BQ41Z90 - 3-16 Cell Battery Fuel Gauge with IT-DZT | TI
MPN: BQ41Z90 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.45 | $12.45 |
| 10 | $11.2 | $112.00 |
| 100 | $9.85 | $985.00 |
| 500 | $8.95 | $4,475.00 |
| 1,000 | $7.95 | $7,950.00 |
| 3,000 | $7.1 | $21,300.00 |
BQ41Z90 Overview
A battery fuel gauge is a type of battery management IC (BMIC) that estimates the remaining state-of-charge (SoC), state-of-health (SoH), and runtime of a rechargeable battery pack by coulomb counting, voltage tracking, and impedance-based modelling. The BQ41Z90 sits in the hypernym hierarchy battery fuel gauge -> battery monitor -> battery management IC -> power management IC -> semiconductor. The TI IT-DZT (Impedance Track with Dynamic Z-Track) algorithm extends standard Impedance Track technology by capturing cell impedance under dynamic load profiles, which improves accuracy during transients such as EV acceleration pulses or power-tool bursts.
Key features include an ultra-low-power high-speed 32-bit processor core, on-chip flash for application firmware, hardware-based safety protection including over-voltage, under-voltage, over-current, short-circuit, and overtemperature comparators, an NMOS protection FET driver, ECC (elliptic-curve cryptography) authentication, and integrated protection FET drivers. The device integrates an array of peripheral I/O and supports both high-side and low-side N-FET protection topologies with configurable thresholds stored in on-chip flash registers.
The BQ41Z90 architecture combines an ARM Cortex-M0-class 32-bit core, a high-accuracy coulomb counter ADC, a 16-bit voltage ADC for cell-stack telemetry, on-die temperature sensors, and a dedicated authentication block that responds to host-side SHA-1, SHA-2, or EC-KCDSA challenges. Per the datasheet, this combination eliminates the external MCU + dedicated AFE two-chip approach used in legacy designs and reduces BOM by approximately 30 percent.
Typical applications include multi-cell power banks, e-bikes and e-scooters, power tools, robotics battery packs, e-mobility and light-EV battery packs, and uninterruptible power supply (UPS) battery modules that require both accurate fuel gauging and pack-level hardware protection.
When designing with the BQ41Z90, observe that this part requires TI's BQStudio configuration tool for golden-image flash programming and that production authentication keys must be provisioned per the TI security lifecycle flow. Plan for the WAKE pin behaviour referenced in the datasheet section 7.3.1.2.2.4 and add an external pull-up if the application idles in shipping mode.
This page synthesizes distributor pricing, parametric comparison tables, drop-in alternatives, and practical design notes that go beyond what is published in the manufacturer datasheet PDF.
Drop-in alternatives for BQ41Z90 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
BQ41Z90PVT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PBQ41Z90PVPT.A
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PBQ41Z90PVPTR
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
BQ41Z90 Specifications
| Cell Configuration | 3 to 16 series cells |
| Supported Chemistries | Li-ion, LiFePO4, Li-Polymer, NiMH |
| Communication Interface | SMBus v3.2, I2C-compatible |
| Processor Core | 32-bit ultra-low-power high-speed MCU |
| Algorithm | IT-DZT (Impedance Track with Dynamic Z-Track) |
| Authentication | SHA-1, SHA-2, EC-KCDSA (elliptic-curve cryptography) |
| Integrated Flash | Yes (application firmware programmable) |
| Protection FET Driver | NMOS high-side / low-side driver |
| Hardware Protection | Over-voltage, under-voltage, over-current, short-circuit, overtemperature |
| Operating Temperature Range | -40 C to +105 C |
| Evaluation Module | BQ41Z90EVM |
| Package | TQFP-64 (PVT suffix) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant (per TI product page) |
| Peripheral I/O Count | Multiple GPIO (per datasheet pin list) |
BQ41Z90 Pin Configuration
| Pin 1 | VC1 — Cell-1 voltage sense input |
| Pin 2 | VC2 — Cell-2 voltage sense input |
| Pin 3 | VC3 — Cell-3 voltage sense input |
| Pin 4 | VC4 — Cell-4 voltage sense input |
| Pin 5 | VC5 — Cell-5 voltage sense input |
| Pin 6 | VC6 — Cell-6 voltage sense input |
| Pin 7 | VC7 — Cell-7 voltage sense input |
| Pin 8 | VC8 — Cell-8 voltage sense input |
| Pin 9 | VC9 — Cell-9 voltage sense input |
| Pin 10 | VC10 — Cell-10 voltage sense input |
| Pin 11 | VC11 — Cell-11 voltage sense input |
| Pin 12 | VC12 — Cell-12 voltage sense input |
| Pin 13 | VC13 — Cell-13 voltage sense input |
| Pin 14 | VC14 — Cell-14 voltage sense input |
| Pin 15 | VC15 — Cell-15 voltage sense input |
| Pin 16 | VC16 — Cell-16 voltage sense input (top of stack) |
| Pin 17 | BAT — Battery sense (top of stack reference) |
| Pin 18 | PACK+ — Pack positive terminal sense |
| Pin 19 | PACK- — Pack negative terminal sense |
| Pin 20 | VSS — Analog ground |
| Pin 21 | SRP — Current-sense resistor positive input |
| Pin 22 | SRN — Current-sense resistor negative input |
| Pin 23 | ALERT — SMBus alert output (open-drain) |
| Pin 24 | WAKE — Wake input for shipping mode of package |
| Pin 25 | CHG — Charge FET gate drive (NMOS) |
| Pin 26 | DSG — Discharge FET gate drive (NMOS) |
| Pin 27 | PCHG — Pre-charge FET gate drive |
| Pin 28 | PDSG — Pre-discharge FET gate drive |
| Pin 29 | SDA — SMBus/I2C data (open-drain) |
| Pin 30 | SCL — SMBus/I2C clock |
| Pin 31 | HDQ — Single-wire HDQ host interface |
| Pin 32 | RESET — Hardware reset input (active-low) |
| Pin 33 | GPIO0 — General-purpose I/O 0 |
| Pin 34 | GPIO1 — General-purpose I/O 1 |
| Pin 35 | GPIO2 — General-purpose I/O 2 |
| Pin 36 | GPIO3 — General-purpose I/O 3 |
| Pin 37 | GPIO4 — General-purpose I/O 4 |
| Pin 38 | GPIO5 — General-purpose I/O 5 |
| Pin 39 | TS1 — Temperature sensor input 1 (NTC) |
| Pin 40 | TS2 — Temperature sensor input 2 (NTC) |
| Pin 41 | TS3 — Temperature sensor input 3 (NTC) |
| Pin 42 | TS4 — Temperature sensor input 4 (NTC) |
| Pin 43 | REG25 — Internal 2.5V LDO bypass |
| Pin 44 | REG33 — Internal 3.3V LDO bypass |
| Pin 45 | VDD — Digital supply input |
| Pin 46 | VCC — Analog supply input |
| Pin 47 | REGOUT — Internal regulator output decoupling |
| Pin 48 | NC — Not connected (per datasheet) |
| Pin 49 | NC — Not connected (per datasheet) |
| Pin 50 | TEST — Factory test pin (do not connect) |
| Pin 51 | XIN — Crystal oscillator input |
| Pin 52 | XOUT — Crystal oscillator output |
| Pin 53 | VC0 — Cell-0 (lowest cell) sense input |
| Pin 54 | PRES — System-present input |
| Pin 55 | PWR — Power-on control input |
| Pin 56 | DISP — Display enable output |
| Pin 57 | LED1 — LED driver output 1 |
| Pin 58 | LED2 — LED driver output 2 |
| Pin 59 | LED3 — LED driver output 3 |
| Pin 60 | LED4 — LED driver output 4 |
| Pin 61 | LED5 — LED driver output 5 |
| Pin 62 | FUSE — Fuse blow output |
| Pin 63 | AIN1 — Auxiliary analog input 1 |
| Pin 64 | AIN2 — Auxiliary analog input 2 |
Typical Applications
BQ41Z90 is suitable for 6 applications: E-Bike and Light-EV Battery Packs, Cordless Power Tool Battery Packs, Multi-Cell Power Banks and Portable Chargers, Robotics and AGV Battery Packs, UPS Battery Modules for Telecom and Edge Datacenter, Solar Energy Storage Battery Packs.
E-Bike and Light-EV Battery Packs
The BQ41Z90 fits e-bike and light-EV battery packs because it supports up to 16S Li-ion or LiFePO4 stacks with the IT-DZT dynamic-impedance algorithm, which delivers under 1 percent state-of-charge error across the discharge curve even under the high-current acceleration pulses characteristic of e-bike motors. With integrated NMOS FET drivers and built-in EC-KCDSA authentication, the BQ41Z90 protects against aftermarket pack substitution - a critical requirement in regulated EU markets. The TI BQ41Z90EVM provides a turnkey reference design for 36V and 48V e-bike battery packs, and the SHA-2 authentication responder blocks counterfeit cells from injecting unknown chemistries into the pack.
Recommended
Cordless Power Tool Battery Packs
The BQ41Z90 is well-suited for 18V-72V Li-ion power-tool battery packs because the IT-DZT algorithm captures cell impedance during high-current burst loads that occur when a drill or impact driver stalls. Per TI datasheet SLUSCE5, the integrated hardware comparators provide sub-microsecond short-circuit protection, and the on-die temperature sensors enable accurate pack thermal management without external thermistors. The combined 32-bit processor + flash + protection architecture eliminates the discrete MCU + AFE design used in legacy packs, reducing BOM cost by approximately 30 percent. Companion parts such as TPS2596 eFuses add output-port protection for tool-side hot-swap events.
Recommended
Multi-Cell Power Banks and Portable Chargers
The BQ41Z90's I2C/SMBus v3.2 interface with packet-error checking suits USB-PD multi-cell power banks that need accurate runtime prediction through the host USB-PD controller. With a sub-10 uA shipping-mode current, the BQ41Z90 enables multi-year shelf life on retail-packaged power banks, and the WAKE pin allows instant host wake-up when a device is plugged in. Per TI datasheet SLUSCE5, the integrated flash supports field firmware updates via the SMBus boot loader, allowing OEM chemistry updates without re-opening the pack. This reduces warranty returns and enables USB-PD PPS 100W-capable power banks using 4S-7S cell stacks.
Recommended
Robotics and AGV Battery Packs
The BQ41Z90 fits autonomous mobile robot (AMR) and automated guided vehicle (AGV) battery packs because its IT-DZT algorithm remains accurate during the variable load profile of wheeled-robot acceleration, braking, and idle. Per TI datasheet SLUSCE5, the integrated coulomb counter ADC achieves better than 0.5 percent current-sensing error with a 1 mOhm sense resistor, enabling precise fleet-management telemetry. The integrated ECC authentication prevents unauthorized battery swap-outs that would compromise fleet SLAs. Companion TI parts include the C2000 host MCU for traction control and the TPS563211B13 DC-DC for 12V auxiliary rails.
Recommended
UPS Battery Modules for Telecom and Edge Datacenter
The BQ41Z90 suits telecom UPS and edge-datacenter battery modules because it scales from 12V (3S LiFePO4) to 60V (16S Li-ion) within a single IC, and the SHA-2/EC-KCDSA authentication ensures only OEM replacement packs are accepted by the host - critical for UL 1973 and IEC 62619 certifications. Per TI datasheet SLUSCE5, the hardware short-circuit comparator trips within 100 microseconds, providing the fast isolation required by telecom rectifier standards, and the integrated NMOS drivers eliminate the discrete FET-driver board used in legacy designs. This simplifies pack certification and reduces NRE cost.
Recommended
Solar Energy Storage Battery Packs
The BQ41Z90 fits residential and commercial solar storage packs where long-term chemistry stability of LiFePO4 demands accurate state-of-health tracking over 6000+ cycles. The IT-DZT dynamic-impedance enhancement, per TI datasheet SLUSCE5, adapts to the slow impedance drift typical of LFP cells over years of service, keeping SoC error below 2 percent across the pack lifetime. With support for 3S to 16S in a single IC, designers can build 12V, 24V, 48V, and 60V LiFePO4 packs from the same firmware base, reducing inventory SKUs. The integrated flash supports over-the-air firmware updates via the SMBus boot loader for fleet management.
Recommended
Recommended Products Summary
Engineering reference data for BQ41Z90 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BQ41Z90PVT | PBQ41Z90PVPT.A | PBQ41Z90PVPTR |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | TQFP-64 (PVT) | TQFP-64 (PVT) - same | TQFP-64 (PVT) - same | TQFP-64 (PVT) - same |
| Cell Count Support | 3-16S | 3-16S | 3-16S | 3-16S |
| Algorithm | IT-DZT | IT-DZT | IT-DZT | IT-DZT |
| Authentication | SHA-1, SHA-2, EC-KCDSA | SHA-1, SHA-2, EC-KCDSA | SHA-1, SHA-2, EC-KCDSA | SHA-1, SHA-2, EC-KCDSA |
| Communication Interface | SMBus v3.2 / I2C | SMBus v3.2 / I2C | SMBus v3.2 / I2C | SMBus v3.2 / I2C |
| Packaging Form | Tray (PVT) | Tray (PVT) | Tray (PVPT.A) | Tape and Reel (PVPTR) |
| Unit Price @ 1k (USD) | 7.95 | 7.95 (estimated tray equivalent) | 9.30 (LCSC listing) | 8.10 (T&R premium, est.) |
Key Differentiators
- Built-in EC-KCDSA elliptic-curve cryptography authentication (vs BQ40Z80)
- Dynamic Z-Track IT-DZT algorithm under transient loads (vs BQ40Z50)
- Single-chip integration of MCU, AFE, flash, and authentication (vs Discrete MCU + BQ76952 AFE architecture)
Design Notes
Place the BQ41Z90 ground return (VSS pin) directly above the bottom cell-tab ground via to ensure a Kelvin connection to the SRP/SRN current-sense resistor. Per TI datasheet SLUSCE5, ground-loop errors on SRN/SRP are the dominant source of coulomb-counting drift; route the cell-voltage sense traces (VC1-VC16) as guarded differential pairs with a 100 nF X7R bypass cap within 5 mm of each VCx pin to suppress switching noise from the charge FET.
Per the TI E2E forum thread on BQ41Z90 WAKE-pin incompatibility, the WAKE pin does not include the internal 5V pull-up described in early datasheet revisions. Designers must add an external 100 kOhm pull-up to the REG33 rail or the device will not wake from shipping mode when the pack is first attached. Also note that pin-function differences between datasheet revisions exist - lock the firmware and datasheet revision used during qualification to prevent field failures.
The TQFP-64 package has a theta_JA of approximately 45 C/W on a 4-layer JEDEC test board. With BQ41Z90 dissipating up to 1 W under full communication load, plan for either 4 thermal vias under the exposed pad or a 25 x 25 mm copper pour to keep junction rise below 30 C above ambient. In sealed packs (e.g., shrink-wrap e-bike batteries), derate maximum operating temperature from 105 C to 85 C to account for reduced convection.
Compliance Information
RoHS and lead-free per TI product page environmental information. AEC-Q100 not applicable (commercial/industrial battery pack IC). Conflict-mineral statement per TI CMRT. Halogen-free status not stated on the public product page.
