The MAX7443/MAX7444 are low-cost, triple-channel video reconstruction filters for S-video and CVBS video signals. These devices are ideal for anti-aliasing and DAC smoothing video applications such as set-top boxes, DVD players, hard-disk recorders (HDRs), and personal video recorders. They are optimized for NTSC, PAL, and standard-definition digital TV (SDTV) video systems. Each channel consists of a lowpass filter and an adjustable-gain output buffer capable of driving two standard 150Ω video loads. The output buffers can drive either an AC or a DC load such that the blanking level voltage after the backmatch resistor is less than 1V. The Y and C video inputs are summed to produce the composite video output. The MAX7444 offers high-frequency boost to improve picture sharpness. The MAX7443 has a maximum flat-frequency response. The MAX7443/MAX7444 are available in a tiny 8-pin thin QFN and an 8-pin SO package with exposed pad, and are fully specified over the -40°C to +85°C extended temperature range.
The MAX7443 and MAX7444 are triple‑channel video reconstruction filters designed for NTSC, PAL and SDTV systems. Each channel includes a low‑pass filter and an adjustable‑gain output buffer that can drive two 150 Ω video loads, with a blanking level below 1 V. The MAX7444 adds a high‑frequency boost for improved picture sharpness, while the MAX7443 provides a flat‑frequency response.
These devices are supplied in 8‑pin thin QFN or 8‑pin SO packages, operate over –40 °C to +85 °C, and require a single +5 V supply. Gain can be set to 6 dB, 9.5 dB or 12 dB via the GSET pin, and the output can drive either AC‑ or DC‑coupled loads.
| Supply Voltage Range | 4.75 V – 5.25 V |
|---|---|
| Supply Current (no load) | 88 mA – 110 mA |
| Operating Temperature Range | -40 °C to +85 °C |
| Stopband Attenuation | 41 dB (typ) at 27 MHz |
| Gain Settings | 6 dB, 9.5 dB, 12 dB (selectable via GSET pin) |
| Output Load Capability | Drives two 150 Ω video loads per channel |
| Blanking Level Voltage | < 1 V |
The devices operate from a single +5 V supply with a permissible range of 4.75 V to 5.25 V.
Each channel can drive two standard 150 Ω video loads.
The output buffer gain can be set to 6 dB, 9.5 dB, or 12 dB via the GSET pin.
They are fully specified over –40 °C to +85 °C.