3PEAK (688536) has introduced the TPAFEA006, a highly integrated analog front‑end (AFE) chip purpose‑built for CPO (co‑packaged optics) and NPO (near‑package optics) modules in data centers. The device packs 32‑channel heater bias DACs, 12‑channel VDACs, 128‑channel monitoring ADC, and 72‑channel mPD current‑sense inputs – all in a compact 2.95×7.95mm WLCSP‑168 package, meeting the tight PCB layout constraints of CPO designs.
Heater bias section: 32 channels, each configurable for current mode (0‑30mA) or voltage mode (±40mA max) , covering MZM modulator bias control. Each channel supports dither injection for fast operating‑point lock. Four independent power groups enable flexible system matching. Low‑headroom design drops only 150mV at 30mA (current mode) and 300mV at 20mA (voltage mode), cutting system power. Output voltage read‑back is included for real‑time monitoring.
12‑channel VDAC: 2.7‑5.5V supply, output ranges 0‑2.5V or 0‑5V. Each channel sources/sinks up to 50mA with 200mV headroom at 20mA load – eliminating external buffers. Output read‑back is also provided.
128‑channel system monitor: Built‑in 12‑bit 500kSPS SAR ADC, with 80 external inputs (72 mPD current + 8 general‑purpose ADC) and 48 internal self‑check channels monitoring heater voltages, VDAC outputs, and core power supplies – enabling full‑link status tracking.
72‑channel mPD front‑end: Integrated TIA for photodiode current sensing (64 TX + 8 RX), supports common‑cathode and common‑anode configurations, with programmable termination voltage. Seven current ranges cover ±125µA to ±7mA – a single chip handles full silicon‑photonic module optical power acquisition.
Additional resources: 12 GPIO, over‑temperature alert and auto‑shutdown, I²C (1MHz) and SPI (20MHz) auto‑detection, –40°C to +125°C operation.
Complete CPO solution: 32 heater channels directly bias MZM modulators; 12 VDACs provide Vcom/Vbias for PIC; 64 channels monitor TX optical power; 8 channels handle RSSI; and 8 channels cover incident power – forming a full closed‑loop optical control system.
ICgoodFind Takeaway:
The TPAFEA006 demonstrates that high‑integration AFE design is key to enabling compact CPO modules. For silicon‑photonics designers, this chip could simplify board layout and accelerate time‑to‑market.
