SG3525AP013TR from STMicroelectronics, in a SOIC-16. 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	INV. INPUT	input	Inverting input of the internal error amplifier. Common-mode input range includes the 5.1 V reference so external divider resistors are not required. Vos typ 0.5 mV, Ib typ 1 µA.
2	N.I. INPUT	input	Non-inverting input of the internal error amplifier. Typically tied to the VREF (pin 16) divider providing the regulation setpoint. CMR typ 75 dB.
3	SYNC	bidirectional	Oscillator sync terminal. Bidirectional: allows multiple SG3525A units to be slaved together or the device to be synchronized to an external system clock. Sync threshold typ 2 V, sync input current typ 1 mA at 3.5 V.
4	OSC. OUTPUT	output	Buffered oscillator clock output. Provides a system clock signal (amplitude typ 3.5 V) that can drive external logic or additional SG3525A devices.
5	CT	passive	Oscillator timing capacitor terminal. Connect timing capacitor (0.001 µF to 0.1 µF) from CT to ground. With RT sets the oscillator frequency (100 Hz-400 kHz operating range). Charge current limit 5 mA.
6	RT	passive	Oscillator timing resistor terminal. Connect timing resistor (2 kΩ to 150 kΩ) from RT to ground. Together with CT sets the oscillator frequency per f ≈ 1/(CT(0.7·RT + 3·RD)).
7	DISCHARGE	passive	Dead-time / discharge terminal. A resistor (RD, 0-500 Ω) placed between RT (pin 6) and DISCHARGE (pin 7) sets the timing-capacitor discharge current, giving programmable dead-time between the two outputs.
8	SOFT-START	passive	Soft-start capacitor terminal. An internal ~50 µA current source charges the external capacitor to progressively enable the PWM after start-up. Also discharged during shutdown for soft recycle.
9	COMP	output	Error-amplifier output / PWM comparator input (compensation node). Frequency-compensation network is tied here. Output high ≥3.8 V, output low ≤0.5 V; DC open-loop gain typ 75 dB.
10	SHUTDOWN	input	Pulse-by-pulse shutdown input. Threshold typ 0.8 V (0.6-1.0 V). When asserted (>threshold, VSS = 2.5 V typical drive) the PWM latch immediately turns both outputs off and discharges the soft-start capacitor. Shutdown delay typ 0.2 µs.
11	OUTPUT A	output	Totem-pole PWM driver output A. Alternates with OUTPUT B at half the oscillator frequency. Capable of sourcing/sinking >200 mA (400 mA peak). Rise/fall typ 100/50 ns into 1 nF.
12	GROUND	power_in	Signal and power ground reference for all internal circuitry.
13	VC	power_in	Collector (driver) supply for the totem-pole output stages. Operating range 4.5 V to 35 V (absolute max 40 V). Bypass locally with a low-ESR capacitor.
14	OUTPUT B	output	Totem-pole PWM driver output B, complementary to OUTPUT A with programmable dead-time between them. Source/sink capability >200 mA (400 mA peak).
15	+VI	power_in	Main IC supply voltage. Operating range 8 V to 35 V (absolute max 40 V). Undervoltage lockout keeps outputs off until Vcomp and Vss thresholds (6-8 V, typ 7 V) are exceeded, with ~500 mV hysteresis. Standby current typ 14 mA.
16	VREF	power_out	Trimmed 5.1 V ±1 % reference output (5.05-5.15 V at Tj=25 °C for SG2525A; 5.0-5.2 V for SG3525A). Short-circuit current typ 80 mA; load capability up to 20 mA. Bypass with 0.1 µF to ground.

Key specifications

Parameter	Value
Manufacturer	STMicroelectronics
Package	SOIC-16
Category	PMIC
Pins	16

Ordering variants

Same part, different packaging or reel option.

SG3525AP013TRSG2525AP
SG3525AP013TR
SG3525AP013TRSG2525AN
SG3525AN

CAD (KiCad official)

Symbol: SG3525AP013TR
Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
3D model: SOIC-16 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`sg3525ap013tr.step`	217 KB	You want the bare part, or you mark your own boards.
`sg3525ap013tr-etched.step`	3.4 MB	You want the part with `SG3525AP013TR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 813 faces against 267 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

Datasheet: STMicroelectronics datasheet (12 pp, sha256 249b8b0c18c356d5, 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