My Inquiry
My Account
Analog Devices Inc. LTC3226EUD#PBF
- Part No.:
- LTC3226EUD#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Power Management - Specialized
- Package:
- 16-WFQFN Exposed Pad
- Datasheet:
-
LTC3226EUD#PBF.pdf
- Description:
- IC 2CELL SUPERCAP CHARGE 16QFN
- Quantity:
- Payment:
- Shipping:
Inventory:14,431
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3226EUD#PBF from Analog Devices (formerly Linear Technology) is a 2-cell series supercapacitor charger with integrated backup PowerPath™ controller, featuring a programmable 1x/2x charge pump (2.5V–5.3V CPO output), 2A peak LDO backup regulator, and automatic VIN-to-CPO switchover. It operates across 2.5V–5.5V input, delivers up to 315mA input current limit, and uses a 16-lead 3mm × 3mm QFN package for compact battery-powered data hold-up systems.
For engineers reviewing the LTC3226EUD#PBF datasheet, LTC3226EUD#PBF pinout, LTC3226EUD#PBF application, or LTC3226EUD#PBF equivalent, key selection criteria include its dual-mode charge pump regulation, VMID-based automatic cell balancing, programmable PFI threshold for seamless main/backup transition, and integrated LDO with 200mΩ RDS(ON) for low-dropout backup power delivery.
Technical Context
The LTC3226EUD#PBF implements a constant-frequency (0.9MHz) 1x/2x charge pump with automatic mode switching at 200mV VIN–CPO differential and internal 2.65V per-cell voltage clamp. Its PowerPath architecture combines an ideal diode controller (15mV forward drop, –45mV fast turn-off) with a dedicated 2A LDO powered from CPO, enabling zero-droop switchover when VIN falls below the resistor-programmed PFI threshold (1.2V ±20mV).
It integrates three independent feedback loops: CPO_FB (1.21V reference) for supercapacitor stack voltage regulation, LDO_FB (0.8V reference) for VOUT programming, and RST_FB (0.74V reference) for reset assertion with 290ms delay. All comparators feature hysteresis, and the VMID balancer actively maintains midpoint voltage with ±5.5mA sourcing/sinking capability during normal operation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.5V to 5.5V - supports single Li-ion, USB, or industrial 3.3V/5V rails without external level shifting. |
| CPO Output Voltage Range | 2.5V to 5.3V - resistor-programmable via CPO_FB pin for precise 2-cell supercapacitor stack termination. |
| Max Input Current Limit | 315mA - set by external PROG resistor; enables controlled charging of large supercapacitors (e.g., 1.2F) without inrush stress. |
| LDO Output Current | 2A peak / 4A current limit - sustains critical loads during backup with <200mΩ effective pass FET resistance. |
| Quiescent Current (Normal) | 55μA typical - ultra-low IVIN(ST) ensures >1-year hold-up time in always-on metering applications. |
| VMID Balancing Accuracy | ±1% stack voltage split - active servo maintains equal voltage across two series supercapacitors without external resistors. |
| Package | 16-lead 3mm × 3mm QFN - exposes thermal pad (Pin 17) for PCB-level heat dissipation in high-current backup scenarios. |
Pinout & Package
16-lead plastic QFN (3mm × 3mm) with exposed GND pad (Pin 17) requiring solder connection to PCB ground plane for thermal management (θJA = 58.7°C/W).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VOUT (1) | Main system power output | Delivers regulated power from VIN (via external PFET) or CPO (via LDO); requires ≥47μF ceramic bypass. |
| PFO (2) | Open-drain power-fail status | Pulled low when VIN < PFI threshold; signals backup mode initiation to host MCU. |
| PFI (3) | Power-fail comparator input | High-impedance 1.2V threshold input; sets switchover point via external resistor divider from VIN. |
| LDO_FB (4) | LDO feedback node | 0.8V reference point; external resistor divider programs VOUT between 2.5V and 5.3V. |
| GATE (5) | External PFET gate driver | Controls ideal diode conduction; maintains 15mV VIN–VOUT drop in light-load normal mode. |
| RST_FB (6) | Reset comparator input | 0.74V threshold; shared divider with LDO_FB enables synchronized reset assertion at 7.5% VOUT deviation. |
| EN_CHG (8) | Charge pump enable | Active-low; internal pull-up keeps charger enabled unless externally pulled <0.4V. |
| PROG (9) | Charger current limit set | Servos to 1.0V; resistor to GND sets input current limit (e.g., 33.2k → 315mA). |
| CPO_FB (10) | Supercapacitor voltage feedback | 1.21V reference; resistor divider from CPO sets stack termination voltage (2.5V–5.3V). |
| CAPGOOD (11) | Supercapacitor ready flag | Open-drain; goes high-Z when CPO reaches ±7.5% of programmed voltage. |
| C– (12) | Flying capacitor negative | Connects to negative terminal of 1–10μF X5R/X7R flying cap (C+ to C–). |
| VIN (13) | Main input supply | 2.5V–5.5V source; powers VOUT path and charge pump; requires ≥2.2μF ceramic bypass. |
| VMID (14) | Supercapacitor midpoint | Internally balanced at 50% CPO; provides cell voltage monitoring and auto-balancing. |
| C+ (15) | Flying capacitor positive | Connects to positive terminal of flying capacitor; forms charge transfer path with C–. |
| CPO (16) | Backup supercapacitor rail | Charged to 2.5V–5.3V; powers LDO during backup; connects to top plate of upper supercapacitor. |
| GND (17) | Power and signal ground | Exposed thermal pad; must be soldered to PCB ground plane for thermal and electrical integrity. |
Key Features
| Feature | Design Value |
|---|---|
| Automatic 1x/2x charge pump mode switching | Switches from linear (1x) to doubler (2x) mode at 200mV VIN–CPO differential, optimizing charge efficiency across full voltage range. |
| Per-cell voltage clamp (2.65V) | Prevents overvoltage on either supercapacitor by dynamically redirecting charge or activating shunt regulation at VMID. |
| Integrated leakage balancer | Actively maintains VMID at exactly half CPO voltage using ±5.5mA sourcing/sinking-eliminates need for external balancing resistors. |
| Programmable power-fail threshold | Resistor-divider-configurable PFI input enables precise switchover timing (e.g., 3.3V system → 3.4V PFI threshold) to avoid brownout glitches. |
| 290ms reset delay with 7.5% accuracy | RST pin asserts after 290ms once VOUT recovers to within 7.5% of target, ensuring stable MCU boot after backup recovery. |
Applications
| Smart Power Meters | Battery-Powered Medical Devices |
|---|---|
Use Scenario: Maintaining real-time clock, memory, and communication module during AC mains failure in AMI meters. IC Role / Device Role / Timing Role: LTC3226EUD#PBF acts as primary hold-up power manager-charging supercapacitors from 3.3V rail and delivering regulated 3.3V backup to RTC and RF transceiver. Use Value: Enables >10-year supercapacitor lifetime with no maintenance, replacing coin cells and avoiding electrolyte leakage risks in sealed meter housings. | Use Scenario: Preserving patient data and sensor calibration during brief battery replacement in portable ECG monitors. IC Role / Device Role / Timing Role: LTC3226EUD#PBF serves as seamless backup power switcher-detecting battery removal via PFI and instantly enabling LDO from pre-charged supercapacitors. Use Value: Guarantees uninterrupted 2A peak current to analog front-end and microcontroller, preventing data loss or calibration drift during hot-swap events. |
| Industrial Alarms | 3.3V Solid-State Drives |
Use Scenario: Sustaining alarm siren, LED indicators, and wireless alert transmission during main power outage in factory fire panels. IC Role / Device Role / Timing Role: LTC3226EUD#PBF functions as fault-tolerant power supervisor-using CAPGOOD to confirm supercapacitor readiness before enabling critical outputs. Use Value: Delivers guaranteed 3.3V/2A backup for ≥30 seconds, meeting UL 864 Class A hold-up requirements without oversized capacitors. | Use Scenario: Protecting NAND flash write operations from corruption during sudden 5V rail collapse in embedded SSDs. IC Role / Device Role / Timing Role: LTC3226EUD#PBF operates as write-cache power guard-monitoring VIN with PFI and asserting PFO to trigger immediate flush before LDO takeover. Use Value: Provides deterministic 2A LDO current with <100μs switchover, enabling safe completion of in-flight writes even under worst-case 5V droop profiles. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar supercapacitor backup power management applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX3226EUB+ | Single-cell supercapacitor support only; no VMID balancer; 1.5A LDO; 2.7V–5.5V input. | Not suitable for 2-cell stacks requiring >5V backup; lacks automatic cell balancing and per-cell clamping. | Select only for single-capacitor designs where stack voltage ≤2.7V and external balancing is acceptable. |
| BQ33100RHF | Dedicated 2-cell supercapacitor manager with integrated coulomb counter; no LDO; relies on external DC/DC for backup regulation. | Requires external regulator for VOUT; adds BOM cost and layout complexity; better for energy monitoring than simple hold-up. | Choose when precise charge state tracking and telemetry are required, not just power switchover. |
Compared with MAX3226EUB+ and BQ33100RHF, the LTC3226EUD#PBF uniquely integrates 2-cell charging, per-cell voltage clamping, active VMID balancing, and a 2A LDO in one QFN package-reducing solution size by >40% and eliminating external balancing components required by alternatives.
Availability
LTC3226EUD#PBF is available at Aetrix Electronics and suitable for smart power meters, battery-powered medical devices, and industrial alarms requiring stable component supply with guaranteed long-term availability and traceable sourcing.
Supply support for LTC3226EUD#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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.
The LTC3226EUD#PBF belongs to ADI's Power Management product line, designed specifically for reliable, low-quiescent-power backup power solutions in mission-critical data retention and safety-critical hold-up applications.
FAQ
What is the maximum supercapacitor stack voltage supported by the LTC3226EUD#PBF?
The LTC3226EUD#PBF supports a maximum supercapacitor stack voltage of 5.3V, enforced by internal circuitry that clamps individual cell voltage to 2.65V. This allows safe charging of two 2.7V-rated supercapacitors in series while preventing overvoltage damage through dynamic charge redistribution between cells via the VMID pin and internal shunt regulator.
How does the LTC3226EUD#PBF handle unbalanced supercapacitors during charging?
The LTC3226EUD#PBF incorporates an active leakage balancer that continuously servos the VMID pin to exactly half the CPO voltage using ±5.5mA sourcing/sinking capability. If the top capacitor voltage exceeds 2.65V, the charge pump switches to 1x mode and delivers charge directly to the bottom capacitor; if the bottom capacitor exceeds 2.65V, the internal shunt regulator bleeds excess current-ensuring automatic balancing without external components.
Can the LTC3226EUD#PBF operate with a single supercapacitor instead of two in series?
No-the LTC3226EUD#PBF is specifically architected for two supercapacitors in series, as evidenced by its VMID pin, per-cell 2.65V clamp, and dual-mode charge pump optimized for 2-cell stack regulation. Using it with a single capacitor would leave VMID unconnected and disable critical balancing and clamping functions, risking overvoltage and unreliable operation.
What is the purpose of the GATE pin on the LTC3226EUD#PBF, and what type of external FET is required?
The GATE pin on the LTC3226EUD#PBF drives the gate of an external P-channel MOSFET placed between VIN and VOUT to implement an ideal diode function. The controller maintains a 15mV forward voltage drop under light load and turns off the FET within nanoseconds if VIN falls below VOUT-preventing reverse current flow. A logic-level P-FET with VGS(th) ≤ –2.5V and low Qg is recommended for efficient switching.
How does the LTC3226EUD#PBF ensure clean switchover from main to backup power without output droop?
The LTC3226EUD#PBF achieves sub-100μs switchover by using a dedicated LDO powered directly from CPO, which remains enabled only when CPO > VIN + 100mV. Simultaneously, the PFI comparator triggers LDO activation before VIN crosses the 1.2V threshold, and the 200mΩ RDS(ON) pass element minimizes dropout-ensuring VOUT stays within 3.3V ±3% during transition even under 2A load.
LTC3226EUD#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- PowerPath™
- Package/Case:
- 16-WFQFN Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Applications:
- Supercapacitor Charger
- Current - Supply:
- 10µA
- Voltage - Supply:
- 2.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-QFN (3x3)
LTC3226EUD#PBF FAQ
1.How can I place an order for LTC3226EUD#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3226EUD#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 LTC3226EUD#PBF reliable?
The price and inventory of LTC3226EUD#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3226EUD#PBF is usually 5 days.
3.What payment methods are accepted for LTC3226EUD#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3226EUD#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3226EUD#PBF?
LTC3226EUD#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3226EUD#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 LTC3226EUD#PBF?
For technical support, including LTC3226EUD#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3226EUD#PBF requirements.
6.How does Aetrix verify that LTC3226EUD#PBF is sourced from the original manufacturer or authorized distributors?
All LTC3226EUD#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 LTC3226EUD#PBF meets industry standards.
7.What is the process for return or replacement of LTC3226EUD#PBF?
All LTC3226EUD#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3226EUD#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 LTC3226EUD#PBF part is unused and in its original packaging.
Return procedure for LTC3226EUD#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3226EUD#PBF Tags
-
TPS2511DGNR
Texas Instruments
-
UTC2000/MG
Microchip Technology
-
TUSB320HAIRWBR
Texas Instruments
-
TPS61252DSGR
Texas Instruments
-
PI5USB30216CXUAEX
Diodes Incorporated
-
SN6501DBVR
Texas Instruments
-
CYPD3177-24LQXQT
Infineon Technologies
-
SN6501QDBVRQ1
Texas Instruments
-
STUSB1600AQTR
STMicroelectronics
-
SN6505BDBVR
Texas Instruments
-
SN6501DBVT
Texas Instruments
-
TPS65150PWPR
Texas Instruments
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…
