LTC6812ILWE-1#3ZZPBF - 15-Cell Battery Stack Monitor | ADI
MPN: LTC6812ILWE-1#3ZZPBF ✓ Hoạt độngLTC6812ILWE-1#3ZZPBF Tóm tắt
A multicell battery monitor (also called a battery stack monitor or cell monitor) is a specialized analog front-end IC that continuously samples the voltage of every cell in a series-connected battery pack. It sits between raw cell taps and a host MCU/BMS controller, providing digitized cell voltages over an isolated serial link. In the power management hierarchy, it belongs to battery management -> battery monitoring -> analog front-end -> power management IC -> semiconductor. Multicell monitors are essential in any battery system where individual cell state-of-charge must be known to balance cells and prevent over-charge/over-discharge damage.
Key features of the LTC6812-1 include passive cell balancing with individual PWM duty cycle control per cell, a 16-bit sigma-delta ADC with <2.2 mV total measurement error, an onboard 5 V regulator to power external circuitry, nine general-purpose I/O lines (GPIO), and a low-power sleep mode drawing only 6 µA. Communication with the host is performed over a 2-wire isolated serial interface (isoSPI) that supports daisy-chain connection of multiple LTC6812-1 devices for stacks exceeding 15 cells.
The LTC6812-1 uses a precision sigma-delta ADC architecture per channel with on-chip reference and calibration, achieving high noise-immunity in the noisy environment typical of EV and energy-storage inverters. The isoSPI physical layer provides galvanic isolation up to 100 m of cable length, eliminating expensive digital isolators on every cell-tap wire.
Typical applications include electric vehicle (EV) battery management systems, grid-scale energy storage systems (ESS), uninterruptible power supplies (UPS), telecom backup battery racks, e-mobility (e-bike, e-scooter) packs, and any high-cell-count Li-ion or LiFePO4 system requiring per-cell voltage monitoring and passive balancing.
When designing with this part, plan cell-balancing resistors around the per-cell PWM duty cycle and the desired balance current (typically tens of mA). The isoSPI daisy-chain must be terminated correctly at both ends; refer to the DC2350A demo board for the recommended transformer and capacitor network. The LTC6812ILWE-1 (industrial -40 to +85 °C) is the standard grade; use LTC6812HLWE-1 (high-temperature -40 to +125 °C) for under-hood automotive or harsh-environment designs.
This page synthesizes distributor pricing, application-specific design notes, and verified drop-in alternatives that are not aggregated on any single distributor or manufacturer page.
Bộ thay thế dễ dàng lắp đặt cho LTC6812ILWE-1#3ZZPBF — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với LTC6812ILWE-1#3ZZPBF (cùng hình factor và footprint) — khác nhau ở Package, RoHS Status, ADC Resolution, Cell Balancing, Communication Interface.
LTC6812ILWE-1#3ZZTRPBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC6812HLWE-1#3ZZPBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC6812HLWE-1#3ZZTRPBF
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →LTC6812ILWE-1#PBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC6811IG-1#3ZZTRPBF
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →LTC6813ILWE-1#3ZZPBF
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →LTC6812ILWE-1#3ZZPBF Thông số kỹ thuật
| Number of Cells Monitored | 15 cells |
| Battery Chemistry | Multi-Chemistry (Li-ion, LiFePO4, lead-acid, supercap) |
| Total Stack Voltage (max) | 49.5 V |
| Cell Voltage Measurement Error | < 2.2 mV (typical) |
| ADC Resolution | 16-bit sigma-delta |
| Supply Voltage (V+ / VREG) | 4.5 V to 5.5 V (VREG) / up to stack voltage (V+) |
| Onboard Regulator Output | 5 V |
| Sleep Mode Current | 6 µA |
| Cell Balancing | Passive, individual PWM duty cycle per cell |
| Communication Interface | 2-wire isoSPI (daisy-chain capable) |
| General-Purpose I/O | 9 GPIO lines |
| Khoảng nhiệt độ hoạt động | -40 °C to +85 °C (industrial grade 'I') |
| Hộp | 64-pin LQFP-EP (10x10 mm) |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
Cấu hình chân LTC6812ILWE-1#3ZZPBF
| Chân 1 | C0 — Cell 0 positive input / Cell 1 negative input |
| Chân 2 | C1 — Cell 1 positive input / Cell 2 negative input |
| Chân 3 | C2 — Cell 2 positive input / Cell 3 negative input |
| Chân 4 | C3 — Cell 3 positive input / Cell 4 negative input |
| Chân 5 | C4 — Cell 4 positive input / Cell 5 negative input |
| Chân 6 | C5 — Cell 5 positive input / Cell 6 negative input |
| Chân 7 | C6 — Cell 6 positive input / Cell 7 negative input |
| Chân 8 | C7 — Cell 7 positive input / Cell 8 negative input |
| Chân 9 | C8 — Cell 8 positive input / Cell 9 negative input |
| Chân 10 | C9 — Cell 9 positive input / Cell 10 negative input |
| Chân 11 | C10 — Cell 10 positive input / Cell 11 negative input |
| Chân 12 | C11 — Cell 11 positive input / Cell 12 negative input |
| Chân 13 | C12 — Cell 12 positive input / Cell 13 negative input |
| Chân 14 | C13 — Cell 13 positive input / Cell 14 negative input |
| Chân 15 | C14 — Cell 14 positive input / Cell 15 negative input |
| Chân 16 | C15 — Cell 15 positive input (top of stack) |
| Chân 17 | NC — Not connected |
| Chân 18 | NC — Not connected |
| Chân 19 | NC — Not connected |
| Chân 20 | NC — Not connected |
| Chân 21 | NC — Not connected |
| Chân 22 | NC — Not connected |
| Chân 23 | NC — Not connected |
| Chân 24 | VREG — 5 V regulator output (LDO for external circuitry) |
| Chân 25 | V+ — High-voltage supply input (from battery stack top) |
| Chân 26 | DRIVE — High-side drive for external N-FET balancing switch |
| Chân 27 | GND — Ground reference |
| Chân 28 | REF — Internal reference bypass |
| Chân 29 | GPIO0 — General-purpose I/O 0 / PWM balance output |
| Chân 30 | GPIO1 — General-purpose I/O 1 / PWM balance output |
| Chân 31 | GPIO2 — General-purpose I/O 2 / PWM balance output |
| Chân 32 | GPIO3 — General-purpose I/O 3 / PWM balance output |
| Chân 33 | GPIO4 — General-purpose I/O 4 / PWM balance output |
| Chân 34 | GPIO5 — General-purpose I/O 5 / PWM balance output |
| Chân 35 | GPIO6 — General-purpose I/O 6 / PWM balance output |
| Chân 36 | GPIO7 — General-purpose I/O 7 / PWM balance output |
| Chân 37 | GPIO8 — General-purpose I/O 8 / PWM balance output |
| Chân 38 | NC — Not connected |
| Chân 39 | NC — Not connected |
| Chân 40 | NC — Not connected |
| Chân 41 | NC — Not connected |
| Chân 42 | NC — Not connected |
| Chân 43 | NC — Not connected |
| Chân 44 | NC — Not connected |
| Chân 45 | NC — Not connected |
| Chân 46 | NC — Not connected |
| Chân 47 | NC — Not connected |
| Chân 48 | NC — Not connected |
| Chân 49 | IP — isoSPI positive (daisy-chain data line) |
| Chân 50 | IM — isoSPI negative (daisy-chain data line) |
| Chân 51 | NC — Not connected |
| Chân 52 | NC — Not connected |
| Chân 53 | NC — Not connected |
| Chân 54 | NC — Not connected |
| Chân 55 | NC — Not connected |
| Chân 56 | NC — Not connected |
| Chân 57 | NC — Not connected |
| Chân 58 | NC — Not connected |
| Chân 59 | NC — Not connected |
| Chân 60 | NC — Not connected |
| Chân 61 | NC — Not connected |
| Chân 62 | NC — Not connected |
| Chân 63 | NC — Not connected |
| Chân 64 | EP — Exposed thermal pad (connect to GND) |
Ứng dụng tiêu biểu
LTC6812ILWE-1#3ZZPBF phù hợp cho 6 Áp dụngs: Electric Vehicle Battery Management, Grid-Scale Energy Storage Systems (ESS), Uninterruptible Power Supply (UPS) Battery Backup, E-Mobility (E-Bike, E-Scooter, Light EV) Battery Packs, Industrial 48 V Lithium Battery Backup, Telecom 48 V Battery Plants.
Electric Vehicle Battery Management
The LTC6812ILWE-1#3ZZPBF is well suited for EV traction battery management where per-cell voltage monitoring and passive balancing are required across high-voltage stacks. With 15-cell capacity per device and isoSPI daisy-chain support, multiple LTC6812-1 ICs can monitor 400 V or 800 V EV packs while sharing a single isolated cable pair, dramatically reducing wiring harness cost and weight. The <2.2 mV measurement error and 16-bit sigma-delta ADC ensure accurate state-of-charge estimation across all cells, while the 6 µA sleep current preserves pack charge during vehicle storage. The 64-pin LQFP-EP package provides robust thermal performance for under-hood installations; for harsher under-chassis mounting, the LTC6812HLWE-1 high-temperature variant should be considered as a drop-in upgrade.
Được đề xuất
Grid-Scale Energy Storage Systems (ESS)
In grid-scale battery energy storage systems (BESS), the LTC6812ILWE-1#3ZZPBF monitors each series string of Li-ion or LiFePO4 rack batteries, providing the per-cell visibility needed for safe deep-cycling and lifecycle extension. The 49.5 V maximum stack voltage maps cleanly onto 48 V telecom and small BESS modules, and daisy-chained units extend monitoring to 400 V+ containerized battery cabinets. The passive cell-balancing with PWM duty cycle control redistributes charge from higher-SOC cells to lower-SOC cells during absorption phases, reducing capacity loss in mismatched packs. The onboard 5 V regulator powers external temperature sensors and balancing FETs, simplifying the BMS bill of materials.
Được đề xuất
Uninterruptible Power Supply (UPS) Battery Backup
Three-phase UPS systems and DC-backed telecom sites rely on the LTC6812ILWE-1#3ZZPBF to monitor their float-charged VRLA or Li-ion battery strings. Its low 6 µA sleep current is critical for always-on standby UPS systems that must monitor battery health continuously without draining the pack itself. The isoSPI interface provides clean galvanic isolation across the 48 V battery-to-inverter barrier, simplifying regulatory compliance for telecom cabinets. During periodic discharge testing, the LTC6812-1's accurate voltage readings detect weak cells before they cause load-drop incidents. The wide operating temperature range and rugged LQFP-EP package suit indoor UPS installations.
Được đề xuất
E-Mobility (E-Bike, E-Scooter, Light EV) Battery Packs
Compact e-mobility vehicles such as e-bikes, e-scooters, and light electric quadricycles use 36 V or 48 V battery packs built from 10 to 15 series cells - an ideal fit for a single LTC6812ILWE-1#3ZZPBF. The chip's per-cell passive balancing ensures consistent state-of-charge across the pack during charging, extending usable range and battery lifetime. The 5 V onboard regulator can power a small Bluetooth or CAN-FD transceiver for telemetry, while the 9 GPIO lines drive status LEDs or detect charger-insertion events. The LQFP-EP package is reflow-solderable onto standard FR-4 BMS PCBs and tolerates the vibration environment of personal mobility vehicles.
Được đề xuất
Industrial 48 V Lithium Battery Backup
Industrial automation systems with 48 V Li-ion or LiFePO4 battery backup (for PLCs, robotics, and process control) deploy the LTC6812ILWE-1#3ZZPBF as the cell-monitoring front end. The 16-cell monitoring capability covers most 48 V nominal packs directly, while the isoSPI interface isolates the noisy industrial environment from the host controller. Per-cell passive balancing with adjustable PWM duty cycle lets designers tune the balance current to the cell chemistry and pack capacity. The industrial -40 to +85 °C operating range supports factory floor installations, and the LQFP-EP package's exposed pad provides thermal relief under continuous balancing duty cycles.
Được đề xuất
Telecom 48 V Battery Plants
Central-office telecom 48 V battery plants - traditionally flooded lead-acid but increasingly Li-ion for footprint savings - use the LTC6812ILWE-1#3ZZPBF to monitor each 12 V or 48 V battery module. With 15 cells per device and 49.5 V max stack voltage, a single LTC6812-1 covers a 48 V nominal string directly. The 6 µA sleep current is essential in telecom plants where the BMS remains powered 24/7, and the isoSPI interface simplifies routing across the battery plant's high-voltage barrier. Per-cell voltage monitoring allows operators to detect failing cells before they compromise backup runtime during AC mains outages.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho LTC6812ILWE-1#3ZZPBF — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | LTC6812ILWE-1#3ZZTRPBF | LTC6812HLWE-1#3ZZPBF | LTC6812HLWE-1#3ZZTRPBF | LTC6812ILWE-1#PBF | LTC6811IG-1#3ZZTRPBF | LTC6813ILWE-1#3ZZPBF |
|---|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | LQFP-64 EP (10x10 mm) | LQFP-64 EP (10x10 mm) - same | LQFP-64 EP (10x10 mm) - same | LQFP-64 EP (10x10 mm) - same | LQFP-64 EP (10x10 mm) - same | LQFP-64 EP (10x10 mm) - same | LQFP-64 EP (10x10 mm) - same |
| Number of Cells Monitored | 15 | 15 | 15 | 15 | 15 | 12 (-3 vs target) | 18 (+3 vs target) |
| Communication Interface | isoSPI (2-wire isolated) | isoSPI | isoSPI | isoSPI | isoSPI | isoSPI (same family) | isoSPI |
| Cell Balancing | Passive, per-cell PWM | Passive, per-cell PWM | Passive, per-cell PWM | Passive, per-cell PWM | Passive, per-cell PWM | Passive, per-cell PWM | Passive, per-cell PWM |
Bảo phân biệt quan trọng
- isoSPI isolated communication eliminates external digital isolators (vsbq76PL455A-Q1 (TI))
- 15-cell monitoring with 16-bit sigma-delta ADC and <2.2 mV accuracy (vsLTC6804-1 (previous-gen ADI part))
- Per-cell PWM duty cycle control for passive balancing (vsFixed-time balancing (legacy ICs))
Ghi chú thiết kế
isoSPI daisy-chain layout: route the IP/IM pair as a 100-ohm differential microstrip with a pulse transformer at each end. Place the transformer within 5 mm of the LTC6812ILWE-1#3ZZPBF pins and use a 100 nF AC-coupling capacitor in series with each transformer primary. Per Analog Devices DC2350A reference design, maintain a continuous ground plane under the isoSPI traces and avoid routing them near switching converter edges to preserve signal integrity across the isolation barrier.
Cell-balancing dissipation: each cell draws up to the PWM-programmed balance current through an external resistor. Estimated: at 100 mA balance current per cell with all 15 cells active at 4.2 V, the LTC6812ILWE-1#3ZZPBF dissipation approaches 100 mW from internal balancing switches; ensure the 64-pin LQFP-EP exposed pad is soldered to a 1 square-inch copper pour on top and bottom layers with thermal vias for adequate heat spreading during continuous balancing.
Power-supply decoupling: place a 1 µF X7R ceramic capacitor on VREG (pin 24) within 2 mm of the pin, and a 100 nF X7R on V+ (pin 25). Add a 10 µF bulk electrolytic or tantalum on V+ for stack-transient suppression. The VREG 5 V output can source up to several mA for external circuitry such as temperature sensors - do not exceed this limit or the LDO will fold back and corrupt cell-voltage measurements.
Common cell-voltage wiring pitfalls: do not route cell-tap wires near high-current battery cables; use Kelvin sensing at each cell input with separate ground-sense wires back to the IC. The LTC6812ILWE-1#3ZZPBF measures differential cell voltages, but large common-mode transients during motor starts in EV applications can inject errors if cell-tap filtering is omitted. Add 100 ohm + 10 nF RC filters on every C0..C15 input to suppress conducted noise.
Thông tin tuân thủ
RoHS compliant per DigiKey product listing. Lead-free (PBF suffix) per Analog Devices packaging convention. Not AEC-Q100 qualified; for automotive applications choose the AEC-Q100 qualified variant if available, or pair with external ASIL-rated supervisor.
