My Inquiry
My Account
Analog Devices Inc. LTC1877EMS8#PBF
- Part No.:
- LTC1877EMS8#PBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
LTC1877EMS8#PBF.pdf
- Description:
- IC REG BUCK ADJ 600MA 8MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,389
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC1877EMS8#PBF from Analog Devices (formerly Linear Technology) is a monolithic synchronous step-down DC/DC regulator with constant-frequency current-mode control, 550kHz switching, 0.8V reference, and 600mA output capability at 5V input. It delivers up to 95% efficiency, supports 2.65V–10V input, and enables low-dropout operation via 100% duty cycle-ideal for single/dual Li-Ion portable systems including cellular telephones and wireless modems.
For engineers reviewing the LTC1877EMS8#PBF datasheet, LTC1877EMS8#PBF pinout, LTC1877EMS8#PBF application, or LTC1877EMS8#PBF equivalent, key selection considerations include its 10μA operating quiescent current, ±2% output voltage accuracy, Burst Mode® vs pulse-skipping mode selection via SYNC/MODE pin, internal P/N-channel MOSFET RDS(ON) values (0.65Ω/0.75Ω), and MSOP-8 thermal performance (θJA = 150°C/W).
Technical Context
The LTC1877EMS8#PBF implements a fixed-frequency current-mode buck architecture with integrated 600mA P-channel high-side and N-channel synchronous rectifier switches. Its error amplifier drives the ITH pin to regulate peak inductor current, while the 0.8V feedback reference enables precise output programming down to sub-1V levels.
Frequency synchronization is achieved via a digital phase/frequency detector and voltage-controlled oscillator (400–700kHz range), with PLL LPF pin controlling VCO frequency through external RC filtering. Burst Mode® operation is disabled during sync, enforcing pulse-skipping PWM with reduced audio noise-critical for battery-powered audio-sensitive applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.65V to 10V - supports single (3.0–4.2V) and dual (6.0–8.4V) Li-Ion battery stacks without external LDO pre-regulation. |
| Output Current | 600mA at VIN = 5V - sufficient for baseband processors, RF transceivers, and sensor subsystems in portable instrumentation. |
| Switching Frequency | 550kHz (internal) or 400–700kHz (externally synchronized) - enables use of compact 10μH inductors and ceramic output capacitors. |
| Quiescent Current | 10μA in operation, <1μA in shutdown - extends runtime in always-on monitoring and low-power sleep states. |
| Feedback Reference | 0.8V ±2% - allows accurate low-VOUT regulation (e.g., 1.2V, 1.5V, 1.8V) using standard resistor ratios with minimal divider current error. |
| RDS(ON) (P-MOSFET) | 0.65Ω (typ) at ISW = 100mA - limits conduction loss in high-duty-cycle dropout conditions (e.g., VIN = 3.3V → VOUT = 3.0V). |
| RDS(ON) (N-MOSFET) | 0.75Ω (typ) at ISW = −100mA - eliminates need for external Schottky diode and improves light-load efficiency over asynchronous designs. |
| Protection Features | Overcurrent, overtemperature, and output overvoltage lockout (ΔVOVL = 20–110mV above VFB) - ensures robust operation under fault and transient conditions. |
Pinout & Package
Package: 8-lead MSOP (MS8), 3mm × 3mm × 0.85mm body, exposed pad not electrically connected, θJA = 150°C/W.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| RUN (Pin 1) | Enable/disable control input | Pull below 0.4V to enter <1μA shutdown; pull above 1.2V to enable - prevents floating-induced erratic startup. |
| ITH (Pin 2) | Error amplifier compensation node | Voltage sets peak inductor current threshold (0.5V–1.9V range); used for loop stability tuning and current limit adjustment. |
| VFB (Pin 3) | Feedback input | Compares resistive divider output against 0.8V reference to regulate VOUT; high-impedance (≤30nA bias) minimizes divider error. |
| GND (Pin 4) | Analog and power ground | Common return for feedback, error amp, and internal circuitry - must be low-inductance connection to minimize noise coupling. |
| SW (Pin 5) | Switch node | Connects to inductor; carries high di/dt square-wave current - requires tight layout and Kelvin routing to reduce EMI and voltage spikes. |
| VIN (Pin 6) | Main power input | Supplies internal circuitry and high-side switch; requires local 10μF ceramic decoupling directly to GND (Pin 4). |
| SYNC/MODE (Pin 7) | Sync clock input / mode select | Tie to VIN for Burst Mode®; ground for pulse-skipping; apply 400–700kHz clock for synchronization - disables Burst Mode when active. |
| PLL LPF (Pin 8) | Phase detector output / VCO control | Drives external RC filter to set VCO frequency during sync; open when unused - voltage range 0–2.4V maps to 400–700kHz. |
Key Features
| Feature | Design Value |
|---|---|
| Synchronous rectification | Integrated N-channel MOSFET replaces Schottky diode - eliminates forward drop loss and improves efficiency by 3–8% at medium loads. |
| 100% duty cycle operation | Enables dropout regulation down to VIN − VDS(ON) - extends usable battery voltage range and delays system brownout in Li-Ion discharge profiles. |
| Selectable light-load modes | Burst Mode® (high efficiency, audible ripple) or pulse-skipping (low ripple, lower efficiency <50mA) - configurable per application noise sensitivity. |
| Internal current-mode control | Provides inherent cycle-by-cycle current limiting and excellent line/load transient response without external compensation components. |
| Robust protection suite | Thermal shutdown, overcurrent foldback (to ~80kHz during short-circuit), and output overvoltage lockout - prevents damage during abnormal operating conditions. |
| Low-noise synchronization interface | Digital PLL with zero-degree phase shift locks SW edge to external clock rising edge - avoids beat frequencies in multi-rail synchronized systems. |
Applications
| Cellular Telephones | Wireless Modems |
|---|---|
Use Scenario: Powering baseband processor core and I/O rails from single Li-Ion cell (3.0–4.2V). IC Role / Device Role / Timing Role: Primary buck regulator delivering 1.2V/600mA and 3.3V/300mA with dynamic voltage scaling support. Use Value: 10μA quiescent current preserves standby time; 100% duty cycle maintains regulation until battery reaches 3.0V. | Use Scenario: Supplying RF transceiver, PA bias, and USB PHY in LTE/5G edge modems. IC Role / Device Role / Timing Role: High-efficiency point-of-load converter with low EMI profile for noise-sensitive RF sections. Use Value: Synchronization to system clock eliminates switching noise heterodyning; Burst Mode® enables >85% efficiency at 1mA sleep current. |
| Portable Instruments | Battery-Powered Equipment |
Use Scenario: Regulating ADC reference, microcontroller core, and sensor interface in handheld DMMs or gas analyzers. IC Role / Device Role / Timing Role: Precision low-noise supply with ±2% output accuracy and <100mVpp ripple in pulse-skipping mode. Use Value: 0.8V reference enables stable 2.5V rail generation via 2.125kΩ/1kΩ divider; low RDS(ON) minimizes load regulation error. | Use Scenario: Power management in ruggedized barcode scanners, portable medical monitors, and handheld POS terminals. IC Role / Device Role / Timing Role: Main system regulator supporting wide input (2.65–10V) to accommodate varying battery chemistries and adapter inputs. Use Value: Overtemperature and overcurrent protection ensure reliability in unventilated enclosures; MSOP-8 footprint simplifies thermal design. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS62231DRYR | 3MHz fixed-frequency, 600mA, 2.05–6.5V input, 0.6V reference, no sync input, smaller 6-pin WSON package | Higher switching frequency enables smaller passives but increases gate charge loss; lacks frequency synchronization and Burst Mode® | Preferred for space-constrained designs where ultra-small inductors are prioritized over audio noise performance. |
| MAX17503GCU+T | 2.5–60V input, 600mA, 1.2MHz, adjustable soft-start, integrated MOSFETs, no 0.8V reference (adjustable via resistor) | Wider VIN range suits industrial battery packs; higher frequency and different reference require redesign of feedback network and compensation. | Selected when input exceeds 10V or when extended temperature range (−40°C to +125°C) is required beyond LTC1877EMS8#PBF's −40°C to +85°C rating. |
Compared with TPS62231DRYR and MAX17503GCU+T, the LTC1877EMS8#PBF uniquely balances ultra-low quiescent current (10μA), factory-trimmed 0.8V reference, and flexible mode selection (Burst/PWM/sync) - making it optimal for Li-Ion portable devices demanding long battery life and audio-grade low-noise operation.
Availability
LTC1877EMS8#PBF is available at Aetrix Electronics and suitable for cellular telephones, wireless modems, portable instruments, and battery-powered equipment requiring stable component supply across production lifecycles.
Supply support for LTC1877EMS8#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, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving precision instrumentation, communications, and industrial markets.
The LTC1877EMS8#PBF belongs to Linear Technology's legacy µPower synchronous buck regulator product line, designed specifically for high-efficiency, low-quiescent-current power conversion in portable Li-Ion applications.
FAQ
What is the maximum continuous output current of the LTC1877EMS8#PBF?
The LTC1877EMS8#PBF delivers up to 600mA continuous output current when VIN = 5V, as specified in the Electrical Characteristics table. At lower input voltages (e.g., 2.65V), maximum output current decreases due to increased conduction losses and thermal constraints - Figure 1 in the datasheet shows derating curves for various VOUT settings. Thermal performance in the MSOP-8 package (θJA = 150°C/W) must be considered for sustained full-load operation.
How does the SYNC/MODE pin configure operating mode on the LTC1877EMS8#PBF?
The SYNC/MODE pin on the LTC1877EMS8#PBF serves dual functions: tying it to VIN enables Burst Mode® operation for highest light-load efficiency, grounding it selects pulse-skipping PWM mode for lower output ripple, and applying a 400–700kHz external clock synchronizes switching while disabling Burst Mode®. The pin has a defined threshold (0.3V–1.5V) and leakage current (±1μA), and must never be left floating to prevent undefined behavior.
Can the LTC1877EMS8#PBF operate with input voltage below 2.65V?
No, the LTC1877EMS8#PBF has a minimum specified input voltage of 2.65V per Absolute Maximum Ratings and Electrical Characteristics. Operation below this level is not guaranteed and may result in improper regulation, failure to start, or undefined behavior of internal circuits such as the bandgap reference and oscillator. For sub-2.65V applications, consider the LTC1878 or other dedicated low-VIN regulators.
What is the purpose of the PLL LPF pin on the LTC1877EMS8#PBF?
The PLL LPF pin on the LTC1877EMS8#PBF is the output of the phase detector and control input to the voltage-controlled oscillator (VCO) within the synchronization PLL. When externally synchronized, an external RC filter (e.g., 10kΩ + 2200pF) is connected from this pin to GND to smooth phase error current and set VCO frequency. Its voltage (0–2.4V) linearly corresponds to 400–700kHz; when unused, it may be left open.
Does the LTC1877EMS8#PBF require an external Schottky diode?
No, the LTC1877EMS8#PBF does not require an external Schottky diode because it integrates both a P-channel high-side switch and an N-channel synchronous rectifier. This synchronous topology eliminates the forward voltage drop and associated power loss of a discrete diode, improving efficiency-especially at medium to high loads-and reducing thermal stress and board area.
LTC1877EMS8#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-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):
- 2.65V
- Voltage - Input (Max):
- 10V
- Voltage - Output (Min/Fixed):
- 0.8V
- Voltage - Output (Max):
- 10V
- Current - Output:
- 600mA
- Frequency - Switching:
- 550kHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-MSOP
LTC1877EMS8#PBF FAQ
1.How can I place an order for LTC1877EMS8#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC1877EMS8#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 LTC1877EMS8#PBF reliable?
The price and inventory of LTC1877EMS8#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC1877EMS8#PBF is usually 5 days.
3.What payment methods are accepted for LTC1877EMS8#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC1877EMS8#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC1877EMS8#PBF?
LTC1877EMS8#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC1877EMS8#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 LTC1877EMS8#PBF?
For technical support, including LTC1877EMS8#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC1877EMS8#PBF requirements.
6.How does Aetrix verify that LTC1877EMS8#PBF is sourced from the original manufacturer or authorized distributors?
All LTC1877EMS8#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 LTC1877EMS8#PBF meets industry standards.
7.What is the process for return or replacement of LTC1877EMS8#PBF?
All LTC1877EMS8#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC1877EMS8#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 LTC1877EMS8#PBF part is unused and in its original packaging.
Return procedure for LTC1877EMS8#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC1877EMS8#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…
