My Inquiry
My Account
Analog Devices Inc. LTC3256MPMSE#PBF
- Part No.:
- LTC3256MPMSE#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Voltage Regulators - Linear + Switching
- Package:
- 16-TFSOP (0.118", 3.00mm Width) Exposed Pad
- Datasheet:
-
LTC3256MPMSE#PBF.pdf
- Description:
- IC REG DL BUCK/LINEAR 16MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,296
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3256MPMSE#PBF from Analog Devices (formerly Linear Technology) is a wide-input-range switched-capacitor dual-output DC/DC converter with integrated watchdog timer and power-good monitoring. It delivers regulated 5V (100mA max) and 3.3V (250mA max) outputs from 5.5V–38V input, uses automatic 2:1/1:1 charge pump mode switching for efficiency optimization, and operates across –55°C to 150°C junction temperature. It serves as a high-efficiency housekeeping supply in automotive ECUs and industrial control systems.
For engineers reviewing the LTC3256MPMSE#PBF datasheet, LTC3256MPMSE#PBF pinout, LTC3256MPMSE#PBF application, or LTC3256MPMSE#PBF equivalent, key selection considerations include its dual fixed-output architecture, 16-lead MSOP thermal package with exposed pad, integrated 1.1V diagnostic reference, independent enable control per output, and ISO 26262 diagnostic coverage support for functional safety designs.
Technical Context
The LTC3256MPMSE#PBF implements a multimode step-down charge pump pre-regulator feeding both outputs: OUTCP (5.05V nominal) powers the 3.3V LDO, while OUT5 is supplied either from OUTCP via a fault-protected PMOS switch (2:1 mode, VIN > ~10.1V) or directly from VIN via a gated 1:1 regulator (VIN < ~10.1V). Mode switching is fully automatic and transparent to system control logic.
It integrates independent power-good comparators (PG3/PG5), a reset controller with adjustable timeout (RT pin), a watchdog timer with configurable upper/lower boundaries (WT/WDI pins), overcurrent protection per output, overtemperature shutdown at 150°C, and a buffered 1.1V reference (REFOUT) with 2kΩ output impedance for system self-test.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 5.5V to 38V - supports 12V/24V automotive and industrial rails with tolerance for load-dump transients up to 38V. |
| 5V Output Capability | Fixed 5V ±2%, 100mA max - delivered via internal PMOS switch from OUTCP or VIN-powered 1:1 regulator depending on input voltage. |
| 3.3V Output Capability | Fixed 3.3V ±3.5%, 250mA max - low-dropout linear regulator powered exclusively by OUTCP charge pump output. |
| Quiescent Current | 20µA (both outputs regulating, no load) - enables ultra-low-power standby operation in always-on systems. |
| Operating Junction Temp | –55°C to 150°C - qualified for extended-temperature automotive and harsh-environment industrial applications. |
| Charge Pump Modes | Automatic 2:1 (VIN/2) and 1:1 - maximizes efficiency across input range; reduces power dissipation by >2W vs dual-LDO at 12V/350mA. |
| Diagnostic Features | 1.1V buffered reference (±3%), independent PG outputs, RSTI comparator, RT/WT timing pins - supports ASIL-B diagnostic coverage per ISO 26262. |
Pinout & Package
Package: 16-lead plastic MSOP with thermally enhanced exposed pad (Pin 17 = GND), θJA = 40°C/W, θJC = 10°C/W. Exposed pad must be soldered to PCB ground plane for thermal and electrical performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| C– (1) | Flying capacitor negative terminal | Connects to negative side of external ceramic flying capacitor (≥0.4µF, ≥6V rating); critical for charge pump energy transfer. |
| C+ (2) | Flying capacitor positive terminal | Connects to positive side of flying capacitor; forms charge-transfer path with C– during 2:1/1:1 switching cycles. |
| OUTCP (3) | Charge pump output | Regulated ~5.05V output; powers OUT3 LDO and feeds OUT5 switch; requires ≥10µF X7R ceramic bypass. |
| OUT5 (4) | 5V regulated output | Fixed 5V output enabled by EN5; sourced from OUTCP (2:1 mode) or VIN (1:1 mode); max 100mA. |
| REFOUT (5) | Buffered 1.1V reference | Stable diagnostic reference for system self-test; 2kΩ output impedance; bypass with 0.1µF ceramic. |
| OUT3 (6) | 3.3V LDO output | Fixed 3.3V output enabled by EN3; powered only by OUTCP; max 250mA; low-noise linear regulation. |
| PG3 (7) | 3.3V power-good indicator | Open-drain output pulled high externally; goes Hi-Z when OUT3 reaches 97.5% of regulation. |
| PG5 (8) | 5V power-good indicator | Open-drain output pulled high externally; goes Hi-Z when OUT5 reaches 97.5% of regulation. |
| RST (9) | Reset logic output | Open-drain reset signal asserted low during reset timeout; pulled high externally to OUT3/OUT5/OUTCP. |
| WT (10) | Watchdog timer control | Connect external capacitor to GND to set watchdog upper boundary; tie to OUTCP for ~1.6s default. |
| RT (11) | Reset timeout control | Connect external capacitor to GND to set reset duration; tie to OUTCP for ~200ms default; open for minimum timeout. |
| RSTI (12) | Reset input comparator | Logic input compared to 1.2V threshold; falling edge below threshold initiates reset sequence. |
| WDI (13) | Watchdog input | Must be toggled within watchdog window (tWDL < t < tWDU); tie to GND with WT to disable. |
| VIN (14) | Main power input | 5.5V–38V supply for charge pump and internal circuitry; requires ≥10µF low-ESR ceramic bypass. |
| EN3 (15) | 3.3V output enable | Active-high logic input; enables OUT3 and triggers charge pump startup; tolerates 38V; 1µA pull-down. |
| EN5 (16) | 5V output enable | Active-high logic input; enables OUT5 and triggers charge pump startup; tolerates 38V; 1µA pull-down. |
| GND (17) | Ground / Exposed Pad | System ground connection; exposed thermal pad must be soldered to PCB ground plane for thermal integrity. |
Key Features
| Feature | Design Value |
|---|---|
| Inductorless architecture | Eliminates magnetic components and EMI from inductors-ideal for space-constrained and noise-sensitive automotive modules. |
| Automatic mode switching | Seamlessly transitions between 2:1 and 1:1 charge pump modes without external control or firmware intervention. |
| Dual independent enable inputs | EN3 and EN5 allow flexible power sequencing and dynamic output control-enables partial system wake-up and power gating. |
| Integrated diagnostic resources | 1.1V REFOUT, RSTI comparator, RT/WT timing pins, and PG outputs provide hardware-level fault detection and system-level safety monitoring. |
| Extended temperature qualification | MP-grade (–55°C to 150°C) operation verified and tested-meets requirements for under-hood automotive and industrial edge computing. |
Applications
| Automotive ECU Housekeeping Supply | Industrial PLC I/O Module Power |
|---|---|
Use Scenario: Powers microcontroller, CAN transceiver, and sensor interface circuitry in engine control units operating across cold-crank (5.5V) to load-dump (38V) conditions. IC Role / Device Role / Timing Role: Dual-output DC/DC converter providing isolated 5V (CAN PHY) and 3.3V (MCU core) rails with independent enable and power-good signaling. Use Value: Reduces thermal load by >2W vs dual-LDO at full load; eliminates inductor size/EMI concerns; supports ISO 26262 ASIL-B diagnostics via REFOUT and RSTI. | Use Scenario: Supplies field-side 3.3V logic and 5V analog front-end in programmable logic controller I/O modules deployed in factory automation environments. IC Role / Device Role / Timing Role: High-reliability housekeeping supply delivering stable outputs across wide input range and extended temperature extremes (–40°C to +85°C ambient). Use Value: Enables single-rail 24V input design with no external inductors; 150°C junction rating ensures long-term reliability in sealed enclosures; PG3/PG5 simplify power sequencing verification. |
| Telecom Remote Radio Unit (RRU) Bias Supply | Low-Power 12V-to-Dual-Rail Conversion |
Use Scenario: Generates bias voltages for RF amplifiers and ADC/DAC interfaces in outdoor telecom base station remote radio units exposed to wide ambient temperature swings. IC Role / Device Role / Timing Role: Efficient dual-output converter with watchdog timer and reset supervision-ensures reliable restart after brownout or software hang. Use Value: Integrated WDI/WT/RSTI functions replace discrete supervisor ICs; 1.1V REFOUT enables periodic calibration checks; MP-grade operation supports –40°C to +85°C ambient with margin. | Use Scenario: Replaces inefficient dual-LDO solutions in battery-backed instrumentation where 12V input must generate clean 5V and 3.3V for MCU and peripherals. IC Role / Device Role / Timing Role: Step-down charge pump regulator with soft-start, independent enable, and low-quiescent-current shutdown (0.5µA). Use Value: Extends battery life via 20µA no-load IQ and 0.5µA shutdown; eliminates inductor losses; compact MSOP package saves board area versus discrete buck + LDO solution. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-output DC/DC converter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3265EMSE#PBF | Single 3.3V output (250mA), no 5V rail; includes inverting charge pump for negative bias; lower IQ (12µA); same MSOP package. | Not suitable for 5V-dependent peripherals (e.g., CAN transceivers); better for systems needing ±3.3V or low-noise analog bias. | Select LTC3265EMSE#PBF only if dual-rail requirement is replaced by need for negative voltage generation or lower quiescent current. |
| TPS65270QPWPRQ1 | Two synchronous buck regulators (3A/2A); requires external inductors; higher output current; no integrated watchdog or REFOUT; AEC-Q100 qualified. | Supports high-current loads but adds inductor cost/size/EMI; lacks built-in diagnostics for functional safety; wider VIN (4.5V–28V). | Select TPS65270QPWPRQ1 when >250mA 3.3V or >100mA 5V output current is required and inductor-based design is acceptable. |
Compared with LTC3256MPMSE#PBF, LTC3265EMSE#PBF omits the 5V output and diagnostic features but offers lower IQ and negative rail capability, while TPS65270QPWPRQ1 provides higher current and AEC-Q100 qualification but requires inductors and lacks integrated safety monitors-making LTC3256MPMSE#PBF optimal for compact, diagnostic-rich, inductorless dual-rail applications.
Availability
LTC3256MPMSE#PBF is available at Aetrix Electronics and suitable for automotive ECU power supplies, industrial PLC housekeeping circuits, and telecom remote radio unit biasing requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LTC3256MPMSE#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 its precision analog and power management portfolio with rigorous automotive and industrial qualification standards.
The LTC3256 belongs to Linear's high-reliability switched-capacitor power converter family, designed specifically for inductorless, wide-VIN, dual-output housekeeping supplies in safety-critical automotive and industrial systems.
FAQ
What is the maximum junction temperature specification for the LTC3256MPMSE#PBF?
The LTC3256MPMSE#PBF is fully tested and guaranteed over a junction temperature range of –55°C to 150°C. This extended rating exceeds standard automotive Grade 1 (–40°C to 125°C) and supports under-hood deployment and industrial edge applications where ambient temperatures exceed 105°C. Thermal derating above 125°C is documented in the datasheet's thermal management section.
How does the LTC3256MPMSE#PBF handle input voltage transitions between 2:1 and 1:1 charge pump modes?
Mode switching in the LTC3256MPMSE#PBF is fully autonomous and seamless: it operates in 2:1 mode (VOUTCP ≈ VIN/2) down to ~7.2V input, then transitions to 1:1 mode as needed to maintain 3.3V LDO regulation. The 5V output automatically switches from OUTCP to VIN-powered regulation when VOUTCP drops below 5V (~VIN < 10.1V). No external control or configuration is required.
Can the LTC3256MPMSE#PBF be used without external timing capacitors on RT and WT pins?
Yes-the LTC3256MPMSE#PBF operates with RT and WT pins left unconnected (open) for minimum reset timeout (~150ms internal) and disabled watchdog functionality. Alternatively, tying RT or WT to OUTCP configures fixed timeouts (~200ms reset, ~1.6s watchdog). External capacitors are optional for precise timing adjustment and are not required for basic operation.
What is the purpose of the REFOUT pin on the LTC3256MPMSE#PBF, and how is it used in system design?
The REFOUT pin on the LTC3256MPMSE#PBF delivers a buffered 1.1V ±3% reference with 2kΩ output impedance, intended for system-level self-test and diagnostic functions in safety-critical applications. It is commonly used to calibrate ADC references, verify voltage monitor thresholds, or validate analog sensor signal chains-enabling ISO 26262 ASIL-B diagnostic coverage without external precision references.
Does the LTC3256MPMSE#PBF support independent power sequencing of its 5V and 3.3V outputs?
Yes-the LTC3256MPMSE#PBF supports full independent sequencing via dedicated EN3 and EN5 logic inputs. Asserting EN3 first enables the charge pump and brings up OUT3 with controlled soft-start; EN5 can be asserted later to enable OUT5. Power-good signals PG3 and PG5 provide status feedback, enabling FPGA or MCU-controlled sequencing without additional supervisors.
LTC3256MPMSE#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 16-TFSOP (0.118", 3.00mm Width) Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Topology:
- Step-Down (Buck) (1), Linear (LDO) (1)
- Number of Outputs:
- 2
- Frequency - Switching:
- -
- Voltage/Current - Output 1:
- 5V, 100mA
- Voltage/Current - Output 2:
- 3.3V, 250mA
- Voltage/Current - Output 3:
- -
- w/LED Driver:
- No
- w/Supervisor:
- No
- w/Sequencer:
- Yes
- Voltage - Supply:
- 5.5V ~ 38V
- Operating Temperature:
- -55°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-MSOP-EP
LTC3256MPMSE#PBF FAQ
1.How can I place an order for LTC3256MPMSE#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3256MPMSE#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 LTC3256MPMSE#PBF reliable?
The price and inventory of LTC3256MPMSE#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3256MPMSE#PBF is usually 5 days.
3.What payment methods are accepted for LTC3256MPMSE#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3256MPMSE#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3256MPMSE#PBF?
LTC3256MPMSE#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3256MPMSE#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 LTC3256MPMSE#PBF?
For technical support, including LTC3256MPMSE#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3256MPMSE#PBF requirements.
6.How does Aetrix verify that LTC3256MPMSE#PBF is sourced from the original manufacturer or authorized distributors?
All LTC3256MPMSE#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 LTC3256MPMSE#PBF meets industry standards.
7.What is the process for return or replacement of LTC3256MPMSE#PBF?
All LTC3256MPMSE#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3256MPMSE#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 LTC3256MPMSE#PBF part is unused and in its original packaging.
Return procedure for LTC3256MPMSE#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3256MPMSE#PBF Tags
-
TPS6521905RHBR
Texas Instruments
-
MIC3385YHL-TR
Microchip Technology
-
A4402ELPTR-T
Allegro MicroSystems
-
LM26480SQ-AA/NOPB
Texas Instruments
-
A4402KLPTR-T
Allegro MicroSystems
-
BD71847AMWV-E2
ROHM Semiconductor
-
ADP5040ACPZ-1-R7
Analog Devices Inc.
-
LT3048IDC#TRPBF
Analog Devices Inc.
-
ADP5037ACPZ-R7
Analog Devices Inc.
-
XRP7714ILB-F
MaxLinear, Inc.
-
LTC3260EDE#TRPBF
Analog Devices Inc.
-
LTC3260EMSE#PBF
Analog Devices Inc.
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…
