My Inquiry
My Account
Analog Devices Inc. LTC2928IUHF#PBF
- Part No.:
- LTC2928IUHF#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Supervisors
- Package:
- 38-WFQFN Exposed Pad
- Datasheet:
-
LTC2928IUHF#PBF.pdf
- Description:
- IC SUPERVISOR 4 CHANNEL 38QFN
- Quantity:
- Payment:
- Shipping:
Inventory:499
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC2928IUHF#PBF from Analog Devices (formerly Linear Technology) is a four-channel cascadable power supply sequencer and high-accuracy supervisor IC. It performs staged enable/disable sequencing of up to four supplies per device, provides 1.5% undervoltage monitoring accuracy across V1–V4 inputs, supports cascaded configurations for unlimited supply control, and integrates charge-pumped EN outputs (VCC + 5.5V) for driving N-channel MOSFETs - used in telecom infrastructure power management systems.
For engineers reviewing the LTC2928IUHF#PBF datasheet, LTC2928IUHF#PBF pinout, LTC2928IUHF#PBF application, or LTC2928IUHF#PBF equivalent, key selection considerations include its –40°C to +85°C industrial temperature range, 38-lead 5mm × 7mm QFN package, configurable sequence timing via RT/STMR/PTMR/RTMR pins, and fault-diagnostic reporting via CMP/FLT pins.
Technical Context
The LTC2928IUHF#PBF implements a state-machine-based sequencing engine with independent time-position decoding per channel (RT1–RT4), dual-phase operation (sequence-up and sequence-down), and integrated timers: STMR sets inter-supply delay (8.67 ms/µF), PTMR enforces power-good timeout (4 ms/µF), and RTMR configures reset assertion delay (4 ms/µF). All comparators operate with ±18 mV threshold accuracy over temperature.
It features a high-voltage input (HVCC: 7.2–16.5 V) with internal 3.3 V regulator for VCC, buffered REF output for negative supply monitoring, and OVA-biased overvoltage detection. Fault management includes latchable CMP outputs, FLT-driven system shutdown, and MS1/MS2-configurable RST–FLT coupling and debug modes.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC Range | 2.9 V to 6 V - powers core logic; regulated from HVCC when used. |
| HVCC Range | 7.2 V to 16.5 V - enables direct connection to 12 V rails without external regulators. |
| Undervoltage Accuracy | ±1.5% - ensures reliable reset assertion across V1–V4 at 0.5 V nominal threshold. |
| EN Output Voltage | VCC + 5.5 V (typ.) - sufficient gate drive for standard N-channel MOSFETs without level shifters. |
| Operating Temp | –40°C to +85°C - qualified for industrial and telecom infrastructure environments. |
| Package | 38-lead 5 mm × 7 mm QFN - exposes thermal pad for enhanced power dissipation (θJA = 34°C/W). |
| Sequence Channels | 4 independent - each with configurable time position, UV/OV thresholds, and enable polarity. |
Pinout & Package
Package: 38-lead plastic QFN (5 mm × 7 mm), exposed thermal pad (pin 39), RoHS-compliant, lead-free finish (PBF).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| EN1–EN4 | Charge-pumped enable outputs | Drive N-channel MOSFET gates at VCC + 5.5 V; sink 2.5 mA low; support external pass-FET control. |
| V1–V4 | High-impedance voltage monitor inputs | Accept resistor-divided supply voltages; support 3 positive + 1 negative (V1 w/ REF) configuration when VSEL = VCC. |
| RT1–RT4 | Time-position configuration inputs | Each connects to VCC via resistor to select one of eight sequence positions (0–7); ground disables channel. |
| CAS | Cascade input/output | Chains multiple LTC2928s; master pulls CAS high after ON edge; slaves trigger next time position on CAS rising edge. |
| FLT | Fault status I/O | Pulled low on internal/external fault (OV, UV timeout, command error); latches until all supplies return below sequence-down thresholds. |
| CMP1–CMP4 | Comparator status outputs | Indicate per-channel UV condition during monitoring phase; latch during fault for diagnostic readout. |
| RST | Microprocessor reset output | Pulls low if any monitored supply falls below UV threshold; asserts high only after all supplies remain above threshold for RTMR delay. |
| REF | Buffered reference output | Provides 1.189 V (typ.) reference for negative supply monitoring on V1; sources 1 mA, sinks 200 µA. |
| STMR/PTMR/RTMR | Capacitor-timed control inputs | Set sequence delay (8.67 ms/µF), power-good timeout (4 ms/µF), and reset delay (4 ms/µF) using external capacitors to GND. |
Key Features
| Feature | Design Value |
|---|---|
| Cascadable 4-channel sequencing | Unlimited supply count via CAS chaining; no software or PCB changes required for scaling. |
| 1.5% UV monitor accuracy | Guaranteed over –40°C to +85°C; eliminates need for calibration in precision power-rail supervision. |
| VCC + 5.5 V charge-pumped EN outputs | Directly drives standard N-channel MOSFETs without external gate drivers or level shifters. |
| Fault diagnostics with latchable CMP outputs | Identifies exact failing channel and fault type (UV, OV, timeout, command) without external logic. |
| Configurable sequence-up/down thresholds | SQT1/SQT2 select 10%/33%/67%/100% of threshold - supports asymmetric ramp-up/ramp-down profiles. |
| High-voltage HVCC input (up to 16.5 V) | Enables single-supply operation from 12 V backplanes; internal regulator delivers stable 3.3 V to VCC. |
Applications
| Telecom Power Sequencing | Multi-Rail FPGA/ASIC Power Management |
|---|---|
|
Use Scenario: Sequencing 12 V, 3.3 V, 2.5 V, and 1.2 V rails in 5G base station line cards with strict ramp-order and hold-time requirements. IC Role / Device Role / Timing Role: LTC2928IUHF#PBF acts as primary sequencer and supervisor, enforcing staggered enable timing via RT1–RT4 resistors and verifying rail stability before releasing RST. Use Value: Eliminates manual firmware sequencing delays and prevents FPGA configuration failure due to out-of-spec supply sequencing. |
Use Scenario: Managing core, I/O, auxiliary, and PLL voltage rails for high-end FPGAs requiring precise power-up order and margin testing capability. IC Role / Device Role / Timing Role: LTC2928IUHF#PBF controls EN outputs to enable/disable rails, uses RDIS to force RST high during voltage margining, and reports faults via CMP/FLT for debug. Use Value: Enables production-level voltage margin testing without modifying board layout or adding test points. |
| Industrial PLC Power Architecture | Redundant Server PSU Control |
|
Use Scenario: Supervising isolated 24 V, 5 V, 3.3 V, and analog sensor rails in programmable logic controllers operating in harsh ambient conditions. IC Role / Device Role / Timing Role: LTC2928IUHF#PBF monitors all rails with ±1.5% accuracy, triggers system-wide shutdown on FLT, and maintains operation down to –40°C. Use Value: Ensures deterministic power-fail response and meets IEC 61000-4 immunity requirements via hardware-based supervision. |
Use Scenario: Coordinating startup/shutdown of dual hot-swap PSUs in enterprise servers, including graceful power-down on PSU failure. IC Role / Device Role / Timing Role: LTC2928IUHF#PBF sequences primary and backup PSUs, uses CAS to synchronize enable timing, and asserts FLT to disable failed unit while maintaining load. Use Value: Achieves zero-downtime failover by isolating faulty PSU without disrupting downstream loads. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar power supply sequencing and supervision applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS65400PWPR | Integrated quad-buck controller + sequencer; no HVCC input; max VCC = 5.5 V; lower UV accuracy (±2.5%). | Best for compact, cost-sensitive designs where DC/DC regulation and sequencing are co-located on same die. | Choose TPS65400PWPR when integrating regulation and sequencing saves board space, but avoid if HVCC > 6 V or ±1.5% UV accuracy is mandatory. |
| ADM1166ACPZ | 12-channel PMBus-configurable sequencer/supervisor; requires I²C host; supports digital margining; no charge-pump EN outputs. | Preferred for systems needing remote configuration, telemetry, and dynamic reprogramming of sequencing profiles. | Choose ADM1166ACPZ when firmware-controlled flexibility and telemetry outweigh need for autonomous, pin-strapped operation. |
Compared with TPS65400PWPR and ADM1166ACPZ, the LTC2928IUHF#PBF offers superior analog accuracy, autonomous operation without microcontroller dependency, and native high-voltage interface - making it optimal for robust, standalone, high-reliability power sequencing in industrial and telecom equipment.
Availability
LTC2928IUHF#PBF is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLCs, and FPGA/ASIC power management requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.
Supply support for LTC2928IUHF#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 product support, documentation, and manufacturing continuity for the LTC portfolio.
The LTC2928IUHF#PBF belongs to Linear's precision power management IC family, designed specifically for autonomous, high-accuracy sequencing and supervision of multi-rail systems in mission-critical infrastructure.
FAQ
What is the maximum number of power supplies that can be sequenced using LTC2928IUHF#PBF?
The LTC2928IUHF#PBF supports unlimited supply sequencing through cascading: a single device controls up to four supplies, and multiple LTC2928IUHF#PBF units connect via the CAS pin to extend sequencing capacity across arbitrary numbers of rails without software or layout changes.
Does LTC2928IUHF#PBF support negative voltage monitoring?
Yes - the LTC2928IUHF#PBF supports one negative supply monitoring channel on V1 when VSEL is tied to VCC; the buffered REF output (1.189 V) serves as the reference for the V1 divider, enabling accurate supervision of –1.2 V, –2.5 V, or –3.3 V rails.
What is the purpose of the RDIS pin on LTC2928IUHF#PBF?
The RDIS pin on LTC2928IUHF#PBF forces the RST output high regardless of supply conditions - enabling voltage margin testing by holding the system in reset while adjusting rail voltages, then releasing RST to verify functional behavior at boundary limits.
Can LTC2928IUHF#PBF drive N-channel MOSFETs directly?
Yes - the LTC2928IUHF#PBF integrates a charge pump that delivers EN1–EN4 outputs at VCC + 5.5 V (typ.), providing sufficient gate-source voltage to fully enhance standard N-channel MOSFETs used as high-side pass devices without external level shifters or drivers.
How does fault reporting work on LTC2928IUHF#PBF?
Fault reporting on LTC2928IUHF#PBF uses latched CMP1–CMP4 outputs: during a fault (UV timeout, OV, command error), each comparator holds its state indicating which supply failed and whether it was undervoltage or overvoltage; FLT pulls low to initiate system shutdown, and status remains readable until cleared via return-to-zero sequence.
LTC2928IUHF#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 38-WFQFN Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Sequencer
- Number of Voltages Monitored:
- 4
- Voltage - Threshold:
- Adjustable/Selectable
- Output:
- -
- Reset:
- Active Low
- Reset Timeout:
- 5ms Minimum
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 38-QFN (5x7)
LTC2928IUHF#PBF FAQ
1.How can I place an order for LTC2928IUHF#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC2928IUHF#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 LTC2928IUHF#PBF reliable?
The price and inventory of LTC2928IUHF#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC2928IUHF#PBF is usually 5 days.
3.What payment methods are accepted for LTC2928IUHF#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC2928IUHF#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC2928IUHF#PBF?
LTC2928IUHF#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC2928IUHF#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 LTC2928IUHF#PBF?
For technical support, including LTC2928IUHF#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC2928IUHF#PBF requirements.
6.How does Aetrix verify that LTC2928IUHF#PBF is sourced from the original manufacturer or authorized distributors?
All LTC2928IUHF#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 LTC2928IUHF#PBF meets industry standards.
7.What is the process for return or replacement of LTC2928IUHF#PBF?
All LTC2928IUHF#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC2928IUHF#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 LTC2928IUHF#PBF part is unused and in its original packaging.
Return procedure for LTC2928IUHF#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC2928IUHF#PBF Tags
-
MIC826SYMT-TR
Microchip Technology
-
APX803S-31SA-7
Diodes Incorporated
-
APX803L20-29SA-7
Diodes Incorporated
-
TPS3828-33DBVR
Texas Instruments
-
V6340RSP3B+
EM Microelectronic
-
EM6325CXSP5B-2.9+
EM Microelectronic
-
MCP120T-300I/TT
Microchip Technology
-
MCP130T-315I/TT
Microchip Technology
-
MCP120T-475I/TT
Microchip Technology
-
MCP111T-300E/TT
Microchip Technology
-
MCP120T-315I/TT
Microchip Technology
-
MCP809T-315I/TT
Microchip Technology
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…
