Part Datasheet Review
Assign Terminal Order and Pin Orientation, then run a schematic/symbol review.
Thought for 10 sec
I’ll assign terminal order and orientation by broad groups using your conventions, then run symbol/part checks and verify the schematic metadata.
Worked for 3 mins 13 sec
Assigned Terminal Order and Pin Orientation for all 65 terminals: Power = order 1/top, Cell Monitor = 2/left, Communication = 3/right, GPIO = 4/right, Current Sense = 5/left, Thermal Pad = 9/bottom, Ground = 10/bottom.
Open items:
- Schematic/symbol review returned no open warnings/errors for the checked component-review categories.
- Footprint quality is still a separate unresolved issue from the prior review.
Suggested next steps:
- Rebuild the HTQFP-64 PAP0064F footprint.
- Run footprint/layout checks after footprint generation.
- Publish the part once footprint checks pass.
Build footprint and checks
Rebuild footprint
Run footprint checks
Prepare for publishing
Refine this doc
Ask about this doc
BQ79656PAPRQ1 Part Review
Date: 2026-07-20
Sources Reviewed
- Current Flux part project:
silicon-yard/bq79656paprq1 - Current set Datasheet URL property:
https://storage.googleapis.com/graviton-electric-symbols/document_assets/user-uploaded/2dc60be860c57e0bde11fa735e474fe5eee3cb99dfa2ad69f8b1a4837736382e.pdf - Official TI orderable-part page found by web search:
https://www.ti.com/product/BQ79656-Q1/part-details/BQ79656PAPRQ1 - Official TI datasheet URL found by web search:
https://www.ti.com/lit/gpn/BQ79656-Q1/https://www.ti.com/lit/ds/symlink/bq79656-q1.pdf
Note: The part already had a Datasheet URL set, so I did not overwrite it under the user's conditional instruction. The existing URL is an uploaded PDF copy rather than the direct TI official URL.
Current Part Metadata
Table
| Field | Current value | Datasheet / TI value | Result |
|---|---|---|---|
| Manufacturer Part Number | BQ79656PAPRQ1 | BQ79656PAPRQ1 | Match |
| Manufacturer Name | Texas Instruments | Texas Instruments | Match |
| Description | Battery Management Automotive 16-S precision battery monitors, balancer, current sensor with ASIL-D compliance | Automotive 16-S precision battery monitor, balancer, current sensor with ASIL-D compliance | Match |
| Part Type | Sensors | Functionally battery-monitor / battery-management IC | Acceptable but broad; Integrated Circuit or Battery Management would be clearer if available |
| Designator Prefix | IC | IC/U-style IC prefix appropriate | Acceptable |
| Datasheet URL | Uploaded PDF copy | Official TI URL: https://www.ti.com/lit/gpn/BQ79656-Q1 | Valid datasheet present, but not the direct official TI URL |
| Package property | Not observed in project properties | HTQFP (PAP), 64 pins, PAP0064F PowerPAD TQFP | Missing package metadata |
| Pin/terminal count | 65 terminals | 64 package leads plus exposed PowerPAD/thermal pad shown as land pad 65 | Needs clarification: 65 is only valid as PowerPAD, not a normal signal pin |
Official Datasheet Key Specifications
- Device family: BQ79656-Q1 / BQ79654-Q1 / BQ79652-Q1 functional-safety-compliant automotive battery monitor family.
- Orderable part reviewed: BQ79656PAPRQ1.
- Package: HTQFP (PAP), 64 pins, 10 mm x 10 mm, 0.5 mm pitch, 1.2 mm max height, PAP0064F PowerPAD TQFP.
- Cell support: BQ79656-Q1 supports 6S to 16S battery modules.
- Cell measurement: main ADC effective 16-bit; AUX ADC effective 14-bit; feature summary lists +/-1.5 mV ADC accuracy, with detailed accuracy limits varying by temperature and cell voltage range.
- Current sensing: integrated 24-bit sigma-delta current-sense ADC; recommended SRP-SRN range -100 mV to +100 mV.
- Balancing: internal cell balancing, up to 240 mA balancing capability; balance resistor also sets internal balance current.
- Supplies/regulators: BAT/module recommended full-function range 9 V to 80 V; CVDD ~5 V, AVDD ~5 V, DVDD ~1.8 V, TSREF ~5 V, NEG5V charge pump around -5 V.
- Interfaces: isolated differential daisy-chain COMHP/COMHN and COMLP/COMLN; UART RX/TX; SPI master option on GPIOs.
- GPIO: GPIO1-GPIO8 support NTC thermistor input, ADC input, generic digital I/O, and SPI master roles depending configuration.
- Automotive/safety: AEC-Q100 qualified, grade 1 -40 C to +125 C ambient; documentation supports ISO 26262 system design; systematic and hardware capability up to ASIL D.
Pinout Cross-Check
The current schematic has terminal names and pin numbers that match the official BQ79656 64-lead pin table for pins 1 through 64.
Table
| Pin range | Datasheet function group | Current status |
|---|---|---|
| 1 | BAT, top-of-module supply/measurement input | Match |
| 2-34 alternating CB16..CB0 | Cell balancing pins | Match by pin number/name |
| 3-35 alternating VC16..VC0 | Cell voltage sense pins | Match by pin number/name |
| 36-39 | REFHM, REFHP, AVDD, AVSS | Match by pin number/name |
| 40-43 | COMLP, COMLN, COMHN, COMHP differential daisy-chain | Match by pin number/name |
| 44-50 | NEG5V, CVDD, CVSS, LDOIN, NPNB, DVDD, DVSS | Match by pin number/name |
| 51-62 | TSREF, RX, TX, GPIO8..GPIO1, NFAULT | Match by pin number/name |
| 63-64 | SRN, SRP current sense | Match by pin number/name |
| 65 | Datasheet land-pattern exposed PowerPAD / thermal pad, not in pin function table | Current terminal is AVSS_2; this is potentially misleading and not explicitly backed by the datasheet |
Symbol / Terminal Metadata Findings
Critical or high-priority issues:
- Pin descriptions are missing. No terminal currently has a
Pin Descriptionproperty populated, even though the datasheet provides detailed descriptions for every pin. - Pin types are all
Unspecified. The datasheet provides explicit types: P, GND, I, O, and I/O. Current terminals should be updated to Power, Ground, Input, Output, or Bi-Directional / Signal as appropriate. - Pin groups / sections are not populated. The symbol would be clearer with broad groups such as Power, Ground, Cell Voltage Sense, Cell Balancing, Daisy-Chain Communication, UART, GPIO, Current Sense, and Thermal Pad. For this user's convention, Section should equal Pin Group and each physical pin should appear in only one group.
- Exposed pad / pin 65 is named
AVSS_2. The datasheet package land pattern labels exposed pad 65 but the pin-function table does not explicitly call it AVSS or state an electrical net. Safer metadata would name itPowerPAD,EP, orTHERMAL_PADand describe it as the exposed thermal pad unless TI documentation confirms it must connect to AVSS.
Symbol geometry observation:
- The terminal ordering visually follows the package top-view order: pins 1-16 on the left side, 17-32 on the bottom, 33-48 on the right, and 49-64 on the top. This is consistent with the TI top-view pinout.
Footprint Cross-Check
The current footprint does not match the TI HTQFP/PAP land pattern.
Current footprint observations:
- 65 pad nodes exist.
- Every pad is at position
(0, 0, 0). - Every pad size is approximately
0.0016 mm x 0.0016 mm x 0.0016 mm. - Every pad is circular.
- No pad pitch, no side placement, no rectangular gull-wing pads, and no exposed thermal pad geometry are defined.
- Footprint package size is
0 x 0.
Datasheet land-pattern expectations:
- 64 signal pads around a 10 mm x 10 mm HTQFP body.
- 0.5 mm pitch.
- Example board layout shows 64 pads about 1.5 mm x 0.3 mm.
- Overall land-pattern envelope around 11.4 mm x 11.4 mm.
- Exposed PowerPAD / thermal pad shown as pad 65, with example exposed metal around 6.5 mm x 6.5 mm and optional thermal vias depending application.
- TI notes that the package is designed to be soldered to a thermal pad and references SLMA002 / SLMA004 PowerPAD guidance.
Result: Critical footprint mismatch. The current footprint is not manufacturable for BQ79656PAPRQ1 and should be rebuilt before using this part in a PCB.
Overall Result
- Metadata: mostly correct, but package metadata is missing and the set datasheet URL is an uploaded copy rather than the official TI link.
- Symbol pin names/numbers: pins 1-64 match the datasheet.
- Symbol pin metadata: incomplete; pin descriptions, pin types, groups, and sections should be populated from the datasheet.
- Pin 65: should be treated carefully as the exposed PowerPAD/thermal pad, not as a normal AVSS duplicate unless TI confirms the electrical connection.
- Footprint: critical mismatch; current pad geometry is placeholder/default and does not implement the 64-pin HTQFP PAP0064F land pattern.
Recommended Fixes
- Rebuild the footprint as HTQFP-64 PAP0064F: 0.5 mm pitch, 64 rectangular gull-wing pads, 10 mm x 10 mm body, and a properly sized exposed PowerPAD/thermal pad.
- Rename terminal 65 from
AVSS_2toPowerPAD,EP, orTHERMAL_PAD, and add a datasheet-backed description. - Populate each terminal's Pin Description and Pin Type from Table 5-1 of the datasheet.
- Add broad Pin Group and Section metadata, keeping Section equal to Pin Group.
- Add or correct Package metadata to
HTQFP-64 (PAP), PAP0064F PowerPAD TQFP. - Consider replacing the current uploaded Datasheet URL with the official TI URL
https://www.ti.com/lit/gpn/BQ79656-Q1for traceability.
Sources Reviewed
Current Part Metadata
Official Datasheet Key Specifications
Pinout Cross-Check
Symbol / Terminal Metadata Findings
Footprint Cross-Check
Overall Result
Recommended Fixes
