Texas Instruments DAC5652, Руководство пользователя

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Circuit Function
2-3 Circuit Description
Table 2−2. Input Connector J10
J10 Pin No. Description J10 Pin No. Description
1 Port 2 Data Bit 13 (MSB) 18 GND
2 GND 19 Port 2 Data Bit 4
3 Port 2 Data Bit 12 20 GND
4 GND 21 Port 2 Data Bit 3
5 Port 2 Data Bit 11 22 GND
6 GND 23 Port 2 Data Bit 2
7 Port 2 Data Bit 10 24 GND
8 GND 25 Port 2 Data Bit 1
9 Port 2 Data Bit 9 26 GND
10 GND 27 Port 2 Data Bit 0
11 Port 2 Data Bit 8 28 GND
12 GND 29
13 Port 2 Data Bit 7 30 GND
14 GND 31
15 Port 2 Data Bit 6 32 GND
16 GND 33
17 Port 2 Data Bit 5 34 GND
2.2.3 Output Data
The DAC5672/62/52 EVM can be configured to drive a doubly terminated
50-
Ω
cable or provide unbuffered differential outputs.
2.2.3.1 Transformer Coupled Signal Output
The factory-set configuration of the demonstration board provides the user
with a single-ended output signal at SMA connector J5. The DAC5672/62/52
is configured to drive a doubly terminated 50-
Ω
cable using a 4:1 impedance
ratio transformer and the center tap of T1 and T2 connected to ground. When
using a 1:1 impedance ratio transformer, configure the EVM per Table 2−3.
Table 2−3. Transformer Output Configuration
Configuration Components Installed
†
Components Not Installed
1:1 Impedance ratio transformer R3−R8, T1, T2 R9, R11, C7, C8
4:1 Impedance ratio transformer R3 (100), R4 (100), R5 (100),
R6 (100), T1 (4:1), T2 (4:1)
R7, R8, R9, R11, C7, C8
†
All component values are per the Schematic, except where shown in parenthesis.
2.2.3.2 Unbuffered Differential Output
To provide unbuffered differential outputs, the EVM must be configured as
follows: Remove R7, R8, T1, and T2; Install R10, R12, R15, R18, R25, R29,
J5, and J8.