LA1266

No.2291-3/11

How to use LA1266

1. LED driver, muting drive output, stop signal(SD).

• For LED drive, muting drive output, stop signal, the output at pin 8 is used.

• Voltage on pin 8, when tuned, turns from "H" to "L" . (Active-low)

• Signal bandwidth at pin 8

– For AM, the bandwidth depends on the C.F(BFU450CN) at pin 14.

If a capacitor is connected in place of the C.F, the bandwidth will get wider.

– For FM, the bandwidth depends on the resistance across pins 9 and 22.

If the resistance is increased, the bandwidth will get narrower.

R=15k

Ω makes the bandwidth approximately 110kHz.

• Sensitivity adjustment of LED, muting, stop signal

– For FM, the semifixed variable resistor across pin 16 and GND is used.

– For AM, the semifixed variable resistor across pin 17 and GND is used.

The relation (for AM,FM) between signal meter voltage and input voltage with the resistance of the semifixed

variable resistor as a parameter is shown below.

FM S Meter Voltage

AM S Meter Voltage

Unit (capacitance : F)

Resisitance across Pins 9 and 22 – k

Ω

IF input voltage – dBµ

Antenna input voltage – dB/m