
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PCB Footprint
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Datasheet
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README
markdownSQ9912MST
Sequoia Microelectronics · LED Drivers · SO-8
SQ9912MST from Sequoia Microelectronics, in a SO-8. 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 | High-voltage input pin, specified for a DC input voltage of 15.0 V to 500 V, with an absolute maximum rating of -0.5 V to +520 V to GND. |
| 2 | CS | input | Senses the LED string current through the external source sense resistor, with a peak current sense threshold of 250 mV (225 mV to 275 mV) and an absolute rating of -0.3 V to (VDD + 0.3 V). |
| 3 | GND | power_in | Device ground; all voltages in the datasheet are referenced to this pin. |
| 4 | GATE | output | Drives the gate of the external power MOSFET, with a high output of VDD - 0.3 V minimum and a low output of 0.3 V maximum, and an absolute rating of -0.3 V to (VDD + 0.3 V). |
| 5 | PWM_D | input | Low-frequency PWM dimming input that also acts as the enable, with input low at 1.0 V maximum and input high at 2.4 V minimum, an internal 200 kΩ pull-down to GND, and an absolute rating of -0.3 V to (VDD - 0.3 V). |
| 6 | VDD | power_out | Internally regulated supply, 7.5 V nominal for SQ9912 and 10 V nominal for SQ9912A, which can supply up to 1 mA to external circuitry and has a maximum voltage of 13.5 V when an external voltage is applied. |
| 7 | OLP | input | Open-loop protection pin used to detect whether LED loading is present, with an internal 100 kΩ pull-up to VDD and an absolute rating of -0.3 V to (VDD - 0.3 V). |
| 8 | ROSC | passive | Oscillator control: a resistor from this pin to GND sets the PWM frequency per FOSC = 25000/(ROSC[kΩ] + 22) kHz, over a range of 25 kHz to 300 kHz. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Sequoia Microelectronics |
| Package | SO-8 |
| Category | LED Drivers |
| Pins | 8 |
Electrical characteristics
Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Input DC supply voltage range | VINDC | 15 | 500 | V | DC input voltage | 3 | |
| Internally regulated voltage (SQ9912) | VDD | 7 | 7.5 | 8 | V | VIN = 20 - 500V, lDD(ext)= 0, VDD pin Gate open | 3 |
| Maximal pin Vdd voltage | VDDmax | 13.5 | V | When an external voltage applied to pin Vdd | 3 | ||
| VDD current available for external circuitry | IDD(ext) | 1 | mA | VIN = 20-100V | 3 | ||
| VDD under voltage lockout threshold (SQ9912) | UVLO | 6.4 | 6.7 | 7 | V | Vin rising | 3 |
| Pin PWM_D input low voltage | VEN(lo) | 1 | V | VIN = 20-500V | 3 | ||
| Pin PWM_D input high voltage | VEN(hi) | 2.4 | V | VIN = 20-500V | 3 | ||
| Pin PWM_D pull-down resistance | REN | 150 | 200 | 250 | kΩ | VEN = 5V | 3 |
| Current sense pull-in threshold voltage | VCS(hi) | 225 | 250 | 275 | mV | @TA = -40°C to +85°C | 3 |
| GATE low output voltage | VGATE(lo) | 0 | 0.3 | V | IOUT = -10mA | 3 | |
| Oscillator frequency (ROSC = 1.00MΩ) | fOSC | 20 | 25 | 30 | kHz | ROSC = 1.00MΩ | 3 |
| Oscillator frequency (ROSC = 226kΩ) | fOSC | 80 | 100 | 120 | kHz | ROSC = 226kΩ | 3 |
| Maximum oscillator PWM duty cycle | DMAXhf | 100 | % | FPWMhf = 25kHz, at GATE, CS to GND. | 3 | ||
| Linear dimming pin voltage range | VLD | 0 | 250 | mV | @TA = <85°C, VIN = 20V | 3 | |
| Current sense blanking interval | TBLANK | 160 | 250 | 440 | ns | VCS = 0.5V | 3 |
| Delay from CS trip to GATE lo | tDELAY | 300 | ns | VIN = 20V, VLD = 0.15, VCS = 0 to 0.22V after TBLANK | 3 | ||
| GATE output rise time | tRISE | 30 | 50 | ns | CGATE = 500pF | 3 | |
| GATE output fall time | tFALL | 30 | 50 | ns | CGATE = 500pF | 3 | |
| Soft-start time | tSS | 300 | 400 | 500 | μS | From appearance of pulses at DRIVER pin to increase Duty Cycle more 50% | 3 |
| Input DC supply voltage range absolute limit VIN to GND | VIN | -0.5 | 520 | V | 2 | ||
| VDD(MAX) | VDD(MAX) | 13.5 | V | 2 | |||
| Continuous power dissipation, 8 Pin SO | 630 | mW | TA = 25C | 2 | |||
| Junction temperature range | TJ | 125 | C | 2 | |||
| Storage temperature range | TSTG | -65 | 150 | °C | 2 | ||
| Operating temperature range | TA | -40 | 85 | °C | 2 | ||
| Shut-down mode supply current (SQ9912) | IInsd | 0.5 | 1 | mA | Pin PWM_D to GND, VIN = 20V | 3 | |
| VDD under voltage lockout hysteresis (SQ9912) | ∆UVLO | 500 | mV | Vin falling | 3 | ||
| Thermal Shutdown | TSD | 150 | C | 3 | |||
| Thermal Shutdown Hysteresis | TSDH | 50 | C | 3 |
CAD (KiCad official)
- Symbol:
SQ9912MST - Footprint:
Package_SO:SOIC-8_3.9x4.9mm_P1.27mm - 3D model: SO-8 (KiCad packages3D, STEP)
- 3D model files:
sq9912mst-etched.step/sq9912mst-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);sq9912mst.step/sq9912mst.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Sequoia Microelectronics datasheet (11 pp, sha256
063addd0bd9803c3, retrieved 2026-10-19, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusclaude-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).