main
Ray Publish 0.1.0 930d4ad 10d ago

LT3845AEFE#PBF

Analog Devices · DC-DC Converters · TSSOP-16-EP

LT3845AEFE#PBF from Analog Devices, in a TSSOP-16-EP. 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 Main supply pin, to be decoupled to SGND with a low ESR capacitor of at least 0.1µF located close to the pin; absolute maximum VIN is 65V and the operating range is 4V to 60V.
2 SHDN input Precision enable pin with a 1.35V rising threshold and 120mV hysteresis for UVLO; pulling it below 0.7V enters low-current shutdown, the pin is clamped to 6V, and its voltage rating is 5V with 1mA maximum pin current.
3 CSS passive Soft-start capacitor pin, where CSS = 2µA(tSS/1.231V) sets the output voltage slew rate; leave unconnected when soft-start is not used, and the voltage rating is 5V.
4 BURST_EN input Burst Mode enable pin where below 0.5V enables Burst Mode and reverse-current inhibit, above 0.5V disables Burst Mode, and reverse-current inhibit is disabled above 2.5V; the pin is rated 24V.
5 VFB input Output voltage feedback input connected to the supply output through a resistive divider, regulating at 1.231V, with a voltage rating of 5V.
6 VC passive Error amplifier output that sets the peak switch current and must not be pulled low by a low impedance source; if externally manipulated it must be driven through a 1kΩ series resistance, and the voltage rating is 5V.
7 SYNC input External clock input for oscillator synchronization, with RSET set so the internal oscillator runs 10% to 25% below the external clock within a 100kHz to 600kHz sync range; connect to SGND if unused, and the voltage rating is 5V.
8 fSET passive Oscillator frequency programming pin set by external resistor RSET, which is required even when an external sync clock is supplied; the programmable range is 100kHz to 500kHz.
9 SENSE- input Negative input of the current sense amplifier, connected to the VOUT side of the sense resistor in step-down applications; the pin is rated 40V and the differential sense voltage is limited to ±1V.
10 SENSE+ input Positive input of the current sense amplifier, connected to the inductor side of the sense resistor in step-down applications; the pin is rated 40V.
11 PGND power_in High-current ground reference for the internal low-side switch driver and VCC regulator, to be connected directly to the negative terminal of the VCC decoupling capacitor.
12 BG output Gate drive for the bottom N-channel MOSFET, to be routed with a short and wide trace (typically 0.02 in) to minimize inductance.
13 VCC power_out Internal bias supply decoupling node that requires a low ESR ceramic capacitor of 1µF or greater to PGND; the absolute maximum rating is 24V.
14 SW passive Reference for the VBOOST supply and high-current return for the bootstrapped switch; the switch voltage rating is 65V to -2V.
15 TG output Bootstrapped gate drive for the top N-channel MOSFET, to be routed with a short and wide trace (typically 0.02 in) to minimize inductance.
16 BOOST power_out Bootstrap supply for the gate drive, connected to a low ESR ceramic boost capacitor referenced to SW (0.1µF is typical); the maximum voltage seen is VIN + VCC, the BOOST-to-SW differential is limited to 24V, and the absolute maximum is 80V.
17 SGND power_in Exposed pad internally connected to the SGND low noise ground reference, which should be connected to the -VOUT side of the output capacitors and soldered to the PCB ground for thermal performance.

Key specifications

Parameter Value
Manufacturer Analog Devices
Package TSSOP-16-EP
Category Power Management ICs
Pins 17

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 supply voltage (VIN) VIN 65 V 2
Switch voltage (SW) SW -2 65 V Note 8: -2 V is a transient condition 2
SENSE+ and SENSE- voltages 40 V 2
Differential sense voltage -1 1 V SENSE+ to SENSE- 2
SYNC, VC, VFB, CSS and SHDN voltages 5 V 2
SHDN pin currents 1 mA 2
Operating junction temperature range (LT3845AE) TJ -40 125 °C LT3845AE (Note 3) 2
Storage temperature -65 150 °C 2
Lead temperature (soldering) 300 °C Soldering, 10 sec 2
Maximum junction temperature TJMAX 125 °C 2
Junction-to-ambient thermal resistance θJA 40 °C/W 2
Junction-to-case thermal resistance θJC 10 °C/W 2
VIN operating voltage range VIN 4 60 V 3
VIN minimum start voltage 7.5 V 3
VIN UVLO threshold (falling) 3.6 3.8 V 3
VIN UVLO threshold hysteresis 670 mV 3
VIN Burst Mode current 20 µA VBURST_EN = 0V, VFB = 1.35V 3
VIN shutdown current 9 15 µA VSHDN = 0V 3
BOOST operating voltage range VBOOST, VSW 5 V 3
BOOST supply current 1.4 mA Note 6 3
BOOST Burst Mode current 0.1 µA VBURST_EN = 0V 3
BOOST shutdown current 0.1 µA VSHDN = 0V 3
VCC operating voltage range VCC 8 V Note 5 3
VCC supply current 3.7 mA Note 6 3
VCC Burst Mode current 100 µA VBURST_EN = 0V 3
VCC shutdown current 20 µA VSHDN = 0V 3
Error amp reference voltage (full temperature range) 1.215 1.231 1.245 V Measured at VFB pin; l = full operating temperature range 3
Error amp reference voltage (TA = 25°C) 1.224 1.231 1.238 V TA = 25°C; measured at VFB pin 3
VFB pin input current IVFB 25 nA VFB = 1.231V 3
SHDN enable threshold (rising) 1.3 1.35 1.4 V l = full operating temperature range 3
SHDN threshold hysteresis 120 mV 3
Sense pins common mode range VSENSE+, VSENSE- 0 36 V 3
Current limit sense voltage VSENSE+, VSENSE- 90 100 115 mV VBURST_EN = VCC 3
Reverse protect sense voltage VSENSE+, VSENSE- -100 mV VBURST_EN = VCC 3
Reverse current inhibit offset 10 mV VBURST_EN = 0V or VBURST_EN = VFB 3
Input current (ISENSE+ + ISENSE-) 800 µA VSENSE(CM) = 0V 3
Input current (ISENSE+ + ISENSE-) -20 µA VSENSE(CM) = 2V 3
Input current (ISENSE+ + ISENSE-) -300 µA VSENSE(CM) > 4V 3
Operating frequency 270 300 330 kHz l = full operating temperature range 3
Minimum programmable frequency 100 kHz l = full operating temperature range 3
Maximum programmable frequency 500 kHz l = full operating temperature range 3
External sync frequency range 100 600 kHz l = full operating temperature range 3
SYNC input resistance 40 kΩ 3
SYNC voltage threshold 1.4 2 V l = full operating temperature range 3
Soft-start capacitor control current 2 µA 3
Error amp transconductance 270 340 410 µS l = full operating temperature range 3
Error amp DC voltage gain 62 dB 3
Error amp sink/source current -30 30 µA 3
TG, BG drive on voltage 9.8 V CLOAD = 3300pF; Note 7 4
TG, BG drive off voltage 0.1 V CLOAD = 3300pF 4
TG, BG drive rise/fall time 50 ns 10% to 90% or 90% to 10%, CLOAD = 3300pF 4
Minimum TG off time 350 650 ns l = full operating temperature range 4
Minimum TG on time 250 400 ns l = full operating temperature range 4
Gate drive nonoverlap time (TG fall to BG rise) 200 ns 4
Gate drive nonoverlap time (BG fall to TG rise) 150 ns 4

CAD (KiCad official)

  • Symbol: LT3845AEFE#PBF
  • Footprint: Package_SO:TSSOP-16-1EP_4.4x5mm_P0.65mm
  • 3D model: TSSOP-16-EP (KiCad packages3D, STEP)
  • 3D model files: lt3845aefe-pbf-etched.step / lt3845aefe-pbf-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); lt3845aefe-pbf.step / lt3845aefe-pbf.glb are the bare package body.

Provenance

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

  • Datasheet: Analog Devices datasheet (26 pp, sha256 6a4adebeb2ba3740, retrieved 2026-10-29, 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