My Inquiry
My Account
Analog Devices Inc. LTC1550LCS8-2#TRPBF
- Part No.:
- LTC1550LCS8-2#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LTC1550LCS8-2#TRPBF.pdf
- Description:
- IC REG CHARGE PUMP -2V 20MA 8SO
- Quantity:
- Payment:
- Shipping:
Inventory:3,314
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC1550LCS8-2#TRPBF from Analog Devices (formerly Linear Technology) is a fixed-output, low-noise switched-capacitor voltage inverter with integrated linear post-regulator, delivering –2.0V ±2.5% at up to 20mA load current from a 2.7V–5.25V single supply. It features 900kHz charge pump frequency, <1mVP-P output ripple, and active-low TTL-compatible shutdown (SHDN). It is optimized for GaAs FET bias generation in portable RF transmitters.
For engineers reviewing the LTC1550LCS8-2#TRPBF datasheet, LTC1550LCS8-2#TRPBF pinout, LTC1550LCS8-2#TRPBF application, or LTC1550LCS8-2#TRPBF equivalent, key selection criteria include guaranteed –2V regulation over line/load/temperature, minimal external component count (4 capacitors), shutdown quiescent current <1µA, MSOP-8 package compatibility, and GaAs bias-specific noise performance.
Technical Context
The LTC1550LCS8-2#TRPBF integrates a 900kHz inverting charge pump stage followed by a negative linear regulator using an N-channel MOSFET pass device and internal 1.225V reference. Its feedback loop is optimized for fast transient response to suppress switching artifacts from CPOUT, enabling stable regulation under dynamic loads.
It operates exclusively in fixed –2V output mode with no ADJ pin; the REG pin provides open-drain power-good indication (active-low when |VOUT| within 5% of target). Shutdown control is active-low (SHDN), dropping supply current to 0.2µA typical while collapsing VOUT to 0V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | –2.0V ±2.5% over line, load, and temperature - ensures stable GaAs FET gate bias across operating conditions |
| Max Output Current | 20mA at VCC ≥ 3.75V - supports moderate-power RF transmitter stages without external boost |
| Output Ripple | <1mVP-P typical (with 10µF + 0.1µF output capacitor) - meets stringent noise requirements for sensitive RF bias rails |
| Supply Range | 2.7V to 5.25V - enables direct operation from Li-ion, 3.3V, or 5V system rails |
| Shutdown Current | 0.2µA typical - extends battery life in portable RF devices during idle periods |
| Oscillator Frequency | 900kHz - places switching energy outside critical 400–600kHz IF bands and minimizes capacitor size (0.1µF) |
| Regulation Accuracy | ±2.5% over full temperature range - eliminates need for external trimming in production |
Pinout & Package
Package: 8-lead MSOP (MS8), 3.0mm × 3.0mm × 0.85mm body, exposed pad optional, RoHS-compliant, tape-and-reel (#TRPBF).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (REG) | Open-drain power-good indicator | Pulls low when |VOUT| is within 5% of –2V; requires external pull-up to VCC or higher (≤6V); enables system-level power sequencing |
| 2 (CPOUT) | Negative charge pump output | Intermediate node supplying linear regulator input; requires 0.1µF ceramic capacitor to GND with star-ground connection to minimize ripple |
| 3 (GND) | Analog/power ground reference | Single ground pin for 8-lead MSOP; must connect to low-impedance ground plane to prevent regulation error and noise coupling |
| 4 (C1–) | Negative flying capacitor terminal | Completes charge transfer path with C1+; connects to 0.1µF flying capacitor (C1) - forms core of inverting charge pump |
| 5 (SHDN) | Active-low shutdown control | TTL-compatible input; pulled low to disable device (IQ ≈ 0.2µA); no internal pull-up - external resistor required for default-on operation |
| 6 (VCC) | Positive input supply | Accepts 2.7V–5.25V; requires ≥0.1µF bypass capacitor directly to GND; recommended 2.2µF ceramic for optimal ripple suppression |
| 7 (C1+) | Positive flying capacitor terminal | Drives 0.1µF flying capacitor (C1) in phase with internal 900kHz clock; high dv/dt node requiring short PCB traces |
| 8 (VOUT) | Regulated negative output | Delivers –2.0V; requires ≥4.7µF output capacitor (10µF recommended) with moderate ESR for loop stability and <1mVP-P ripple |
Key Features
| Feature | Design Value |
|---|---|
| Integrated linear post-regulator | Eliminates need for external LDO, reduces total solution size, and achieves <1mVP-P ripple without LC filtering |
| 900kHz charge pump frequency | Enables use of standard 0.1µF ceramic flying/output capacitors and avoids interference with common IF bands (400–600kHz) |
| Fixed –2V output with no external resistors | Simplifies BOM and layout; removes tuning uncertainty and resistor tolerance effects on bias voltage accuracy |
| Active-low TTL-compatible SHDN | Direct interface with microcontroller GPIOs or logic-level enable signals without level-shifting circuitry |
| Power-good (REG) output | Provides system-level fault detection and sequencing capability without adding discrete comparators or supervisors |
Applications
| GaAs FET Transmitter Bias | Negative Supply for RF Front-End ICs |
|---|---|
Use Scenario: Generating precise –2V gate bias for GaAs pHEMT power amplifiers in cellular handsets and portable radios. IC Role / Device Role / Timing Role: Primary regulated negative bias rail generator; replaces discrete charge pump + LDO solutions. Use Value: Delivers <1mVP-P ripple at 20mA, ensuring minimal AM-to-PM distortion and stable amplifier gain across battery discharge cycles. | Use Scenario: Providing clean –2V supply to analog front-end components such as RF mixers, VGA drivers, and IF amplifiers. IC Role / Device Role / Timing Role: Low-noise auxiliary negative rail source; synchronized via internal 900kHz oscillator to avoid beat frequencies with system clocks. Use Value: Enables high dynamic range signal processing by suppressing supply-induced noise floor elevation in sensitive receive paths. |
| Battery-Powered Portable Instruments | Low-Power Industrial Sensors |
Use Scenario: Powering dual-supply op-amps and precision ADCs in handheld test equipment powered by single-cell Li-ion batteries. IC Role / Device Role / Timing Role: Compact, low-quiescent-current negative rail generator supporting extended runtime and cold-temperature operation (–40°C to 85°C). Use Value: Maintains ±2.5% regulation across 2.7V–5.25V input range, eliminating need for input pre-regulation and reducing overall power loss. | Use Scenario: Supplying bias voltage to MEMS accelerometers, piezoelectric sensors, and low-noise instrumentation amplifiers in remote monitoring nodes. IC Role / Device Role / Timing Role: Ultra-low-noise, low-IQ negative supply source with shutdown control for duty-cycled sensing intervals. Use Value: Achieves 0.2µA shutdown current and <1mVP-P ripple, extending battery life while preserving sensor signal integrity and measurement resolution. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar negative voltage inverter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC1550LCS8-2.5#TRPBF | Fixed –2.5V output; identical pinout, package, and electrical specs except output voltage and minimum VCC (3.05V vs 2.7V) | Used where –2.5V bias is required for different GaAs FET threshold or alternate RF ICs | Select only if –2.5V output matches system-level bias requirement; not interchangeable with LTC1550LCS8-2#TRPBF due to voltage mismatch |
| LTC1551LCS8-2#TRPBF | Identical –2V output and performance, but features active-high SHDN (vs active-low) and no REG pin in 8-lead SO/MSOP packages | Suitable for systems where enable logic is active-high and power-good signaling is unnecessary | Choose when system control logic drives SHDN high to enable; verify absence of REG functionality does not impact power sequencing requirements |
Compared with LTC1550LCS8-2#TRPBF, LTC1550LCS8-2.5#TRPBF offers higher output voltage at the cost of reduced input headroom, while LTC1551LCS8-2#TRPBF swaps shutdown polarity and removes REG - making each alternative suitable only for specific control architecture or bias voltage needs, not drop-in replacements.
Availability
LTC1550LCS8-2#TRPBF is available at Aetrix Electronics and suitable for GaAs FET bias generation, portable RF front-end power, and battery-powered instrumentation requiring stable component supply, low-noise negative voltage, and compact MSOP-8 footprint.
Supply support for LTC1550LCS8-2#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 acquired Linear Technology in 2017 and maintains its precision analog and power management portfolio. Linear Technology was renowned for high-performance analog ICs with rigorous characterization and application-focused design.
The LTC1550L series belongs to Linear's regulated switched-capacitor inverter product line, engineered specifically for ultra-low-noise, low-component-count negative bias generation in portable RF and battery-constrained systems.
FAQ
What is the output voltage tolerance of the LTC1550LCS8-2#TRPBF over temperature and load?
The LTC1550LCS8-2#TRPBF delivers –2.0V with ±2.5% regulation over the full industrial temperature range (–40°C to 85°C), line (2.7V–5.25V), and load (0–20mA). This is guaranteed per the Electrical Characteristics table for the –2V variant, with tighter drift than unregulated charge pumps and sufficient accuracy for GaAs FET gate bias without trimming.
Can the LTC1550LCS8-2#TRPBF be used with a 2.5V input supply?
No - the LTC1550LCS8-2#TRPBF requires a minimum VCC of 2.7V for guaranteed –2V output regulation at any load. At 2.5V input, regulation fails and output collapses; the datasheet specifies 2.7V ≤ VCC ≤ 5.25V for the –2V version, with increasing minimum VCC for higher output magnitudes (e.g., 3.05V for –2.5V).
Does the LTC1550LCS8-2#TRPBF require external resistors to set the output voltage?
No - the LTC1550LCS8-2#TRPBF is a fixed-output variant with internal resistor divider; no external resistors are needed. Only adjustable versions (e.g., LTC1550LCMS8) use the ADJ pin and external R1/R2 network. The –2V version uses dedicated internal feedback to ensure accuracy and simplify layout.
What is the purpose of the REG pin on the LTC1550LCS8-2#TRPBF?
The REG pin on the LTC1550LCS8-2#TRPBF is an open-drain power-good indicator that pulls low when |VOUT| is within 5% of –2.0V. It sinks up to 4mA and requires an external pull-up (to VCC or ≤6V). This enables system-level power sequencing and fault detection without adding discrete supervision circuitry.
How many external capacitors does the LTC1550LCS8-2#TRPBF require for basic operation?
The LTC1550LCS8-2#TRPBF requires exactly four external capacitors: one 0.1µF flying capacitor (C1) between C1+ and C1–, one 0.1µF storage capacitor (CCP) from CPOUT to GND, one ≥2.2µF input bypass capacitor (CIN) from VCC to GND, and one ≥10µF output filter capacitor (COUT) from VOUT to GND - plus a 0.1µF ceramic in parallel for optimal ripple.
LTC1550LCS8-2#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Up/Step-Down
- Output Configuration:
- Negative
- Topology:
- Charge Pump
- Output Type:
- Fixed
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.7V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- -2V
- Voltage - Output (Max):
- -
- Current - Output:
- 20mA
- Frequency - Switching:
- 900kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SO
LTC1550LCS8-2#TRPBF FAQ
1.How can I place an order for LTC1550LCS8-2#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC1550LCS8-2#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 LTC1550LCS8-2#TRPBF reliable?
The price and inventory of LTC1550LCS8-2#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC1550LCS8-2#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC1550LCS8-2#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC1550LCS8-2#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC1550LCS8-2#TRPBF?
LTC1550LCS8-2#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC1550LCS8-2#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 LTC1550LCS8-2#TRPBF?
For technical support, including LTC1550LCS8-2#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC1550LCS8-2#TRPBF requirements.
6.How does Aetrix verify that LTC1550LCS8-2#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC1550LCS8-2#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 LTC1550LCS8-2#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC1550LCS8-2#TRPBF?
All LTC1550LCS8-2#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC1550LCS8-2#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 LTC1550LCS8-2#TRPBF part is unused and in its original packaging.
Return procedure for LTC1550LCS8-2#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC1550LCS8-2#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…
