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lm3478mmx
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Texas Instruments AC-DC Controllers and Regulators, VSSOP-8-0.65mm. Datasheet-verified pinout, KiCad symbol/footprint/3D.
3D Model
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README
markdownLM3478MMX
Texas Instruments · AC-DC Controllers and Regulators · VSSOP-8-0.65mm
LM3478MMX from Texas Instruments, in a VSSOP-8-0.65mm. 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 | ISEN | input | Current sense input pin. The voltage generated across an external sense resistor (RSEN) in series with the source of the external N-channel MOSFET is fed into this pin for cycle-by-cycle current-mode control and current limiting. Absolute maximum pin voltage is 500 mV. |
| 2 | COMP | output | Compensation pin. A series resistor-capacitor network connected from this pin to AGND provides frequency compensation for the current-mode control loop. This pin is the output of the internal transconductance error amplifier. |
| 3 | FB | input | Feedback pin. Inverting input of the internal error amplifier; the output voltage should be adjusted using an external resistor divider to provide 1.26 V (nominal internal reference) at this pin. Absolute max: -0.4 V to 7 V. |
| 4 | AGND | power_in | Analog ground pin. Reference for the internal reference, error amplifier, and other small-signal circuitry. Should be tied to PGND at a single point (typically at the input capacitor return) to avoid ground loop noise. |
| 5 | PGND | power_in | Power ground pin. Return path for the high-current internal MOSFET gate driver (DR pin). Should be routed with a low-impedance connection back to the source of the external MOSFET / sense resistor. |
| 6 | DR | output | Drive pin. Output of the internal push-pull gate driver (1-A peak current capability) that drives the gate of the external low-side N-channel MOSFET. Pin voltage range is -0.4 V to 8 V (internally clamped for gate protection). |
| 7 | FA/SD | input | Frequency-adjust and shutdown pin. A resistor from this pin to AGND sets the internal oscillator frequency between 100 kHz and 1 MHz. Driving this pin high for longer than 30 µs shuts the device down, reducing supply current to less than 10 µA. Absolute max: -0.4 V to 7 V. |
| 8 | VIN | power_in | Power supply input pin. Provides bias to the internal control circuitry and the gate driver. Recommended operating range 2.97 V to 40 V; absolute maximum 45 V. Should be bypassed with a local ceramic capacitor to PGND. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | VSSOP-8-0.65mm |
| Category | PMIC |
| Pins | 8 |
Ordering variants
LM3478MMXLM3478MMXMM/NOPBLM3478MMX/NOPBLM3478MMXMLM3478MMXM/NOPB
CAD (KiCad official)
- Symbol:
LM3478MMX - Footprint:
Package_SO:VSSOP-8_2.3x2mm_P0.5mm - 3D model: VSSOP-8-0.65mm (KiCad packages3D, STEP)
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Texas Instruments datasheet (None pp, sha256
2135239904e04d87, retrieved 2026-08-17, tier: manufacturer) - 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).
Symbol & Footprint
Schematic Symbol
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PCB Footprint
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Datasheet
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