# LT3686IDD#PBF

**Analog Devices** · DC-DC Converters · DFN-10-EP(3x3)

LT3686IDD#PBF from Analog Devices, in a DFN-10-EP(3x3). 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 | The VIN pin supplies current to the internal regulator and internal power switch and must be locally bypassed; the input range is 3.6V to 37V. |
| 2 | BD | passive | The BD pin supplies current to the internal Boost Schottky diode, should be tied to the output whenever possible, and regulates an active load when MODE is above 0.8V. |
| 3 | FB | input | The feedback pin regulates to 0.8V, with the output set by VOUT = 0.8(1 + R1/R2) and a recommended R2 of 10k. |
| 4 | SS | input | The soft-start and tracking pin is charged by an internal 2µA source tied to a 2.5V reference, and feedback stops tracking at 0.8V; the pin should float if soft-start is not used. |
| 5 | RT | input | The RT pin programs the oscillator frequency through a resistor selected from Table 1 in the applications section. |
| 6 | EN/UVLO | input | The EN/UVLO pin starts up the device, shuts it down when pulled below 0.4V, provides a 1.27V UVLO threshold, and must not be driven above VIN. |
| 7 | MODE | input | The MODE pin selects the BD active load, which is enabled when MODE is above 0.8V and disabled when tied to GND. |
| 8 | BOOST | input | The BOOST pin provides a drive voltage higher than the input voltage to the internal NPN power switch. |
| 9 | DA | passive | The DA pin is the connection for the catch diode (D1) anode. |
| 10 | SW | output | The SW pin is the output of the internal power switch and connects to the inductor, catch diode and boost capacitor. |
| 11 | GND | power_in | The exposed pad GND pin is the only ground connection for the device and must be soldered to a large copper area to reduce thermal resistance. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Analog Devices |
| Package | DFN-10-EP(3x3) |
| Category | Power Management ICs |
| Pins | 11 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Quiescent Current at Shutdown | IQ |  | 0.1 | 1 | µA | VEN/UVLO < 0.4V | 3 |
| Quiescent Current at Shutdown | IQ |  | 10 | 15 | µA | VEN/UVLO = 1V | 3 |
| Quiescent Current Not Switching | IQ |  | 1.1 | 1.3 | mA | Not Switching, MODE ≤ 0.4V | 3 |
| Quiescent Current Not Switching | IQ |  | 1.2 | 1.4 | mA | Not Switching, MODE ≥ 0.8V | 3 |
| Internal Undervoltage Lockout |  |  | 3.4 | 3.6 | V |  | 3 |
| Overvoltage Lockout |  | 37 | 38 | 39 | V | l (full operating temperature range) | 3 |
| Feedback Voltage | VFB | 0.79 | 0.8 | 0.81 | V | l (full operating temperature range) | 3 |
| Feedback Voltage | VFB | 0.785 | 0.8 | 0.815 | V | l (full operating temperature range) | 3 |
| FB Pin Bias Current | IFB |  | 20 | 100 | nA |  | 3 |
| Minimum On Time |  |  | 100 | 110 | ns |  | 3 |
| Minimum Off Time |  |  | 150 | 200 | ns |  | 3 |
| Switch Current Limit |  | 1.9 | 2.3 | 2.6 | A | Note 3 | 3 |
| Switch Current Limit |  | 1.85 | 2.3 | 2.65 | A | l (full operating temperature range), Note 3 | 3 |
| Switch Active Current |  |  | 400 | 600 | µA | SW = 10V (Note 4) | 3 |
| Switch Active Current |  |  | 20 | 30 | µA | SW = 0V (Note 5) | 3 |
| Minimum Boost Voltage Above Switch |  |  | 2.2 | 2.4 | V | ISW = 1.2A | 3 |
| Max BD Pin Active Load Current |  |  | 30 | 40 | mA | MODE > 0.8V, BD < 5.2V | 3 |
| BD Pin Active Load Disable Threshold |  |  | 5.2 | 6.5 | V | l (full operating temperature range) | 3 |
| DA Pin Current to Stop OSC |  |  | 1.2 | 1.7 | A | l (full operating temperature range) | 3 |
| MODE High |  | 0.8 |  |  | V | l (full operating temperature range) | 3 |
| MODE Low |  |  |  | 0.4 | V | l (full operating temperature range) | 3 |
| SS Source Current | ISS | 1.3 | 2 | 2.7 | µA | VSS = 1V | 3 |
| EN/UVLO Threshold to Turn Off |  | 1.22 | 1.27 | 1.32 | V | l (full operating temperature range) | 3 |
| EN/UVLO Hysteresis Current |  | 1.8 | 2.4 | 3 | µA |  | 3 |
| BOOST Pin Above SW Pin | VBOOST-SW |  |  | 25 | V |  | 2 |
| FB Voltage | VFB |  |  | 6 | V |  | 2 |
| BD Voltage | VBD |  |  | 25 | V |  | 2 |
| RT Voltage | VRT |  |  | 6 | V |  | 2 |
| SS Voltage | VSS |  |  | 2.5 | V |  | 2 |
| MODE Voltage | VMODE |  |  | 6 | V |  | 2 |
| Operating Junction Temperature Range | TJ | -40 |  | 125 | °C | LT3686I | 2 |
| Storage Temperature Range | TSTG | -65 |  | 150 | °C |  | 2 |
| Thermal Resistance Junction to Ambient | θJA |  | 43 |  | °C/W |  | 2 |

## CAD (KiCad official)

- Symbol: `LT3686IDD#PBF`
- Footprint: `Package_DFN_QFN:DFN-10-1EP_3x3mm_P0.5mm_EP1.55x2.48mm`
- 3D model: DFN-10-EP(3x3) (KiCad packages3D, STEP)
- 3D model files: `lt3686idd-pbf-etched.step` / `lt3686idd-pbf-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lt3686idd-pbf.step` / `lt3686idd-pbf.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/3686fc.pdf) (28 pp, sha256 `21c973cf91b5f4e3`, retrieved 2026-10-28, 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/lt3686idd-pbf-datasheet.pdf)