Product Introduction
When cable modems, set-top boxes, or home networking devices stop powering on, reboot unexpectedly, or lose connectivity, the issue is often caused by a failed or unstable power adapter. The LEI MT20-21120-A00F (P/N 503913-004) 12V 750mA adapter is designed to deliver stable low-power DC output, ensuring reliable operation for broadband and digital TV equipment in home environments.
Application Scenarios
- Cable broadband modems (Motorola / ARRIS compatible systems)
- Digital TV set-top boxes and IPTV receivers
- Home networking gateways and routers (12V low-power models)
- ISP-provided customer premise equipment (CPE)
- Replacement for failed 12V 750mA wall adapters
Technical Specifications
| Brand | LEI (Leader Electronics Inc.) |
| Model | MT20-21120-A00F |
| Part Number | 503913-004 |
| Output Voltage | 12V DC |
| Output Current | 750mA |
| Power Rating | 9W |
| Connector Type | 5.5mm x 2.5mm Barrel Plug |
| Polarity | Center Positive |
| Input | 100–240V AC 50/60Hz |
| Condition | Replacement Power Adapter |
OEM Replacement Compatibility
- Motorola SurfBoard modem series (SB5100 / SB6121 / SB6141)
- Cable TV digital receivers (DCT / DTA series)
- ISP broadband modem power systems
- LEI MT20-21120-A00F / 503913-004 adapter series
- 12V 750mA set-top box devices using 5.5mm x 2.5mm input
FAQ
Q1: Can I use a higher amp adapter?
A: Yes. Higher current (e.g., 1A or 2A) is safe as long as voltage remains 12V and connector matches.
Q2: Is this compatible with routers?
A: Only routers requiring 12V 750mA or similar low-power specification.
Q3: What happens if voltage is wrong?
A: Incorrect voltage may damage modem or set-top box electronics. Always match 12V exactly.
