My Inquiry
My Account
Analog Devices Inc. LT1512CS8#PBF
- Part No.:
- LT1512CS8#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Battery Chargers
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LT1512CS8#PBF.pdf
- Description:
- IC BATT CHG MULT-CHEM 1CEL 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:986
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT1512CS8#PBF from Analog Devices (formerly Linear Technology) is a 500kHz current-mode switching regulator IC optimized for constant-current/constant-voltage battery charging in SEPIC or flyback topologies. It features 1.5A maximum switch current, 1% voltage accuracy, 100mV current sense threshold, and ground-referred current sensing - enabling single-cell Li-ion charging with input voltage below, equal to, or above battery voltage.
For engineers reviewing the LT1512CS8#PBF datasheet, LT1512CS8#PBF pinout, LT1512CS8#PBF application, or LT1512CS8#PBF equivalent, key selection criteria include its dual feedback architecture (FB + IFB), thermal-limited 1A max charge current capability, S/S pin dual-function (shutdown/synchronization), VC pin for loop compensation and soft-start, and SO-8 package suitability for compact battery charger designs.
Technical Context
The LT1512CS8#PBF implements current-mode control with two independent feedback paths: FB senses output voltage via a resistive divider referenced to a 1.245V internal bandgap, while IFB senses charging current via a –100mV regulated reference across an external sense resistor. Its integrated 40V breakdown NPN switch and adaptive anti-saturation driver enable efficient operation across wide VIN–VBAT differentials.
Operation relies on a fixed 500kHz oscillator driving a logic-controlled power switch, where duty cycle is terminated when sensed switch current reaches a level set by the VC pin voltage (1V–1.9V range). The separate GND and GND S pins isolate high-di/dt switch return paths from precision analog ground, critical for stable current regulation in noisy battery systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | 500kHz typical; minimizes inductor size and enables compact SEPIC charger layouts. |
| Max Switch Current | 1.5A at 50% duty cycle; supports up to ~1A Li-ion charging current with thermal derating. |
| Voltage Reference Accuracy | ±1% over temperature; ensures precise 4.2V float voltage for single Li-ion cells. |
| Current Sense Threshold | –100mV at IFB pin; enables high-efficiency, ground-referenced current sensing without battery isolation. |
| Input Voltage Range | 2.7V to 30V; allows operation with wall adapters, USB, or automotive sources - even when VIN < VBAT. |
| Thermal Resistance (θJA) | 130°C/W (SO-8 package); requires PCB copper area planning to maintain TJ ≤ 125°C at full load. |
| Shutdown Supply Current | 12µA typical; preserves battery life during idle or system sleep modes. |
Pinout & Package
LT1512CS8#PBF is housed in an 8-lead plastic SO (SO-8) surface-mount package with exposed pad not specified in source data. Pin functions are validated per Linear Technology's official pin configuration diagram and functional descriptions.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VC | Error amplifier output / compensation node | Sets peak switch current (0–1.8A) and enables frequency compensation, soft-start, and current limiting via external RC network to GND S. |
| FB | Voltage feedback input | Inverting input of voltage error amplifier; regulates output voltage by comparing divider voltage to 1.245V internal reference. |
| IFB | Current feedback input | Inverting input of current sense amplifier; regulates charging current by servoing external sense resistor voltage to –100mV. |
| S/S | Shutdown/synchronization input | Logic-compatible pin: low = shutdown (12µA IQ); 600–800kHz AC signal = synchronization; floating = enabled. |
| VSW | Internal switch collector | Carries up to 1.5A pulsed current; requires short, low-inductance PCB trace to minimize EMI and voltage spikes. |
| GND | Power ground | Return path for switch current; must connect directly to ground plane near IC, separate from GND S. |
| GND S | Signal ground | Return for FB, IFB, VC, and S/S circuits; isolates analog ground from switch noise to preserve regulation accuracy. |
| VIN | Input supply | Accepts 2.7–30V; powers internal 2.3V LDO and oscillator; requires local low-ESR bypass capacitor. |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent feedback loops | Simultaneous regulation of battery voltage (via FB) and charging current (via IFB) enables true CC/CV charging without external controllers. |
| Ground-referenced current sensing | IFB pin regulates at –100mV, eliminating need for high-side current sense amplifiers or isolated sense paths - simplifies layout and reduces BOM cost. |
| SEPIC topology optimization | Supports charging when input voltage is lower than battery voltage (e.g., 5V USB → 4.2V Li-ion), with no reverse discharge path when disabled. |
| Integrated anti-saturation driver | Adaptive logic detects switch saturation onset and adjusts drive current dynamically, minimizing turn-off delay and reducing switching losses. |
| Separate power and signal grounds | GND and GND S pins physically isolate high-di/dt switch return from sensitive analog circuitry, preventing ground bounce from degrading current regulation accuracy. |
Applications
| Portable Medical Device Charging | Industrial Handheld Instrument Power |
|---|---|
Use Scenario: Rechargeable Li-ion battery in portable ECG monitor powered from USB or 12V adapter. IC Role / Device Role / Timing Role: Constant-current/constant-voltage charger controller managing full-charge cycle with precise 4.2V termination and 0.5A–1A programmable current. Use Value: Enables single-chip charging solution with input voltage flexibility (5V USB or 12V field supply), ground-referenced sensing for clean signal integrity, and <1% voltage accuracy meeting medical battery safety standards. | Use Scenario: Battery-backed data logger operating in remote industrial sites with variable 9–24V DC input. IC Role / Device Role / Timing Role: SEPIC-based charger IC delivering regulated 8.4V (2S Li-ion) output while accepting input down to 9V - below battery voltage. Use Value: Eliminates need for boost pre-regulator; allows direct use of unregulated plant power supplies; separate GND/GND S pins prevent sensor measurement errors caused by switch noise coupling. |
| Automotive Accessory Charger | Smart Lock Backup Power Management |
Use Scenario: In-vehicle Bluetooth tracker with Li-ion backup, charged from 12V car battery subject to cold-crank dips. IC Role / Device Role / Timing Role: Robust battery charger maintaining CC/CV profile across 6–16V input range, including start-stop transients. Use Value: 2.7V minimum input ensures operation during cranking; 40V switch rating withstands load-dump spikes; shutdown mode draws only 12µA to extend backup runtime. | Use Scenario: Smart door lock using primary alkaline cells with Li-ion backup, requiring low-quiescent charging when main power is available. IC Role / Device Role / Timing Role: Precision current-limited charger that activates only when wall adapter is connected, with programmable current via PWM input. Use Value: PWM-programmable charging (Figure 5) enables firmware-controlled current scaling; 100mV IFB threshold minimizes sense resistor power loss; shutdown current <15µA preserves primary cell life during long standby. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar battery charger controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC4000 | Multi-chemistry, programmable CC/CV controller with I²C interface; requires external MOSFETs; higher integration but larger footprint. | Supports Li-ion, LiFePO₄, NiCd, Pb-acid with chemistry-specific profiles; suited for complex, microcontroller-managed systems. | Choose LTC4000 when digital control, multi-battery support, or telemetry is required - not for simple, cost-sensitive, analog-only SEPIC chargers. |
| MAX1771 | Legacy 300kHz current-mode controller; no integrated switch; requires external N-channel MOSFET and gate driver; 1% voltage ref, but no dedicated IFB pin. | Relies on external current sense amplifier and op-amp for CC regulation; less accurate and more complex layout than LT1512CS8#PBF's integrated dual-loop design. | Consider MAX1771 only if legacy design reuse or specific MOSFET selection mandates external switch - otherwise LT1512CS8#PBF offers superior integration and accuracy. |
Compared with LTC4000 and MAX1771, LT1512CS8#PBF delivers a self-contained, analog CC/CV solution in SO-8 with minimal external components, ideal for space-constrained, cost-sensitive, single-chemistry Li-ion chargers where simplicity and proven reliability outweigh digital configurability or multi-chemistry flexibility.
Availability
LT1512CS8#PBF is available at Aetrix Electronics and suitable for portable medical devices, industrial handheld instruments, automotive accessories, smart lock systems, and battery-powered IoT edge nodes requiring stable component supply and long-term manufacturability.
Supply support for LT1512CS8#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 all Linear parts, including the LT1512 series.
The LT1512CS8#PBF belongs to Linear's precision battery charger controller product line, designed specifically for analog, topology-optimized CC/CV charging in SEPIC/flyback configurations - targeting applications where input voltage may fall below battery voltage and ground-referenced current sensing is essential.
FAQ
What is the maximum battery voltage supported by the LT1512CS8#PBF?
The LT1512CS8#PBF itself does not impose a direct battery voltage limit; instead, maximum VBAT is constrained by the SEPIC topology's switch voltage rating: VSW ≤ 40V, and VSW = VIN + VBAT. With VIN ≤ 30V, this yields VBAT ≤ 40V – VIN. For example, at VIN = 12V, VBAT may reach up to 28V - sufficient for up to 7-series Li-ion (29.4V) or 2-series LiFePO₄ (7.2V). Always verify worst-case VSW in layout.
Can the LT1512CS8#PBF be used with lead-acid batteries?
Yes, the LT1512CS8#PBF supports lead-acid charging via its programmable CC/CV architecture. Set the FB divider for 2.3–2.45V/cell (e.g., 13.8V for 6-cell) and adjust R3 to achieve desired bulk current (e.g., C/10). Its 1% voltage accuracy and ground-referenced IFB sensing ensure reliable absorption and float stage control without requiring high-side sensing or additional ICs.
How does the S/S pin function in synchronization mode for the LT1512CS8#PBF?
In synchronization mode, the S/S pin accepts a 600–800kHz square wave (≥0.5VPP) to lock the LT1512CS8#PBF's internal 500kHz oscillator. Unlike shutdown, this mode keeps the IC fully operational - the internal timer prevents false shutdown during sync signal transitions. This reduces EMI by aligning switching edges with other system clocks and avoids beat frequencies in multi-rail power systems.
Why does the LT1512CS8#PBF use separate GND and GND S pins?
The LT1512CS8#PBF uses separate GND (power ground) and GND S (signal ground) pins to prevent fast-switching currents from modulating the reference and feedback nodes. High-di/dt return paths through GND can induce millivolt-level noise on shared ground traces, corrupting the 1.245V reference and –100mV IFB threshold. Routing analog components (R1/R2, R4/C4, compensation network) exclusively to GND S ensures stable CC/CV regulation under dynamic load conditions.
What is the role of the VC pin in LT1512CS8#PBF current limiting?
The VC pin sets the peak switch current threshold linearly: 1V ≈ 0A, 1.9V ≈ 1.8A. During constant-current operation, the error amplifier drives VC to maintain –100mV at IFB; thus, VC voltage reflects real-time charge current demand. External RC networks on VC provide loop compensation, while clamping VC below 0.8V forces zero duty cycle - enabling soft-start and overcurrent foldback protection in the LT1512CS8#PBF.
LT1512CS8#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Battery Chemistry:
- Multi-Chemistry
- Number of Cells:
- 1
- Current - Charging:
- Constant - Programmable
- Programmable Features:
- -
- Fault Protection:
- -
- Charge Current - Max:
- 1A
- Battery Pack Voltage:
- -
- Voltage - Supply (Max):
- 25V
- Interface:
- -
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SO
LT1512CS8#PBF FAQ
1.How can I place an order for LT1512CS8#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT1512CS8#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 LT1512CS8#PBF reliable?
The price and inventory of LT1512CS8#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT1512CS8#PBF is usually 5 days.
3.What payment methods are accepted for LT1512CS8#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT1512CS8#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT1512CS8#PBF?
LT1512CS8#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT1512CS8#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 LT1512CS8#PBF?
For technical support, including LT1512CS8#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT1512CS8#PBF requirements.
6.How does Aetrix verify that LT1512CS8#PBF is sourced from the original manufacturer or authorized distributors?
All LT1512CS8#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 LT1512CS8#PBF meets industry standards.
7.What is the process for return or replacement of LT1512CS8#PBF?
All LT1512CS8#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LT1512CS8#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 LT1512CS8#PBF part is unused and in its original packaging.
Return procedure for LT1512CS8#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT1512CS8#PBF Tags
-
BQ21040DBVR
Texas Instruments
-
MCP73812T-420I/OT
Microchip Technology
-
MCP73831T-2ACI/OT
Microchip Technology
-
MCP73832T-2ACI/OT
Microchip Technology
-
MCP73831T-2DCI/OT
Microchip Technology
-
MCP73832T-2DCI/OT
Microchip Technology
-
MCP73831T-2ATI/OT
Microchip Technology
-
MCP73832T-2ATI/OT
Microchip Technology
-
MCP73831T-5ACI/OT
Microchip Technology
-
MCP73832T-2ACI/MC
Microchip Technology
-
MCP73831T-2ACI/MC
Microchip Technology
-
MCP73831T-2ATI/MC
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…
