LTC6813HLWE - 18-Cell Battery Stack Monitor, AEC-Q100 | ADI
MPN： LTC6813HLWE ✓ 啟用中LTC6813HLWE 概覽
A battery stack monitor is a mixed-signal IC that performs high-accuracy cell voltage, temperature, and current (via an external shunt) acquisition across long strings of series-stacked cells in Battery Management Systems (BMS). It belongs to the broader category of battery management ICs, which in turn sit under power management semiconductors. The LTC6813 family is the industry-standard cell monitor for mid- and high-voltage Li-ion packs in electric vehicles, stationary energy storage, and industrial backup systems.
Key features of this part include per-cell 2.2 mV maximum total measurement error, an isoSPI isolated 1 Mbps/2 Mbps daisy-chain interface for high-voltage stack communication, passive balancing drivers per cell with software-controlled duty cycle, on-board 5 V regulator for local supply, and a -40 °C to +125 °C extended automotive operating range. Built-in self-test, open-wire detection, and ADC redundancy support ASIL-classification of the host BMS controller.
Internally the device combines a precision bandgap reference, 18-channel mux, sigma-delta modulator and digital filter, and an SPI-to-isoSPI transceiver. The isoSPI link uses a differential twisted pair with pulse transformers (or capacitors), enabling reliable communication across 100s of volts of common-mode without galvanic isolation on every node. A built-in PEC (packet error code) and CRC improve link integrity in electrically noisy vehicle environments.
Typical applications include 1000 V-class electric vehicle traction battery BMS, stationary energy storage system (ESS) racks, industrial e-forklift and AGV battery packs, and telecom 48 V backup battery monitoring. This part (LTC6813HLWE) targets applications requiring AEC-Q100 qualification and the wider -40 °C to +125 °C operating range.
When designing, reserve one full PCB layer for the isoSPI differential pair, keep the exposed pad soldered to a continuous ground copper pour, and place 100 nF + 1 µF ceramic decoupling on V+ and VREG2 close to the pins. Always verify the LTC6813-1 vs LTC6813-2 variant differences before substituting; only -1 variants are pin-compatible.
直接替換替代品，適用於 LTC6813HLWE — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
LTC6813ILWE-1#PBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC6813HLWE-1#3ZZTRPBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC6813HLWE-1#PBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC6813HLWE 規格
| 功能 | 18-cell battery stack monitor |
| Measured Cells | Up to 18 series cells |
| Cell Measurement Error | < 2.2 mV total |
| Cell Input Voltage Range | 0 V to 5 V per cell |
| ADC Resolution | 16-bit sigma-delta |
| Communication Interface | SPI / isoSPI daisy chain (1 Mbps, 2 Mbps) |
| Cell Balancing | Passive balancing drivers per cell |
| 工作溫度範圍 | -40 °C to +125 °C |
| 封裝 | 64-LQFP-EP (LWE) 10x10 mm with exposed pad |
| 安裝類型 | Surface Mount |
| MSL 等級 | MSL3 (per JEDEC J-STD-020) |
| Automotive Qualification | AEC-Q100 Grade 1 (-40 °C to +125 °C) via #3ZZ suffix |
| RoHS 狀態 | Compliant |
LTC6813HLWE 腳位配置
| 腳位 1 | C0 — Cell 0 sense input (lowest cell in stack) |
| 腳位 2 | C1 — Cell 1 sense input |
| 腳位 3 | C2 — Cell 2 sense input |
| 腳位 4 | C3 — Cell 3 sense input |
| 腳位 5 | C4 — Cell 4 sense input |
| 腳位 6 | C5 — Cell 5 sense input |
| 腳位 7 | C6 — Cell 6 sense input |
| 腳位 8 | C7 — Cell 7 sense input |
| 腳位 9 | C8 — Cell 8 sense input |
| 腳位 10 | C9 — Cell 9 sense input |
| 腳位 11 | C10 — Cell 10 sense input |
| 腳位 12 | C11 — Cell 11 sense input |
| 腳位 13 | C12 — Cell 12 sense input |
| 腳位 14 | C13 — Cell 13 sense input |
| 腳位 15 | C14 — Cell 14 sense input |
| 腳位 16 | C15 — Cell 15 sense input |
| 腳位 17 | C16 — Cell 16 sense input |
| 腳位 18 | C17 — Cell 17 sense input |
| 腳位 19 | C18 — Cell 18 sense input (top of stack) |
| 腳位 20 | S1 — GPIO / balance switch output 1 |
| 腳位 21 | S2 — GPIO / balance switch output 2 |
| 腳位 22 | S3 — GPIO / balance switch output 3 |
| 腳位 23 | S4 — GPIO / balance switch output 4 |
| 腳位 24 | S5 — GPIO / balance switch output 5 |
| 腳位 25 | S6 — GPIO / balance switch output 6 |
| 腳位 26 | S7 — GPIO / balance switch output 7 |
| 腳位 27 | S8 — GPIO / balance switch output 8 |
| 腳位 28 | S9 — GPIO / balance switch output 9 |
| 腳位 29 | S10 — GPIO / balance switch output 10 |
| 腳位 30 | S11 — GPIO / balance switch output 11 |
| 腳位 31 | S12 — GPIO / balance switch output 12 |
| 腳位 32 | S13 — GPIO / balance switch output 13 |
| 腳位 33 | S14 — GPIO / balance switch output 14 |
| 腳位 34 | S15 — GPIO / balance switch output 15 |
| 腳位 35 | S16 — GPIO / balance switch output 16 |
| 腳位 36 | S17 — GPIO / balance switch output 17 |
| 腳位 37 | S18 — GPIO / balance switch output 18 |
| 腳位 38 | GND — Ground reference for VREG2 |
| 腳位 39 | VREG2 — 5V LDO output for internal logic |
| 腳位 40 | V+ — Top-of-stack supply input (cell 18 node) |
| 腳位 41 | VREG — Linear regulator output for ADC analog supply |
| 腳位 42 | REF — Buffered reference output (decouple 100nF) |
| 腳位 43 | TOS — Top of stack sense (redundant C18 sense) |
| 腳位 44 | GPIO1 — General-purpose I/O / analog input |
| 腳位 45 | GPIO2 — General-purpose I/O / analog input |
| 腳位 46 | GPIO3 — General-purpose I/O / analog input |
| 腳位 47 | GPIO4 — General-purpose I/O / analog input |
| 腳位 48 | GPIO5 — General-purpose I/O / analog input |
| 腳位 49 | WDT — Watchdog timer input |
| 腳位 50 | MISO — SPI master-in slave-out (legacy SPI mode) |
| 腳位 51 | MOSI — SPI master-out slave-in (legacy SPI mode) |
| 腳位 52 | SCK — SPI clock (legacy SPI mode) |
| 腳位 53 | CSB — SPI chip-select (legacy SPI mode) |
| 腳位 54 | IP — isoSPI positive differential port |
| 腳位 55 | IM — isoSPI negative differential port |
| 腳位 56 | IBIAS — isoSPI bias resistor pin |
| 腳位 57 | DRIVE — isoSPI drive level select |
| 腳位 58 | RESETB — Active-low reset input |
| 腳位 59 | THERM — On-die temperature monitor / thermal output |
| 腳位 60 | V- — Bottom-of-stack (cell 0 ground reference) |
| 腳位 61 | NC — Not connected (per datasheet) |
| 腳位 62 | NC — Not connected (per datasheet) |
| 腳位 63 | NC — Not connected (per datasheet) |
| 腳位 64 | EP — Exposed pad - thermal and ground connection (solder to PCB) |
典型應用
LTC6813HLWE 適用於 7 應用s: Electric Vehicle Traction Battery BMS, Stationary Energy Storage System (ESS), Industrial E-Forklift / AGV Battery Packs, Telecom 48 V Backup Battery Monitoring, Solar + Battery Residential Storage Systems, Aerospace / UAV High-Voltage Packs, Portable Medical Battery Packs.
Electric Vehicle Traction Battery BMS
The LTC6813HLWE is the standard cell monitor for 400 V and 800 V EV traction packs because it covers 18 series cells with < 2.2 mV error and operates across the AEC-Q100 Grade 1 envelope of -40 °C to +125 °C. Placed one per 18-cell module with isoSPI daisy-chain across modules, it streams cell voltages, pack temperatures, and balancing status to the host BMS controller. Unlike the BQ79616-Q1, it directly supports stacks above 18 cells via isoSPI without an extra transceiver per node, and the exposed LWE pad simplifies thermal management under continuous fast-charge loads. Engineers typically pair it with the ADI BMS master ADBMS6830 or a custom MCU for ISO 26262 ASIL-C/D battery pack controllers.
推薦
Stationary Energy Storage System (ESS)
In 1000 V-class stationary energy storage racks, the LTC6813HLWE provides redundant cell telemetry per 18-cell string with passive balancing and built-in self-test for safe operation across years of float duty. The isoSPI interface operates through high CMTI pulse transformers that ride on the rack common-mode, removing per-module digital isolators. With < 2.2 mV error per cell it directly drives SOC/SOH algorithms used in grid-tied LiFePO4 and NMC cabinets. Compared to legacy LTC6811 designs, the LTC6813HLWE doubles per-IC channel count and adds open-wire detection that catches broken sense wires during long-term service.
推薦
Industrial E-Forklift / AGV Battery Packs
Electric forklifts and automated guided vehicles use 48 V to 96 V Li-ion packs where the LTC6813HLWE's 18-cell capacity matches the typical 17- or 18-cell stack configuration. Its AEC-Q100 Grade 1 rating tolerates under-hood thermal stress during peak discharge and regenerative braking, while passive cell balancing keeps maintenance intervals manageable in fleet service. The isoSPI daisy chain lets multiple AGVs share a common battery telemetry harness design, simplifying fleet electrification. Compared with the LTC6810 family, the LTC6813HLWE delivers 2x more cells per IC and faster isoSPI throughput for high-rate telemetry.
推薦
Telecom 48 V Backup Battery Monitoring
Telecom backup cabinets often use 48 V nominal lead-acid or Li-ion strings of 13 to 18 cells, exactly the channel count supported by the LTC6813HLWE. The device delivers < 2.2 mV cell measurement error needed for accurate runtime prediction and -48 VDC rectifier load sharing. Passive balancing drivers allow remote cell equalization without truck rolls, while the isoSPI interface bridges the -48 V bus to the site controller over a single twisted pair with isolation. Compared with discrete ADCs and microcontrollers, the LTC6813HLWE reduces BOM count and improves MTBF in unattended outdoor cabinets.
推薦
Solar + Battery Residential Storage Systems
Residential solar-plus-storage stacks use 14 to 18 series LiFePO4 cells where the LTC6813HLWE provides the per-cell telemetry required for safe operation with high-voltage hybrid inverters. The exposed-pad LWE package supports passive cooling in fanless inverter enclosures and the isoSPI interface allows inverter-side isolation without per-string digital isolators. With < 2.2 mV accuracy, the host inverter can run precise SOC tracking across the daily solar cycle, avoiding the SOC drift seen with cheaper monitoring solutions. Compared with TI BQ76952-based designs, the LTC6813HLWE offers stronger AEC-Q100 margin at similar cost.
推薦
Aerospace / UAV High-Voltage Packs
UAVs and eVTOL aircraft rely on high-discharge Li-ion packs in the 18S to 22S range where the LTC6813HLWE's AEC-Q100 Grade 1 envelope, < 2.2 mV accuracy, and isoSPI common-mode tolerance are essential. Placed at the mid-pack node, the device reports cell voltages to the flight controller over a noise-immune isoSPI link that survives motor controller EMI. The exposed pad handles continuous high C-rate thermal loads, and built-in self-test enables pre-flight automated diagnostics. Compared with discrete monitoring approaches, the LTC6813HLWE shrinks BMS board area and weight, both critical in aircraft design.
推薦
Portable Medical Battery Packs
Portable medical devices (ventilators, infusion pumps, mobile ultrasound) increasingly use Li-ion packs with 10 to 18 cells where the LTC6813HLWE provides medical-grade telemetry with < 2.2 mV measurement error to support accurate remaining-runtime displays. Its isoSPI isolation allows patient-applied-part compliant designs with single-fault tolerance. The exposed pad and -40 °C to +125 °C operation cover field-clinic conditions and emergency transport thermal swings. Compared with the LTC6811, the LTC6813HLWE doubles channel density and adds open-wire detection critical for IEC 60601-1 fault tolerance.
推薦
推薦產品摘要
工程參考資料，適用於 LTC6813HLWE — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LTC6813ILWE-1#PBF | LTC6813HLWE-1#3ZZTRPBF | LTC6813HLWE-1#PBF |
|---|---|---|---|---|
| Package | 64-LQFP-EP (LWE) 10x10 mm | 64-LQFP-EP (LWE) 10x10 mm | 64-LQFP-EP (LWE) 10x10 mm | 64-LQFP-EP (LWE) 10x10 mm |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Measured Cells | Up to 18 | Up to 18 | Up to 18 | Up to 18 |
| Cell Measurement Error | < 2.2 mV | < 2.2 mV | < 2.2 mV | < 2.2 mV |
| Operating Temperature | -40 °C to +125 °C | -40 °C to +85 °C | -40 °C to +125 °C | -40 °C to +125 °C |
| AEC-Q100 Grade 1 | Yes (#3ZZ) | No (industrial) | Yes (#3ZZ) | No |
| Communication Interface | SPI / isoSPI 2 Mbps | SPI / isoSPI 2 Mbps | SPI / isoSPI 2 Mbps | SPI / isoSPI 2 Mbps |
| Passive Cell Balancing | Yes (per cell) | Yes (per cell) | Yes (per cell) | Yes (per cell) |
主要差異化特點
- AEC-Q100 Grade 1 with controlled manufacturing #3ZZ suffix (對比LTC6813ILWE-1#PBF)
- 18 cells per IC with < 2.2 mV total error (對比TI BQ79616-Q1)
- isoSPI 2 Mbps daisy chain with built-in transformer drive (對比NXP MC33771B)
- Pin-compatible tape-and-reel variant for high-volume lines (對比LTC6813HLWE-1#3ZZTRPBF)
設計說明
Solder the exposed pad (pin 64) to a continuous copper pour on at least 4 inner layers with stitched thermal vias; the LWE package relies on the pad for heat removal. Estimated: with 18 cells at 4.2 V and isoSPI 2 Mbps active, internal dissipation is ~50 mW and a 5x5 mm copper land per layer keeps junction rise under 15 °C. Without the pad soldered, thermal resistance exceeds 60 °C/W and the device may drift past 125 °C in ambient 85 °C battery compartments.
Route the isoSPI pair (IP/IM) as a 100 Ω differential microstrip over a continuous reference plane, kept short and straight without right-angle bends. Use a 1:1 pulse transformer (e.g. ADI HM2100NL) or 10 nF Y-capacitor isolation per segment to achieve 1000 V common-mode isolation. Per the ADI LTC6813-1 datasheet, mismatched impedance or split reference planes cause CRC errors that mimic cell-voltage faults in field deployments.
Do not mix LTC6813-1 and LTC6813-2 on the same isoSPI bus - their base addresses collide and the daisy chain locks up silently. Always order parts from one variant per stack design. Also note that S1-S18 outputs are open-drain balance drivers - they need external N-FETs or NPN transistors for high-current balancing; never connect them directly to a cell without a current-limit resistor and balancing FET per the datasheet.
Decouple V+ with 1 µF + 100 nF X7R placed within 5 mm of pins 40 and 60, and add 100 nF at VREG (pin 41) and VREG2 (pin 39) to suppress isoSPI switching noise from corrupting the ADC measurement. Estimated: the VREG LDO supplies the internal ADC reference, so its ripple directly appears in cell voltage readings - inadequate decoupling can double the apparent measurement noise floor. Per ADI demo circuit DC2259, also place a 100 nF at REF (pin 42).
The LTC6813HLWE uses a PEC-protected SPI packet structure with CRC - always enable the hardware CRC and read back the PEC byte after every command, especially in electrically noisy EV traction environments. Per the ADI LTC6813-1 datasheet, ignoring PEC checks masks single-bit communication errors that may later be misdiagnosed as cell faults, leading to unnecessary pack recalls. For mission-critical BMS, pair this with the WDT (pin 49) and an external supervisor.
合規資訊
AEC-Q100 Grade 1 qualified via the #3ZZ suffix per ADI LTC6813-1 datasheet. RoHS compliant. Halogen-free status not confirmed in verified web data - set unknown.
