Project Startup Help
Thought for 5 mins 28 sec
They’re still running. I’ll check final status once more and then give you the project links and current state so you’re not blocked waiting.
Worked for 21 sec
Created two separate PCB projects and started the split/place work in each:
- TX board: /timbochu/munkrofon-tx-pcb
- RX board: /timbochu/munkrofon-rx-pcb
Current status:
- TX clone: RX circuitry removed, board-mounted XLR replaced with compact XLR harness pads, 25 × 80 mm / 4-layer target set, placement still running.
- RX clone: TX circuitry removed, board-mounted XLR replaced with compact XLR harness pads, 25 mm width / 4-layer target set, placement still running.
- Master project remains unchanged as the system/reference design.
Open item:
- Both split-placement tasks are still running; they exceeded the wait window but are actively working on non-RF placement and verification.
Next step:
- Open each project link later to review the completed thread result, or ask me to check their status again.
Check split projects
Check TX status
Check RX status
Fix failed split tasks
Compare split BOMs
Refine this doc
Ask about this doc
Engineering Review Report — Phase 2
Project: Munkrofon
Baseline: Prototype Revision A schematic, ERS v1.0, Phase 2 Engineering Review Plan
Status: Review deliverable 1 of 6
Schematic/layout changes made in this step: None
Baseline: Prototype Revision A schematic, ERS v1.0, Phase 2 Engineering Review Plan
Status: Review deliverable 1 of 6
Schematic/layout changes made in this step: None
Executive Summary
Prototype Revision A is a credible exploratory architecture, but it is not ready for PCB layout. The audio architecture is directionally strong, but the largest risks are RF vendor dependency, provisional codec/RF clocking, the 3.3 V power strategy from a 1S battery, split-rail power complexity, incomplete XLR abuse/RFI protection, and unresolved ERC missing-power findings.
Recommended next step: complete the component comparison matrix and power-state analysis before approving any schematic changes.
Review Legend
- Keep: Current choice is broadly appropriate.
- Modify: Keep the general direction but change support circuitry, requirements, or implementation details.
- Replace: Current choice should likely be changed before layout.
- Conditional keep: Current choice may remain only if named dependencies close.
1. RF Module
Table
| Field | Review |
|---|---|
| Current implementation | Two provisional RTX1090R1 modules: U1 transmitter, U7 receiver. RF-to-codec nets are explicitly marked provisional. ANT1/ANT2 connect to placeholder antenna components AE1–AE4. |
| Why selected | Public RTX/RMED material positions RTX1090/R1 + Sheerlink/Sheersound for professional microphones/stage equipment with low single-digit to <7 ms-class latency claims. |
| Strengths | Best aligned with professional low-latency DECT goal; compact module; DECT band avoids Bluetooth; module approach reduces discrete RF risk; replaceable interface boundary is already present. |
| Weaknesses | Official integration package missing; RF-to-codec pin mapping not public; antenna layout not valid; SDK/licensing/production programming/test modes unknown; modular approval conditions unknown; ERC flags several RTX output/optional pins as missing power. |
| Alternatives | RTX/RMED official reference design; Renesas DA14AVDDECT-SF01 as better public-documentation fallback; reject SC14WAMDECT for new design; 2.4 GHz RTX1290 only if DECT preference relaxes. |
| Recommendation | Conditional keep / modify. Keep RTX1090R1 as leading candidate but do not freeze RF layout until official RTX/RMED package is obtained. |
| Confidence | Low until vendor package, lifecycle, SDK, antenna and codec-interface evidence are obtained. |
2. Antenna / RF Layout
Table
| Field | Review |
|---|---|
| Current implementation | NN02-224 wideband chip antennas are placeholders only. |
| Why selected | Clears schematic antenna nets and makes RF layout dependency visible. |
| Strengths | Explicitly marks antenna nets; supports diversity intent; avoids hidden dangling RF pins. |
| Weaknesses | Not a DECT production antenna design; not RTX-approved; no matching network; no enclosure/hand-effect tuning; 25 mm form factor may make diversity spacing difficult. |
| Alternatives | RTX1x90EVK antenna layout; RTX-approved chip/flex/external antenna; single antenna if vendor confirms diversity not required. |
| Recommendation | Replace before RF layout. Use official RTX/RMED antenna/reference layout or written vendor-approved equivalent. |
| Confidence | Low. |
3. Codec / ADC / DAC
Table
| Field | Review |
|---|---|
| Current implementation | TLV320AIC3204 codec on both TX and RX. I²S-like nets and I²C control are provisionally mapped to RTX1090R1 GPIO/audio-capable pins. |
| Why selected | Flexible low-power stereo codec with ADC/DAC, 24-bit-capable digital audio interface, I²C/SPI control, and available Flux part. |
| Strengths | Capable and flexible; same part on TX/RX simplifies firmware once validated; suitable for 48 kHz-class audio architecture. |
| Weaknesses | Codec may be overfeatured for mono wireless mic use; clock master/slave relationship unresolved; MCLK source provisional; latency depends on configuration; RTX Sheerlink supported codec/interface is unknown; ERC flags internal LDO output/filter rails as missing power. |
| Alternatives | RTX/RMED recommended codec; simpler TI/Cirrus/AKM ADC/DAC pair; higher-performance pro-audio ADC/DAC if THD+N/SNR targets require; RF module integrated audio if available and adequate. |
| Recommendation | Conditional keep / modify. Keep for Rev A review, but replace if RTX/RMED specifies another codec or interface. |
| Confidence | Medium-low. |
4. Microphone Preamp
Table
| Field | Review |
|---|---|
| Current implementation | THAT1580 differential mic preamp, fixed provisional gain resistor, balanced XLR input. |
| Why selected | Professional low-noise balanced microphone preamp suitable for passive dynamic microphones and differential ADC drive. |
| Strengths | Strong professional audio candidate; good CMRR/noise architecture; balanced XLR input is correct for use case. |
| Weaknesses | Phantom-power abuse protection missing; RFI input network incomplete; gain/headroom target not defined; ±5 V rail increases power/area; high-SPL drum mic may need pad/clip strategy. |
| Alternatives | THAT1512/1510, INA217/INA163-class preamps, lower-power single-supply instrumentation/audio front-end, switchable gain/pad. |
| Recommendation | Keep, but modify. Add phantom/RFI/ESD protection, define gain/headroom, and reassess whether TX really needs ±5 V rails. |
| Confidence | Medium-high for part quality; medium for current implementation. |
5. Balanced Line Driver
Table
| Field | Review |
|---|---|
| Current implementation | THAT1646 line driver fed from RX codec line output through coupling cap, driving male XLR output. |
| Why selected | Provides true active balanced output, appropriate for professional mixer inputs. |
| Strengths | Good pro-audio part; true balanced output; Neutrik XLR is robust. |
| Weaknesses | Final output target undefined; ±5 V may be insufficient or excessive depending required headroom; no complete RFI/ESD/cable-abuse protection; pop/mute strategy not defined. |
| Alternatives | THAT1606/1646 variants, DRV134-class, fully differential op-amp such as OPA163x family, lower-power output if only mic-level output is needed. |
| Recommendation | Keep if true pro balanced line output is required; modify support rails/protection. Define output level before PCB layout. |
| Confidence | Medium. |
6. Battery Charger and Power Path
Table
| Field | Review |
|---|---|
| Current implementation | BQ24074 per unit, USB-C 5 V input, 1S Li-ion/LiPo battery connector, ~500 mA charge-current configuration, OUT system rail. |
| Why selected | Known single-cell charger with dynamic power-path management and USB-compatible current modes. |
| Strengths | Good fit for rechargeable portable device; allows operation while charging; credible vendor part; 500 mA charge target is thermally conservative. |
| Weaknesses | Linear charger heat needs calculation; TS/NTC strategy currently simplified; protected-cell vs board-level protection unresolved; ship/off mode not defined; charger noise may affect audio. |
| Alternatives | BQ24075-class variant, charger with ship mode/load disconnect, switching charger if thermal limits require, RF-module-integrated charger only if vendor recommends. |
| Recommendation | Keep, with modifications. Add real battery NTC/protection decision, off/ship-mode strategy, and charger-noise/thermal review. |
| Confidence | High. |
7. Power Path and 3.3 V Regulation
Table
| Field | Review |
|---|---|
| Current implementation | AP2112K 3.3 V LDO from BQ24074 OUT/SYS per unit. |
| Why selected | Simple low-noise 3.3 V rail for RF I/O, codec I/O, fuel gauge, and support logic. |
| Strengths | Low noise; simple; available; low component count. |
| Weaknesses | Major battery-runtime/reliability issue: 3.3 V LDO from 1S Li-ion loses regulation as battery approaches low state; may brown out before useful battery capacity is exhausted; wastes power when battery is high. |
| Alternatives | 3.3 V buck-boost; lower system rail if all parts support it; buck-boost pre-regulator plus LDO post-filter; vendor-approved direct battery/rail strategy. |
| Recommendation | Replace/re-architect before layout. Use buck-boost or lower-voltage strategy if runtime/reliability matter. AP2112K may remain as post-filter only. |
| Confidence | High. |
8. Analog Rails
Table
| Field | Review |
|---|---|
| Current implementation | TPS65131 per unit generates ±5 V rails for TX THAT1580 and RX THAT1646. |
| Why selected | THAT1580 and THAT1646 are dual-supply analog parts; split rails provide headroom from 1S battery. |
| Strengths | Enables selected pro-audio ICs; gives analog headroom; single IC produces both rails. |
| Weaknesses | Large component count; switching noise risk; layout sensitive; runtime penalty; may be unnecessary on TX; always-on rails would waste power without rail gating. |
| Alternatives | Remove TX split rails by choosing lower-power/single-supply mic front-end; keep split rail only on RX; charge pump/inverter if current allows; boosted positive rail with single-supply audio parts; post-filtering/LDOs. |
| Recommendation | Modify; possibly remove from TX. Keep RX ± rail only if output target requires it; add enable control and filtering strategy. |
| Confidence | Medium. |
9. Fuel Gauge
Table
| Field | Review |
|---|---|
| Current implementation | MAX17048 per unit on provisional I²C/control bus. |
| Why selected | Low-power 1S fuel gauge with no sense resistor; supports SOC estimate and low-battery UX. |
| Strengths | Useful for professional reliability/low-battery indication; simple gauge architecture; low quiescent current. |
| Weaknesses | Requires host firmware/UI path; adds BOM and I²C complexity; may not be useful if no display/app/status behavior exists. |
| Alternatives | Battery voltage ADC into RF module; charger status only; low-battery comparator; optional/DNP footprint. |
| Recommendation | Make optional / DNP unless host/UI confirmed. |
| Confidence | Medium. |
10. USB-C Implementation
Table
| Field | Review |
|---|---|
| Current implementation | USB-C connector per unit with CC1/CC2 pulldowns and ESD-protected D+/D− marked unused/protected. |
| Why selected | Provides modern charging input; leaves possibility for debug/update. |
| Strengths | Correct basic sink CC implementation; USB data pins are not left floating; ESD devices included. |
| Weaknesses | USB data role unresolved; VBUS fuse/load-switch/TVS strategy incomplete; shield/chassis grounding not defined; unnecessary data routing if charging-only. |
| Alternatives | Charge-only USB-C with minimal D+/D− handling; full USB debug/update route to RF module; add VBUS load switch/polyfuse/TVS. |
| Recommendation | Modify. Decide charge-only versus debug/update before layout; add VBUS protection and shield/chassis plan. |
| Confidence | High. |
11. Clocking
Table
| Field | Review |
|---|---|
| Current implementation | Provisional codec MCLK/BCLK/WCLK/DIN/DOUT mapping to RTX1090R1 pins. |
| Why selected | Public RTX material confirms digital audio capability but not exact mapping; Rev A needed explicit interface nets. |
| Strengths | Clock/audio nets are visible and isolated; easy to revise when vendor mapping arrives. |
| Weaknesses | Clock master/slave relationship unknown; MCLK source unknown; jitter and sample-rate behavior unknown; current mapping may not work with Sheerlink firmware. |
| Alternatives | Vendor-recommended codec and clock tree; RF module as master; codec as master if supported; external low-jitter oscillator if required. |
| Recommendation | Modify / unresolved. Do not layout final audio-clock routing until RTX/RMED confirms clocking. |
| Confidence | Low. |
12. Audio Architecture
Table
| Field | Review |
|---|---|
| Current implementation | Balanced mic input → THAT1580 → TLV320AIC3204 → RTX1090R1 → RTX1090R1 → TLV320AIC3204 → THAT1646 → balanced XLR. |
| Why selected | Separates professional analog audio conditioning from RF module; preserves true balanced output and replaceable RF boundary. |
| Strengths | Architecturally sound for pro audio; modular; avoids pseudo-balanced output; leaves RF module replaceable. |
| Weaknesses | More complex than required if RF vendor supplies full audio reference; two codecs and split rails increase area/current; latency depends on codec/RF/firmware integration. |
| Alternatives | Vendor reference codec/audio design; simpler mono TX/RX ADC/DAC; RF module integrated codec path if adequate. |
| Recommendation | Keep architecture concept, modify implementation after component matrix. |
| Confidence | Medium. |
13. Overall Power Architecture
Table
| Field | Review |
|---|---|
| Current implementation | 1S Li-ion/LiPo, USB-C charger/power path, 3.3 V LDO, ±5 V analog rails, per-unit fuel gauge. |
| Why selected | Supports portable rechargeable TX/RX with pro analog headroom. |
| Strengths | Complete power tree exists; charger/power path is credible; analog rails support selected ICs. |
| Weaknesses | Likely over-complex and inefficient; AP2112K dropout limits runtime; split rails may dominate load; no power-state gating; battery protection/off-state unresolved. |
| Alternatives | Buck-boost 3.3 V, optional split rails, rail gating, remove fuel gauge, lower-power audio ICs. |
| Recommendation | Modify before layout. Perform power-state analysis and updated runtime estimates before approving next schematic revision. |
| Confidence | High. |
14. Manufacturability and Serviceability Review
Table
| Topic | Findings |
|---|---|
| Component count | 94 components; likely high for target form factor. Review removal of optional fuel gauges, TX split rail, unused USB data, and redundant passives. |
| Generic passives | Values exist, but production packages/voltage/current/power/tolerance/dielectric ratings still need closure. |
| Assembly | Multiple QFN/WSON/LGA-style parts require controlled assembly and inspection. |
| Testability | Test-point plan still needed for rails, battery, charger status, codec clocks, RF UART/SWD/USB, audio in/out. |
| Serviceability | Battery connector is serviceable; USB/XLR need mechanical strain-relief strategy; RF module replacement/rework will be difficult. |
15. Current Automated Check Context
Current queried ERC status shows remaining Missing Power findings only. No floating-pin or single-pin-net issues were present in the latest queried set.
Remaining missing-power items are mainly:
- Rails fed by BQ24074 OUT/SYS not recognized as power sources by ERC.
- TLV320AIC3204 internal-LDO/filter rails flagged as undriven.
- RTX1090R1 pins labeled by public data as outputs/optional supplies but modeled as power pins in the provisional component.
- THAT1646 VCC on generated RX_5VA not recognized as driven.
These must be classified and resolved/justified before layout.
16. Keep / Modify / Replace Summary
Table
| Subsystem | Recommendation | Confidence |
|---|---|---|
| RTX1090R1 RF platform | Conditional keep / modify | Low |
| Antenna placeholders | Replace before RF layout | Low |
| TLV320AIC3204 codec | Conditional keep / modify | Medium-low |
| THAT1580 mic preamp | Keep, modify protection/gain/rails | Medium-high |
| THAT1646 balanced driver | Keep if output target justifies it | Medium |
| BQ24074 charger/power path | Keep, modify thermal/protection/off-state | High |
| AP2112K 3.3 V LDO from 1S | Replace / re-architect | High |
| TPS65131 ±5 V rails | Modify; possibly remove from TX | Medium |
| MAX17048 fuel gauge | Optional/DNP unless host/UI confirmed | Medium |
| USB-C implementation | Modify protection/role/shielding | High |
| Clocking | Modify / unresolved | Low |
| Audio architecture | Keep concept, review implementation | Medium |
| Overall power architecture | Modify before layout | High |
17. Highest-Priority Changes Before PCB Layout
- Obtain RTX/RMED integration package: hardware guide, schematic/layout/stackup/BOM, antenna, SDK, codec clocking, latency, and test modes.
- Rework 3.3 V power strategy; do not rely on AP2112K directly from 1S battery unless dropout/runtime loss is accepted.
- Define RX output level/headroom target.
- Reassess whether TX needs ±5 V analog rails.
- Add XLR phantom-power abuse, ESD, RFI, and pin-1/chassis grounding strategy.
- Decide USB role: charge-only versus debug/update.
- Make MAX17048 optional/DNP unless firmware/UI path is confirmed.
- Resolve or explicitly justify remaining ERC missing-power findings.
- Lock passive packages/ratings.
- Add test-point strategy.
18. Overall Recommendation
Proceed with Rev A only as an exploratory engineering prototype. Do not begin PCB layout yet. The next deliverables should be, in order:
- Component Comparison Matrix.
- Power-State Analysis and runtime estimates.
- System Design Description.
- Prioritized Schematic Change List.
After those are complete, request approval before applying schematic changes.
Executive Summary
Review Legend
1. RF Module
2. Antenna / RF Layout
3. Codec / ADC / DAC
4. Microphone Preamp
5. Balanced Line Driver
6. Battery Charger and Power Path
7. Power Path and 3.3 V Regulation
8. Analog Rails
9. Fuel Gauge
10. USB-C Implementation
11. Clocking
12. Audio Architecture
13. Overall Power Architecture
14. Manufacturability and Serviceability Review
15. Current Automated Check Context
16. Keep / Modify / Replace Summary
17. Highest-Priority Changes Before PCB Layout
18. Overall Recommendation
