U2731B-NFNG1 Atmel, U2731B-NFNG1 Datasheet - Page 11

• Manufacturer Part Number: U2731B-NFNG1
• Description: IC FRONT-END DAB 8.5V 44SSOP
• Manufacturer: Atmel

Specifications of U2731B-NFNG1

• Mfg Application Notes: U2731B
• Package / Case: 44-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Frequency: -
• Rf Type: -

Simple Two-wire Bus
Interface
Table 3. Simple Two-wire Bus Instruction Codes
Simple Two-wire Bus
Functions
4671C–DAB–06/04
Description
Address
A byte 1
A byte 2
A byte 3
B byte 1
B byte 2
B byte 3
C byte 1
C byte 2
C byte 3
D byte 1
D byte 2
D byte 3
MSB
SWA
CC7
CA7
CB7
r
r
1
0
X
X
0
1
1
7
3
Via its two-wire bus interface, various functions can be controlled by a microprocessor.
These functions are outlined in the following table “Simple Two-wire Bus Instruction
Codes” on page 11 and in the section “Simple Two-wire Bus Functions” on page 11. The
programming information is stored in a set of internal registers. By means of the Pin
ADR, two different two-wire bus addresses can be selected as described in the section
“Electrical Characteristics”. In Figure 6 on page 19, the two-wire bus timing parameters
are explained, Figure 7 on page 20 shows a typical two-wire bus pulse diagram.
AS1
n
r
TAi
TBi
TCi
CAi, CBi, CCi
OS
T
TRI
i
i
SWB
CC6
CA6
CB6
X
X
r
r
1
0
1
0
1
6
2
Define the setting of the three D/A converters A, B and C (i = 0, ..., 7)
Defines the two-wire bus address
Deffective scaling factor (SFeff) of the main divider
Scaling factor (SF
Define the setting of a 4-bit D/A converter controlling the threshold,
th1, of the RF AGC to adjust the controlled output power
Define the setting of a 4-bit D/A converter controlling the threshold,
th2, which determines the activation voltage for the internal RF AGC
Define the setting of a 4-bit D/A converter controlling the threshold,
th3, of the IF AGC to adjust the output power
OS = HIGH switches off the tuning output
For T = HIGH, reference signals describing the output frequencies of
the reference divider and programmable divider are monitored at
SWA (reference divider) and SWC (programmable divider).
TRI = HIGH switches off the charge pump
SWC
CC5
CA5
CB5
n
n
X
X
r
r
X
0
0
11
5
1
5
CC4
CA4
CB4
n
OS
n
X
r
r
r
X
X
0
10
8
4
0
4
ref,eff
) of the reference divider SF
CC3
TB3
TC3
CA3
CB3
TA3
M3
n
n
X
X
0
T
9
3
AS1
TC2
CA2
CB2
CC2
TB2
TA2
TRI
M2
n
n
n
X
14
8
2
ref,eff
I100
CC1
TB1
TC1
CA1
CB1
TA1
n
M1
n
n
SF
X
0
13
7
1
eff
= 4
U2731B
=
n
r
i
i
LSB
CC0
TC0
CA0
CB0
TB0
TA0
n
I50
M0
2
n
n
X
0
12
i
6
0
2
i
11