The MAX7461 is a single-channel loss-of-sync alarm (LOS) that provides composite video sync detection in NTSC, PAL, and SECAM standard-definition television (SDTV) systems. MAX7461's advanced detection circuitry delivers robust performance by preventing false loss-of-sync alarms due to noise. The device accepts an AC-coupled composite (CVBS), luma (Y), or any other video signal with sync, and outputs a logic-level signal. The open-drain LOS output is low when no sync is detected and high impedance when sync is detected. The device operates from a single +5V supply. The MAX7461 is available in a 5-pin SOT23 package and is specified for operation over the -40°C to +85°C temperature range.
The MAX7461 loss‑of‑sync alarm monitors composite video signals (CVBS, Y or any video with sync) and provides an open‑drain LOS output that is low when sync is absent and high‑impedance when sync is present. It operates from a single +5 V supply and is offered in a 5‑pin SOT‑23 package.
Typical applications include security systems, automotive rear‑seat entertainment, and consumer electronics. The device includes an input clamp, low‑pass filter, and a programmable LOS detector with typical detect and release times of 3.4 ms and 2.2 ms respectively. A 1 kΩ pull‑up resistor is required on the LOS output.
| Supply Voltage (VCC) | 5.0 V (typ) |
|---|---|
| Supply Current (IC) | 2.2 mA (typ) |
| Package | 5‑pin SOT‑23 |
The MAX7461 provides an open‑drain LOS output that is low when no sync is detected and high‑impedance when sync is present.
The device operates from a single +5 V supply.