My Inquiry
My Account
Analog Devices Inc. LT3502AIMS#PBF
- Part No.:
- LT3502AIMS#PBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
LT3502AIMS#PBF.pdf
- Description:
- IC REG BUCK ADJ 500MA 10MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:433
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3502AIMS#PBF from Analog Devices (formerly Linear Technology) is a constant-frequency, current-mode PWM step-down DC/DC converter with an integrated 500mA bipolar NPN power switch, designed for 3V–40V input and fixed 3.3V or adjustable output regulation. It operates at 2.2MHz switching frequency, features 0.8V feedback reference, internal boost diode, and thermal protection in a 10-lead MSOP package. It is used in automotive infotainment power rails and industrial 24V distributed supplies.
For engineers reviewing the LT3502AIMS#PBF datasheet, LT3502AIMS#PBF pinout, LT3502AIMS#PBF application, or LT3502AIMS#PBF equivalent, key selection criteria include its 2.2MHz operation (AM-band avoidance), 0.8V FB threshold, DA-pin-based frequency foldback for short-circuit robustness, and MSOP-10 thermal performance (θJA = 110°C/W).
Technical Context
The LT3502AIMS#PBF implements current-mode control using an RS flip-flop–driven oscillator and peak-current sensing across the internal switch, with slope compensation to stabilize duty cycles >50%. Its VC node is servoed by an error amplifier referenced to 0.8V at FB and clamped by SHDN voltage during soft-start.
Frequency foldback is triggered by DA pin current exceeding 650mA (valley current limit), reducing switching frequency under overload or short-circuit conditions. The BOOST pin-driven via internal Schottky diode and external capacitor-supplies >2.2V above SW to fully saturate the NPN switch, enabling efficient operation up to 40V input.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | 2.2MHz - enables use of sub-10µH inductors and avoids AM radio band interference. |
| Max Output Current | 500mA - continuous load capability with thermal derating above 85°C ambient. |
| Input Voltage Range | 3V to 40V - supports 24V industrial buses and 12V/24V automotive batteries with cold-crank tolerance. |
| Feedback Reference | 0.8V ±13mV - sets output voltage via resistor divider; enables precise 3.3V, 5V, or custom regulation. |
| Shutdown Current | <2µA - minimizes battery drain in always-on systems such as telematics modules. |
| Current Limit Threshold | 0.75A to 1.1A (typ. 0.9A) - cycle-by-cycle peak switch current limit with temperature compensation. |
| Package Thermal Resistance | θJA = 110°C/W (MSOP-10) - requires exposed pad soldering for reliable 500mA operation at 125°C junction. |
Pinout & Package
LT3502AIMS#PBF is housed in a 10-lead plastic MSOP (MS package) with exposed pad (GND-connected), rated for –40°C to 125°C junction temperature. The package measures 3mm × 3mm × 1.1mm and requires soldering of Pin 5 (exposed pad) to PCB ground plane for thermal integrity.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (Pin 10) | Power input supply | Supplies internal regulator and switch; must be bypassed with ≥1µF X7R ceramic close to pin. |
| BD (Pin 8) | Boost diode anode connection | Connects to internal Schottky; ties to VIN or external bias for low-VOUT applications (<3V). |
| FB (Pin 7) | Feedback reference node | Servo point for 0.8V regulation; connects to resistor divider tap to set VOUT = 0.8(1 + R1/R2). |
| SHDN (Pin 6) | Enable/soft-start control | Active-high logic input; <0.3V = shutdown (<2µA IQ); ≥2V = active; RC ramp enables controlled start-up. |
| GND (Pin 5) | Power and signal ground | Common return for all circuits; exposed pad (Pin 5) must be soldered to PCB GND for thermal management. |
| DA (Pin 4) | Diode anode current monitor | Detects catch diode valley current; triggers frequency foldback when >650mA to limit fault energy. |
| BOOST (Pin 2) | Switch driver bootstrap supply | Driven by internal diode + external cap; must be ≥2.2V above SW for full NPN saturation and efficiency. |
| SW (Pin 1) | Switch node output | Connects to inductor, catch diode cathode, and BOOST capacitor; carries high di/dt pulsed current. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated boost diode | Eliminates external bootstrap diode, reducing BOM count and layout area in MSOP-10 footprint. |
| DA-pin frequency foldback | Reduces switching frequency under short-circuit to limit power dissipation and maintain safe junction temperature. |
| 2.2MHz fixed-frequency operation | Enables compact 6.8µH inductor and 10µF ceramic output capacitor for 3.3V/500mA designs. |
| 0.8V feedback reference | Allows accurate output setting with standard 1% resistors; R2 = 10kΩ recommended for minimal bias error. |
| Internal compensation | Removes need for external compensation network, simplifying design while maintaining stability across loads. |
Applications
| Automotive Infotainment Power | Industrial 24V Point-of-Load |
|---|---|
|
Use Scenario: Powering DSP, display controller, and audio codec in head unit with 12V battery input and 3.3V/500mA rail requirement. IC Role / Device Role / Timing Role: Primary buck regulator providing regulated 3.3V from noisy, wide-range automotive supply. Use Value: 2.2MHz operation avoids AM band interference; frequency foldback prevents thermal runaway during ESD-induced shorts. |
Use Scenario: Generating 5V/500mA from 24V factory automation bus for PLC I/O module logic supply. IC Role / Device Role / Timing Role: Compact, thermally robust step-down converter replacing discrete switcher solutions. Use Value: MSOP-10 package with exposed pad sustains 500mA at 85°C ambient without heatsink; 40V abs max rating handles 24V transients. |
| Wall Adapter Regulation | Distributed Telecom Supply |
|
Use Scenario: Regulating 12V wall adapter output to 3.3V for IoT gateway MCU and RF subsystem. IC Role / Device Role / Timing Role: High-efficiency, low-noise buck converter minimizing conducted EMI into sensitive wireless receivers. Use Value: Constant 2.2MHz frequency enables predictable filter design; internal compensation ensures stability with 10µF ceramic output cap. |
Use Scenario: Providing isolated 5V bias for optical transceiver modules in 48V telecom shelf systems. IC Role / Device Role / Timing Role: Non-isolated intermediate buck stage stepping 48V down to 5V before final isolated DC/DC. Use Value: 3V–40V input range accommodates brownout and surge conditions; <2µA shutdown current preserves standby battery life. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar step-down regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LT3502AEDC#PBF | Same IC die, but in 8-lead 2mm × 2mm DFN package (θJA = 102°C/W); identical electrical specs and pinout mapping. | Better thermal performance per mm²; preferred for space-constrained PCBs where thermal vias under DFN are feasible. | Select LT3502AEDC#PBF when board area is critical and thermal management via PCB vias is possible. |
| MP2307DN-LF-Z | 2.2MHz synchronous buck; 3.3V–28V input; 2A output; no DA-foldback; uses MOSFET switches instead of bipolar. | Higher current capability but lacks valley-current–based fault protection; less robust under sustained short-circuit. | Choose MP2307DN-LF-Z only if >500mA output and synchronous efficiency outweigh need for automotive-grade fault resilience. |
Compared with LT3502AEDC#PBF, the LT3502AIMS#PBF trades slightly higher θJA for easier hand-soldering and probing; versus MP2307DN-LF-Z, it offers superior short-circuit survival via DA-foldback but lower max current and bipolar switch losses.
Availability
LT3502AIMS#PBF is available at Aetrix Electronics and suitable for automotive infotainment, industrial 24V point-of-load, and telecom distributed supply applications requiring stable component supply, long-term lifecycle support, and AEC-Q200–compatible design-in assurance.
Supply support for LT3502AIMS#PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Analog Devices (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving precision instrumentation, industrial, automotive, and communications markets.
The LT3502/LT3502A product line was engineered for rugged, wide-input-voltage DC/DC conversion in noise-sensitive and thermally constrained environments-especially automotive and industrial systems demanding AM-band–free operation and short-circuit resilience.
FAQ
What is the switching frequency of the LT3502AIMS#PBF and why does it matter?
The LT3502AIMS#PBF operates at a fixed 2.2MHz switching frequency. This high frequency allows use of small inductors (e.g., 6.8µH) and ceramic capacitors (e.g., 10µF), minimizing solution size and avoiding interference with AM radio bands (530–1710kHz). It also enables faster transient response compared to lower-frequency buck regulators.
How does the DA pin on the LT3502AIMS#PBF improve reliability?
The DA pin on the LT3502AIMS#PBF monitors catch diode valley current and initiates frequency foldback when current exceeds ~650mA. This reduces switching frequency under overload or short-circuit conditions, limiting power dissipation and preventing thermal runaway-critical for automotive and industrial applications where fault conditions must be safely managed.
Can the LT3502AIMS#PBF regulate output voltages other than 3.3V?
Yes, the LT3502AIMS#PBF supports adjustable output voltages via the FB pin. With a resistor divider (R1/R2), VOUT = 0.8V × (1 + R1/R2). For example, using R2 = 10kΩ and R1 = 32.4kΩ yields 3.3V; R1 = 52.5kΩ yields 5.0V. The 0.8V reference is trimmed to ±1.6% over temperature, ensuring accuracy across operating conditions.
What is the purpose of the BOOST pin on the LT3502AIMS#PBF?
The BOOST pin on the LT3502AIMS#PBF provides gate drive voltage higher than VIN to fully saturate the internal bipolar NPN switch. It is charged via the internal Schottky diode and an external capacitor (typically 0.1µF) connected between BOOST and SW. Maintaining BOOST ≥2.2V above SW ensures low VCE(SAT) (~450mV) and high efficiency across the 3V–40V input range.
Is the LT3502AIMS#PBF pin-compatible with the LT3502IMS#PBF?
No, the LT3502AIMS#PBF and LT3502IMS#PBF are not pin-compatible. While both use the MSOP-10 package, the LT3502IMS#PBF is the base LT3502 variant (1.1MHz), whereas the LT3502AIMS#PBF is the LT3502A variant (2.2MHz) with updated internal timing and foldback thresholds. Their pin functions match, but electrical behavior-including frequency, current limit, and foldback trigger-differs per datasheet specifications.
LT3502AIMS#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 3V
- Voltage - Input (Max):
- 40V
- Voltage - Output (Min/Fixed):
- 0.8V
- Voltage - Output (Max):
- 32V
- Current - Output:
- 500mA
- Frequency - Switching:
- 2.25MHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-MSOP
LT3502AIMS#PBF FAQ
1.How can I place an order for LT3502AIMS#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3502AIMS#PBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LT3502AIMS#PBF reliable?
The price and inventory of LT3502AIMS#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT3502AIMS#PBF is usually 5 days.
3.What payment methods are accepted for LT3502AIMS#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3502AIMS#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3502AIMS#PBF?
LT3502AIMS#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3502AIMS#PBF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LT3502AIMS#PBF?
For technical support, including LT3502AIMS#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3502AIMS#PBF requirements.
6.How does Aetrix verify that LT3502AIMS#PBF is sourced from the original manufacturer or authorized distributors?
All LT3502AIMS#PBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LT3502AIMS#PBF meets industry standards.
7.What is the process for return or replacement of LT3502AIMS#PBF?
All LT3502AIMS#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3502AIMS#PBF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LT3502AIMS#PBF part is unused and in its original packaging.
Return procedure for LT3502AIMS#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3502AIMS#PBF Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
