My Inquiry
My Account
Analog Devices Inc. LT1507IN8#PBF
- Part No.:
- LT1507IN8#PBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- 8-DIP (0.300", 7.62mm)
- Datasheet:
-
LT1507IN8#PBF.pdf
- Description:
- IC REG BUCK ADJ 1.5A 8PDIP
- Quantity:
- Payment:
- Shipping:
Inventory:2,647
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT1507IN8#PBF from Analog Devices (formerly Linear Technology) is a 500kHz monolithic buck mode switching regulator in 8-lead PDIP package, designed for 4V–15V input to fixed 3.3V output at up to 1.25A. It features current-mode control, 0.3Ω NPN switch on-resistance, 20µA shutdown current, and internal feedback divider for 3.3V regulation-used in portable computers and battery-powered systems.
For engineers reviewing the LT1507IN8#PBF datasheet, LT1507IN8#PBF pinout, LT1507IN8#PBF application, or LT1507IN8#PBF equivalent, key selection considerations include its fixed 3.3V output configuration, thermal shutdown and cycle-by-cycle current limiting, 500kHz constant-frequency operation, and compatibility with surface-mount inductors as small as 2µH.
Technical Context
The LT1507IN8#PBF implements a current-mode buck topology with an internal 500kHz oscillator, bipolar NPN power switch, and integrated error amplifier. Its BOOST pin enables saturation of the switch via external capacitor/diode, reducing conduction loss to ~0.3Ω and enabling >85% efficiency at 1.25A load with 5V→3.3V conversion.
It uses dual shutdown thresholds (2.38V for UVLO, 0.4V for deep shutdown), supports external synchronization from 580kHz to 1MHz, and includes frequency foldback and current limit foldback below 1V FB/SENSE voltage-critical for short-circuit protection without external circuitry.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | 500kHz ±40kHz (TYP); enables compact 2–5µH inductors and low-profile designs |
| Output Voltage | Fixed 3.3V ±1.5% (3.25–3.35V); internally trimmed, no external resistor divider required |
| Max Output Current | 1.25A continuous (at VIN=5V, TA=25°C); limited by thermal design and inductor rating |
| Input Voltage Range | 4V to 15V; minimum start-up voltage ~4.3V for 3.3V output |
| Shutdown Current | ≤50µA (TYP 20µA); reduces system standby power in battery applications |
| Switch RDS(on) | 0.3Ω (TYP); achieved via BOOST pin drive, enabling high efficiency vs. standard bipolar switches |
| Thermal Protection | Full thermal shutdown + cycle-by-cycle current limiting; prevents damage under overload or short-circuit |
Pinout & Package
LT1507IN8#PBF is housed in an 8-lead plastic DIP (PDIP) package (N8), rated for –40°C to +85°C operating ambient temperature. Pin spacing is 0.300", body width 0.355", and lead finish is matte tin.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - BOOST | Boost capacitor drive node | Provides elevated gate drive to saturate internal NPN switch; requires external 3.3nF capacitor to VIN |
| 2 - VIN | Main power input | Accepts 4V–15V; supplies bias and switch current; must be bypassed with ≥10µF ceramic/tantalum |
| 3 - VSW | Switch collector node | Drives external catch diode (e.g., 1N5818); swings from VIN to ~–0.7V during off-time |
| 4 - SHDN | Shutdown control input | Logic-compatible; 0V = full shutdown (20µA IQ), 2.38V = UVLO disable, >2.38V = normal operation |
| 5 - SYNC | External clock synchronization | Accepts 580kHz–1MHz logic-level signal; overrides internal oscillator for EMI reduction or multi-rail sync |
| 6 - GND | Power and signal reference | Common return for VIN, BOOST, VSW, and internal circuits; requires low-impedance PCB plane |
| 7 - FB/SENSE | Output voltage sense input | Internally connected to 3.3V output; used for regulation and foldback protection (current/frequency reduction below 1.5V) |
| 8 - VC | Error amplifier output | Controls peak switch current; used for compensation (capacitor from VC to GND), or override/clamp |
Key Features
| Feature | Design Value |
|---|---|
| Constant 500kHz switching | Enables predictable EMI filtering and consistent inductor sizing across designs |
| Saturated NPN switch (0.3Ω) | Reduces conduction loss vs. conventional bipolar regulators, improving efficiency at high load |
| Integrated 3.3V feedback divider | Eliminates external resistors; ensures accurate, stable output without trimming or layout sensitivity |
| Foldback current & frequency limiting | Automatically reduces switch current and frequency during short-circuit, limiting IC and diode power dissipation |
| External synchronization support | Allows noise-sensitive systems to align switching edges with other clocks or avoid critical frequency bands |
Applications
| Portable Computing Power | Battery-Powered Instrumentation |
|---|---|
Use Scenario: Step-down supply for 3.3V logic rails in handheld test equipment powered by Li-ion batteries (3.6V–4.2V nominal). IC Role / Device Role / Timing Role: Primary DC/DC converter delivering regulated 3.3V to microcontroller, ADC, and interface ICs. Use Value: High light-load efficiency (4mA quiescent current) extends battery life; 20µA shutdown preserves charge during sleep modes. | Use Scenario: Compact 5V-to-3.3V conversion in field-deployable sensor nodes where board space and thermal management are constrained. IC Role / Device Role / Timing Role: Fixed-output buck regulator powering low-power wireless transceivers and analog front-ends. Use Value: 8-lead PDIP package allows through-hole prototyping and rework; thermal shutdown prevents failure in sealed enclosures. |
| Battery Charger Auxiliary Rail | Distributed Low-Voltage Power |
Use Scenario: Generating isolated 3.3V bias for charger controller ICs and status LEDs in multi-cell Li-ion charging systems (input 9–15V). IC Role / Device Role / Timing Role: Secondary regulator fed from main charger output, providing clean 3.3V independent of charging state. Use Value: Input range down to 4V supports operation during low-battery pre-charge phase; cycle-by-cycle current limiting protects against transient overloads. | Use Scenario: Local point-of-load regulation for 3.3V FPGA I/O banks in industrial backplanes with distributed 5V or 12V intermediate bus. IC Role / Device Role / Timing Role: Standalone buck converter mounted near load to minimize IR drop and noise coupling. Use Value: 500kHz operation allows use of small, low-profile 5µH inductors; SYNC pin enables synchronization with system clock to reduce beat frequencies. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3605EDE#PBF | 4MHz synchronous buck, 3.3V fixed, 1.2A, 20V max input, integrated MOSFETs | Higher frequency enables smaller LC components; no external catch diode needed | Preferred for space-constrained designs requiring higher efficiency and lower EMI; not pin-compatible |
| LM2678-3.3 | 63kHz buck, 3.3V fixed, 5A, 40V max input, external diode, larger inductor required | Lower switching frequency increases inductor size but improves light-load efficiency | Used where cost and ruggedness outweigh size constraints; requires different compensation and layout |
Compared with LTC3605EDE#PBF, LT1507IN8#PBF offers lower BOM count with external diode flexibility and proven thermal robustness in legacy designs; compared with LM2678-3.3, it delivers superior power density and transient response due to 500kHz current-mode architecture-but requires tighter layout attention for EMI control.
Availability
LT1507IN8#PBF is available at Aetrix Electronics and suitable for portable computing, battery-powered instrumentation, and distributed low-voltage power applications requiring stable component supply, long-term lifecycle support, and industrial-grade temperature performance.
Supply support for LT1507IN8#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 and maintains full support for legacy Linear power products. The company specializes in high-performance analog, mixed-signal, and power management ICs.
The LT1507IN8#PBF belongs to Linear's monolithic buck regulator product line, engineered for high-efficiency, low-noise DC/DC conversion in space- and thermal-constrained portable and industrial systems.
FAQ
What is the maximum output current capability of the LT1507IN8#PBF?
The LT1507IN8#PBF delivers up to 1.25A continuous output current under typical conditions (VIN = 5V, TA = 25°C, proper thermal layout). This is limited by internal switch current limit (1.5A typ), inductor saturation, and PCB thermal resistance. At higher ambient temperatures or with poor heatsinking, derating is required-e.g., ~0.9A at 85°C ambient per thermal data.
Does the LT1507IN8#PBF require an external feedback resistor network?
No. The LT1507IN8#PBF is the fixed 3.3V output variant and includes internal feedback resistors. Pin 7 (FB/SENSE) connects directly to the internal 3.3V output node and serves only as a sense and protection pin-not as a programmable feedback input. External resistors are unnecessary and would disrupt regulation.
Can the LT1507IN8#PBF be synchronized to an external clock?
Yes. The LT1507IN8#PBF supports external synchronization via Pin 5 (SYNC), accepting logic-level signals from 580kHz to 1MHz. The input is TTL/CMOS compatible (1.5–2.2V threshold), and duty cycle between 10% and 90% is acceptable. Synchronization eliminates beat frequencies and aids EMI compliance in multi-rail systems.
What is the purpose of the BOOST pin on the LT1507IN8#PBF?
The BOOST pin (Pin 1) provides elevated drive voltage to the base of the internal NPN power switch, enabling saturation and minimizing VCE(sat). It requires an external 3.3nF capacitor connected between BOOST and VIN. Without this, switch losses increase significantly-efficiency drops from >85% to ~70%, and thermal stress rises.
How does the LT1507IN8#PBF handle short-circuit conditions?
The LT1507IN8#PBF employs dual protection: cycle-by-cycle current limiting (1.5A typ) and automatic foldback. When FB/SENSE voltage falls below 1.5V, peak switch current reduces; below 1V, switching frequency drops ~5:1. This limits power dissipation in the IC, catch diode, and inductor during sustained shorts-preventing thermal runaway without external circuitry.
LT1507IN8#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 8-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 4V
- Voltage - Input (Max):
- 16V
- Voltage - Output (Min/Fixed):
- 2.42V
- Voltage - Output (Max):
- 14.88V
- Current - Output:
- 1.5A
- Frequency - Switching:
- 500kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 8-PDIP
LT1507IN8#PBF FAQ
1.How can I place an order for LT1507IN8#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT1507IN8#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 LT1507IN8#PBF reliable?
The price and inventory of LT1507IN8#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT1507IN8#PBF is usually 5 days.
3.What payment methods are accepted for LT1507IN8#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT1507IN8#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT1507IN8#PBF?
LT1507IN8#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT1507IN8#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 LT1507IN8#PBF?
For technical support, including LT1507IN8#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT1507IN8#PBF requirements.
6.How does Aetrix verify that LT1507IN8#PBF is sourced from the original manufacturer or authorized distributors?
All LT1507IN8#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 LT1507IN8#PBF meets industry standards.
7.What is the process for return or replacement of LT1507IN8#PBF?
All LT1507IN8#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LT1507IN8#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 LT1507IN8#PBF part is unused and in its original packaging.
Return procedure for LT1507IN8#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT1507IN8#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…
