Philips Semiconductors

Product specification

SA625

High performance low power mixer FM IF system

with high-speed RSSI

1997 Nov 07

4

AC ELECTRICAL CHARACTERISTICS

level = -45dBm; FM modulation = 1kHz with

±8kHz peak deviation. Audio output with C-message weighted filter and de-emphasis capacitor.

Test circuit Figure 3. The parameters listed below are tested using automatic test equipment to assure consistent electrical characterristics.

The limits do not represent the ultimate performance limits of the device. Use of an optimized RF layout will improve many of the listed parame-

ters.

LIMITS

SYMBOL

PARAMETER

TEST CONDITIONS

SA625

UNITS

MIN

TYP

MAX

Mixer/Osc section (ext LO = 300mV)

Input signal frequency

500

MHz

Crystal oscillator frequency

150

MHz

Noise figure at 45MHz

5.0

dB

Third-order input intercept point

f1 = 45.0; f2 = 45.06MHz

-10

dBm

Conversion power gain

Matched 14.5dBV step-up

10

13

15

dB

50

Ω source

-1.7

dB

RF input resistance

Single-ended input

3.0

4.7

k

Ω

RF input capacitance

3.5

4.0

pF

Mixer output resistance

(Pin 20)

1.25

1.5

k

Ω

IF section

IF amp gain

50

Ω source

39.7

dB

Limiter gain

50

Ω source

62.5

dB

Test at Pin 18

-113

dBm

AM rejection

80% AM 1kHz

29

34

43

dB

15nF de-emphasis

80

150

260

150pF de-emphasis

480

mV

SINAD sensitivity

RF level -118dB

16

dB

THD

Total harmonic distortion

-34

-42

dB

S/N

Signal-to-noise ratio

No modulation for noise

73

dB

IF level = -118dBm

0

160

650

mV

IF level = -68dBm

1.9

2.5

3.1

V

IF level = -18dBm

4.0

4.8

5.6

V

IF frequency = 455kHz

RF level = -56dBm

1.2

µs

IF RSSI output rise time

RF level = -28dBm

1.2

µs

(10kHz pulse, no 455kHz filter)

IF frequency = 10.7MHz

(no RSSI bypass capacitor)

RF level = -56dBm

1.2

µs

RF level = -28dBm

1.1

µs

IF frequency = 455kHz

RF level = -56dBm

2.1

µs

IF RSSI output fall time

RF level = -28dBm

7.6

µs

(10kHz pulse, no 455kHz filter)

IF frequency = 10.7MHz

(no RSSI bypass capacitor)

RF level = -56dBm

2.0

µs

RF level = -28dBm

7.3

µs

RSSI range

90

dB

RSSI accuracy

+1.5

dB

IF input impedance

1.40

1.6

k

Ω

IF output impedance

0.85

1.0

k

Ω

Limiter intput impedance

1.40

1.6

k

Ω

Limiter output impedance

300

Ω

Limiter output level with no load

280