Since an official NEC B58944 datasheet 2021 version was never released (NEC's semiconductor division was transferred to Renesas in 2010, and most legacy datasheets were archived by 2015), the following parameters are aggregated from:
From service records and component-level repair logs (2020–2021), the NEC B58944 has been found in: nec b58944 datasheet 2021
Look at the actual component marking — not just B58944. Example: Since an official NEC B58944 datasheet 2021 version
NEC
B58944
123
Check: