# LT3502EMS#TRPBF

**Analog Devices** · DC-DC Converters · MSOP-10

LT3502EMS#TRPBF from Analog Devices, in a MSOP-10. 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 | SW | output | SW is the output of the internal power switch and connects to the inductor, catch diode and boost capacitor. |
| 2 | BOOST | passive | BOOST supplies a drive voltage higher than the input to the internal NPN power switch, with a boost capacitor connected from this pin to SW. |
| 3 | NC | unconnected | No internal connection. |
| 4 | DA | input | DA is the catch diode D1 anode connection and provides frequency foldback in extreme situations. |
| 5 | GND | power_in | Ground pin for the regulator. |
| 6 | SHDN | input | SHDN puts the part in shutdown when tied to ground, needs 2V or more for normal operation, must not exceed VIN, and provides soft-start and frequency foldback through R3 and C4. |
| 7 | FB | input | FB regulates to 0.8V; the output is set by VOUT = 0.8 (1 + R1/R2) with a recommended R2 of 10k. |
| 8 | BD | power_in | BD supplies current to the internal boost Schottky diode. |
| 9 | NC | unconnected | No internal connection. |
| 10 | VIN | power_in | VIN supplies current to the internal regulator and internal power switch and must be locally bypassed. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Analog Devices |
| Package | MSOP-10 |
| Category | Power Management ICs |
| Pins | 10 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Feedback Voltage (MS10, full temperature range) |  | 0.78 | 0.8 | 0.816 | V | MS10 package, l = full operating temperature range | 3 |
| Undervoltage Lockout |  | 2.6 | 2.8 | 3 | V |  | 3 |
| Quiescent Current at Shutdown |  |  | 0.5 | 2 | µA | VSHDN = 0V | 3 |
| Quiescent Current Not Switching |  |  | 1.5 | 2 | mA |  | 3 |
| Reference Voltage Line Regulation |  |  | 0.005 |  | %/V |  | 3 |
| FB Pin Bias Current |  |  | 15 | 50 | nA | l = full operating temperature range; Note 5 (current flows out of pin) | 3 |
| Switching Frequency (LT3502) |  | 0.9 | 1.1 | 1.3 | MHz | IDA < 500mA (LT3502), l | 3 |
| Switching Frequency (LT3502) |  | 0.8 | 1.1 | 1.4 | MHz | IDA < 500mA (LT3502), l | 3 |
| Maximum Duty Cycle (LT3502) |  |  | 80 | 90 | % | 100mA Load (LT3502) | 3 |
| Switch VCESAT | VCESAT |  |  | 450 | mV | ISW = 500mA | 3 |
| Switch Current Limit |  | 0.75 | 0.9 | 1.1 | A | Note 3 | 3 |
| Switch Active Current |  |  | 95 | 130 | µA | SW = 10V (Note 4) | 3 |
| Switch Active Current |  |  | 8 | 30 | µA | SW = 0V (Note 5) | 3 |
| BOOST Pin Current |  |  | 10 | 13 | mA | ISW = 500mA | 3 |
| Minimum BOOST Voltage Above Switch |  |  | 1.9 | 2.2 | V | ISW = 500mA | 3 |
| BOOST Schottky Forward Drop |  |  | 0.8 | 1 | V | IOUT = 100mA | 3 |
| DA Pin Current to Stop OSC |  |  | 500 | 650 | mA |  | 3 |
| SHDN Bias Current |  |  | 55 | 80 | µA | VSHDN = 5V | 3 |
| SHDN Bias Current |  |  |  | 1 | µA | VSHDN = 0V | 3 |
| SHDN Input Voltage High |  | 2 |  |  | V |  | 3 |
| SHDN Input Voltage Low |  |  |  | 0.3 | V |  | 3 |
| Input Voltage (VIN) | VIN |  |  | 40 | V |  | 2 |
| BOOST Voltage |  |  |  | 50 | V |  | 2 |
| BOOST Pin Above SW Pin |  |  |  | 7 | V |  | 2 |
| FB Voltage |  |  |  | 6 | V |  | 2 |
| SHDN Voltage |  |  |  | 40 | V |  | 2 |
| BD Voltage |  |  |  | 7 | V |  | 2 |
| Storage Temperature Range |  | -65 |  | 150 | °C |  | 2 |
| Operating Junction Temperature Range |  | -40 |  | 125 | °C | LT3502E, Note 2 | 2 |
| Input Voltage Range | VIN | 3 |  | 40 | V | wide input voltage range | 1 |
| Thermal Resistance Junction to Ambient (MS package) | θJA |  | 110 |  | °C/W | 10-Lead Plastic MSOP | 2 |

## CAD (KiCad official)

- Symbol: `LT3502EMS#TRPBF`
- Footprint: `Package_SO:MSOP-10_3x3mm_P0.5mm`
- 3D model: MSOP-10 (KiCad packages3D, STEP)
- 3D model files: `lt3502ems-trpbf-etched.step` / `lt3502ems-trpbf-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lt3502ems-trpbf.step` / `lt3502ems-trpbf.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Analog Devices datasheet](https://www.analog.com/media/en/technical-documentation/data-sheets/3502fd.pdf) (24 pp, sha256 `ee1026fdeba3ecdd`, retrieved 2026-11-02, tier: manufacturer)
- **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](docs/lt3502ems-trpbf-datasheet.pdf)