My Inquiry
My Account
Analog Devices Inc. LTC3251EMSE-1.5#TRPBF
- Part No.:
- LTC3251EMSE-1.5#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width) Exposed Pad
- Datasheet:
-
LTC3251EMSE-1.5#TRPBF.pdf
- Description:
- IC REG CHARGE PUMP 1.5V 10MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,120
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3251EMSE-1.5#TRPBF from Analog Devices (formerly Linear Technology) is a 2-phase, spread spectrum charge pump DC/DC converter delivering a fixed 1.5V output at up to 500mA from a 2.7V–5.5V input. It eliminates inductors, achieves twice the efficiency of LDOs, and operates in Super Burst mode with only 10µA input current. It is used in space-constrained battery-powered systems such as cellular phones and portable DSP supplies.
For engineers reviewing the LTC3251EMSE-1.5#TRPBF datasheet, LTC3251EMSE-1.5#TRPBF pinout, LTC3251EMSE-1.5#TRPBF application, or LTC3251EMSE-1.5#TRPBF equivalent, key selection criteria include fixed 1.5V output regulation tolerance (±4%), 2-phase spread spectrum noise suppression, Super Burst mode current consumption (10µA), thermal shutdown protection (160°C), and MSOP-10 package compatibility with exposed GND pad soldering.
Technical Context
The LTC3251EMSE-1.5#TRPBF implements dual-phase switched-capacitor fractional conversion using two flying capacitors (C1, C2) driven by nonoverlapping clocks to deliver constant charge transfer and minimize input/output ripple. Its spread spectrum oscillator sweeps switching frequency between 0.7MHz and 2MHz to reduce EMI peaks.
Operating mode is selected via CMOS-compatible MD0/MD1 pins: Super Burst (MD0=VIN, MD1=VIN), Burst (MD0=VIN, MD1=0V), Continuous Spread Spectrum (MD0=0V, MD1=VIN), or Shutdown (both low). The MODE pin disables spread spectrum on LTC3251-1.5 variants, forcing fixed 1.6MHz operation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.5V ±4% over 3.5V–5.5V input and 0–500mA load; ensures stable core voltage for low-power processors. |
| Input Voltage Range | 2.7V to 5.5V; supports single-cell Li-ion (2.7–4.2V) and triple-cell NiMH (3.6–4.5V) battery inputs without external regulators. |
| Max Output Current | 500mA in continuous or Burst Mode; sufficient for powering DSPs, RF ICs, or memory subsystems in handheld devices. |
| Super Burst IIN | 10µA typical; enables multi-week standby in always-on sensor nodes or Bluetooth peripherals. |
| Spread Spectrum Freq | 0.7–2MHz randomization; reduces peak conducted EMI by >20dBm versus fixed-frequency converters, easing EMC compliance. |
| Thermal Protection | Auto-shutdown at ~160°C junction; re-enables at ~150°C; prevents permanent damage during sustained overload or poor PCB heatsinking. |
| Shutdown Current | 0.01µA typical; isolates VOUT from VIN and minimizes battery drain in off-state applications. |
Pinout & Package
The LTC3251EMSE-1.5#TRPBF is housed in a thermally enhanced 10-pin MSOP package with exposed GND pad (Pin 11) that must be soldered to the PCB for thermal and electrical performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (MD0) | Mode Control Input | CMOS logic input setting operating mode; threshold ~0.8V; must not float-drives Super Burst when high with MD1. |
| Pin 2 (VIN) | Main Power Input | 2.7–5.5V supply input; requires ≥1µF low-ESR ceramic bypass to GND near pin for stability. |
| Pin 3 (C1+) | Flying Capacitor 1 Anode | Connects to positive terminal of 1µF ceramic flying capacitor; handles high dv/dt transients-keep trace short and shielded. |
| Pin 4 (C1−) | Flying Capacitor 1 Cathode | Connects to negative terminal of same flying capacitor; forms charge transfer path with C1+ and internal switches. |
| Pin 5 & Pin 11 (GND) | Power Ground | Dual ground connections; Pin 11 is exposed thermal pad-must be soldered to solid GND plane for θJA = 40°C/W. |
| Pin 6 (C2−) | Flying Capacitor 2 Cathode | Completes second charge pump phase; paired with Pin 8 (C2+) to enable 2-phase interleaving and lower ripple. |
| Pin 7 (VOUT) | Regulated Output | Fixed 1.5V output; disconnects from VIN in shutdown; requires 10µF low-ESR (<0.08Ω) ceramic capacitor for stability. |
| Pin 8 (C2+) | Flying Capacitor 2 Anode | Second flying capacitor terminal; enables interleaved operation that halves effective ripple frequency and improves PSRR. |
| Pin 9 (MD1) | Mode Control Input | Second CMOS mode select; combined with MD0 to define all four operating modes including shutdown (both low). |
| Pin 10 (MODE) | Spread Spectrum Enable | On LTC3251-1.5 variants: low = spread spectrum enabled (0.7–2MHz); high = fixed 1.6MHz operation; threshold ≈ 0.5×VIN. |
Key Features
| Feature | Design Value |
|---|---|
| No-inductor architecture | Eliminates magnetic components and associated EMI, board area, and cost-ideal for ultra-thin mobile designs. |
| 2-phase spread spectrum | Reduces both input and output conducted noise peaks by >20dBm versus fixed-frequency converters, easing FCC/CE certification. |
| Super Burst mode | Draws only 10µA IIN while sustaining 40mA output-enables years of battery life in IoT endpoint sleep states. |
| Soft-start circuitry | Linearly ramps output current over ~500µs to limit inrush and prevent input rail collapse during power-up. |
| Short-circuit & thermal protection | Current-limits to ~800mA and cycles at 160°C/150°C thresholds-ensures robustness without external protection circuitry. |
Applications
| Cellular Phone Baseband | Portable Medical Sensor |
|---|---|
Use Scenario: Powers baseband processor core in GSM/UMTS smartphones operating from single Li-ion cell (3.0–4.2V). IC Role / Device Role / Timing Role: Fixed 1.5V step-down regulator replacing inefficient LDO; delivers 500mA peak current with minimal heat rise. Use Value: Doubles battery runtime versus LDO solution and eliminates inductor footprint-critical for <9mm Z-height designs. | Use Scenario: Supplies 1.5V to ultra-low-power ADC and BLE radio in wearable ECG patch with coin-cell battery. IC Role / Device Role / Timing Role: Primary power converter in always-on sensing mode; operates in Super Burst mode between measurement bursts. Use Value: 10µA quiescent current extends 3V CR2032 battery life to >2 years; spread spectrum avoids interference with sensitive analog front-end. |
| DSP Audio Processing Module | Industrial Handheld Scanner |
Use Scenario: Provides clean 1.5V rail to TI C55x DSP in portable audio recorder with flash storage and LCD backlight. IC Role / Device Role / Timing Role: High-efficiency, low-noise DC/DC converter supporting dynamic load steps up to 500mA during encode/decode bursts. Use Value: Dual-phase architecture limits output ripple to <15mV (10µF COUT), preventing audible noise in audio signal chain. | Use Scenario: Powers ARM Cortex-M4 MCU and laser driver in ruggedized barcode scanner powered by 3.6V NiMH pack. IC Role / Device Role / Timing Role: Main system regulator with shutdown control via host MCU GPIOs; withstands 85°C ambient and repeated thermal cycling. Use Value: Exposed-pad MSOP package and 125°C TJMAX ensure reliable operation in sealed enclosures without forced air cooling. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar charge pump DC/DC converter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS60403DBVR | Fixed 3.3V output; 60mA max; no spread spectrum; SOT-23-5 package. | Suitable only for low-current logic rails-not viable for 500mA 1.5V loads. | Select only if output voltage and current requirements align; not a functional substitute for LTC3251EMSE-1.5#TRPBF. |
| MAX8815AETE+T | Fixed 1.5V output; 400mA max; no Super Burst mode; 2.5µA shutdown current; 12-pin TQFN. | Lacks 2-phase noise reduction and 10µA Super Burst-higher light-load power consumption. | Consider for cost-sensitive designs where 100mA lower output current and higher quiescent current are acceptable. |
Compared with TPS60403DBVR and MAX8815AETE+T, the LTC3251EMSE-1.5#TRPBF uniquely combines 500mA capability, 10µA Super Burst operation, and 2-phase spread spectrum noise suppression in a thermally optimized MSOP package-making it the only option meeting full specification for high-efficiency, low-EMI 1.5V portable power.
Availability
LTC3251EMSE-1.5#TRPBF is available at Aetrix Electronics and suitable for cellular phone baseband, portable medical sensors, and industrial handheld scanners requiring stable component supply across long production lifecycles.
Supply support for LTC3251EMSE-1.5#TRPBF 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, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.
The LTC3251 family was designed by ADI's former Linear Technology division specifically for ultra-low-noise, inductorless power conversion in battery-powered portable electronics-emphasizing efficiency, EMI reduction, and minimal external component count.
FAQ
What is the output voltage accuracy of the LTC3251EMSE-1.5#TRPBF over temperature and load?
The LTC3251EMSE-1.5#TRPBF delivers 1.5V output with ±4% regulation tolerance across –40°C to 85°C ambient temperature and 0–500mA load current, as verified in the Electrical Characteristics table under "VOUT Regulation Voltage (LTC3251-1.5)" with conditions specified for each current range. This accuracy holds under Burst and Continuous modes but tightens to ±2.4% (1.44V–1.56V) in Super Burst mode at ≤40mA load.
Does the LTC3251EMSE-1.5#TRPBF require external compensation components?
No, the LTC3251EMSE-1.5#TRPBF is internally compensated and requires no external compensation network. Stability is ensured by proper selection of the 10µF low-ESR ceramic output capacitor and adherence to layout guidelines-including short traces to flying capacitors and grounding the exposed pad. The control loop uses the output capacitor itself as the dominant pole.
Can the LTC3251EMSE-1.5#TRPBF operate from a 2.7V input at full 500mA load?
Yes, the LTC3251EMSE-1.5#TRPBF supports 500mA output at 2.7V input-but only when operating in Continuous or Burst Mode and with VIN ≥ 3.5V per the minimum input requirement formula (VIN ≥ 2 × (VOUT + ROL × IOUT)). At 2.7V input, maximum sustainable load is reduced to ~100mA in Burst Mode and ~40mA in Super Burst Mode, as confirmed by the "1.5V Output Voltage vs Supply Voltage" curves.
How does spread spectrum operation affect EMI performance of the LTC3251EMSE-1.5#TRPBF?
Spread spectrum operation in the LTC3251EMSE-1.5#TRPBF reduces peak conducted EMI by >20dBm compared to fixed-frequency converters, as demonstrated in Figures 2b and 2c of the datasheet. By randomizing switching frequency between 0.7MHz and 2MHz, energy spreads across a broad band instead of concentrating at harmonics-enabling compliance with CISPR-22 Class B limits using only 1µF input and 10µF output capacitance.
Is the exposed pad (Pin 11) of the LTC3251EMSE-1.5#TRPBF electrically connected, and how must it be handled?
Yes, the exposed pad (Pin 11) of the LTC3251EMSE-1.5#TRPBF is electrically connected to GND and must be soldered to a solid PCB ground plane. Per the Package Information section, failure to solder this pad degrades thermal resistance (θJA rises from 40°C/W to >60°C/W) and compromises both electrical noise immunity and reliability under sustained 500mA load.
LTC3251EMSE-1.5#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width) Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Charge Pump
- Output Type:
- Fixed
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.7V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 1.5V
- Voltage - Output (Max):
- -
- Current - Output:
- 500mA
- Frequency - Switching:
- 1MHz ~ 1.6MHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-MSOP-EP
LTC3251EMSE-1.5#TRPBF FAQ
1.How can I place an order for LTC3251EMSE-1.5#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3251EMSE-1.5#TRPBF 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 LTC3251EMSE-1.5#TRPBF reliable?
The price and inventory of LTC3251EMSE-1.5#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3251EMSE-1.5#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC3251EMSE-1.5#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3251EMSE-1.5#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3251EMSE-1.5#TRPBF?
LTC3251EMSE-1.5#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3251EMSE-1.5#TRPBF 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 LTC3251EMSE-1.5#TRPBF?
For technical support, including LTC3251EMSE-1.5#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3251EMSE-1.5#TRPBF requirements.
6.How does Aetrix verify that LTC3251EMSE-1.5#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC3251EMSE-1.5#TRPBF 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 LTC3251EMSE-1.5#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC3251EMSE-1.5#TRPBF?
All LTC3251EMSE-1.5#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3251EMSE-1.5#TRPBF, 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 LTC3251EMSE-1.5#TRPBF part is unused and in its original packaging.
Return procedure for LTC3251EMSE-1.5#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3251EMSE-1.5#TRPBF 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…
