AN738

2

Rev. 0.2

2. Frequency Band Definition and Selection

Eighteen FM bands, five AM bands, and eighteen SW bands are defined for Si4825/36-A. In FM band, the parts

also offer two de-emphasis selections and two stereo LED indication threshold selections. In SW band, the part

offers 18 wide bands or 18 narrow bands. This section shows the detailed band definition and selection

information.

2.1. Band Definition

For the Si4825/36-A, the FM band definition is a combination of frequency range, de-emphasis and stereo LED

indication threshold (Si4836-A only). Customers should choose the band according to the frequency range, as well

as de-emphasis setting and stereo LED indication requirements. For AM and SW, simply choose the band

according to the frequency range desired.

Table 2. Band Sequence Definition for Si4836-A

Band

Number

Band

Name

Band Frequency Range

De-emphasis

(FM)

Channel

Space (AM)

Stereo LED on Conditions

Total R

to GND

(k

, 1%)

Band1

FM1

87–108 MHz

50 µs

Separation = 6 dB, RSSI = 20

47

Band2

FM2

87–108 MHz

50 µs

Separation = 12 dB,

RSSI = 28

57

Band3

FM3

87–108 MHz

75 µs

Separation = 6 dB, RSSI = 20

67

Band4

FM4

87–108 MHz

75 µs

Separation = 12 dB,

RSSI = 28

77

Band5

FM5

86.5–109 MHz

50 µs

Separation = 6 dB, RSSI = 20

87

Band6

FM6

86.5–109 MHz

50 µs

Separation = 12 dB,

RSSI = 28

97

Band7

FM7

87.3–108.25 MHz

50 µs

Separation = 6 dB, RSSI = 20

107

Band8

FM8

87.3–108.25 MHz

50 µs

Separation = 12 dB,

RSSI = 28

117

Band9

FM9

87.3–108.25 MHz

75 µs

Separation = 6 dB, RSSI = 20

127

Band10

FM10

87.3–108.25 MHz

75 µs

Separation = 12 dB,

RSSI = 28

137

Band11

FM11

76–90 MHz

50 µs

Separation = 6 dB, RSSI = 20

147

Band12

FM12

76–90 MHz

50 µs

Separation = 12 dB,

RSSI = 28

157

Band13

FM13

64–87 MHz

50 µs

Separation = 6 dB, RSSI = 20

167

Band14

FM14

64–87 MHz

50 µs

Separation = 12 dB,

RSSI = 28

177

Band15

FM15

76–108 MHz

50 µs

Separation = 6 dB, RSSI = 20

187

Band16

FM16

76–108 MHz

50 µs

Separation = 12 dB,

RSSI = 28

197