LA75676VA

No.7868-9/10

S1. SIF limiting sensitivity • • • • [Vi (lim)]

1. External AGC. Apply the VCC voltage to the IF AGC (pin 17).

2. fs = 4.5MHz, fm = 400Hz,

∆F = ±25kHz (SIF input)

3. Set the SIF input level to 100mVrms and measure the value at test point D at that time. • • V1

4. Lower the SIF input level and measure the input level such that V1 is down by 3dB.

S2, S4. FM detection output voltage, total harmonic distortion • • • • [Vo(FM), THD]

1. External AGC. Apply the VCC voltage to the IF AGC (pin 17).

2. fs = 4.5MHz, fm = 400Hz,

∆F = ±25kHz (SIF input, Vi = 100mVrms)

3. Measure the FM detection output voltage and total harmonic distortion at test point D.

S3. AM rejection ratio • • • • [AMR]

1. External AGC. Apply the VCC voltage to the IF AGC (pin 17).

2. fs = 4.5MHz, fm = 400Hz, AM = 30% (SIF input, Vi = 90dB

µV)

3. Measure the output voltage at test point D. • • • VAM

4. AMR = 20log

VO (DET)

VAM

dB

S5. SIF signal-to-noise ratio • • • • [S/N]

1. External AGC (V17 = VCC)

2. fs = 4.5MHz, no modulation, Vi = 100mVrms

3. Measure the output voltage at test point D. • • • • Vn

4. S/N = 20log

VO (DET)

Vn

dB

S6. 4.5MHz output level • • • • [S/N]

1. External AGC (V17 = VCC)

2. fs = 4.5MHz, no modulation, Vi = 10mVrms

3. Measure the output voltage at test point E. • • • • Vsout

Note 1. Unless specified otherwise, when measuring VIF, apply the VCC voltage to the AGC and adjust the VCO coil

so that it oscillates at 45.75MHz.

Note 2. Unless specified otherwise, switch SW1 must be in the on position.