Datasheet

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DEVICE PROGRAMMING MODES
USING SERIAL INTERFACE PROGRAMMING ONLY
USING PARALLEL INTERFACE CONTROL ONLY
(3/8) AVDD
(3/8) AVDD
ToParallelPin
(SCLK,SDATA,SEN)
3R
AVDD
AVDDGND
3R
2R
(5/8) AVDD
(5/8) AVDD
GND
ADS6145, ADS6144
ADS6143, ADS6142
SLWS198B – JULY 2007 – REVISED MARCH 2008
The ADS614X have several features that can be easily configured using either parallel interface control or serial
interface programming.
To program using the serial interface, the internal registers must first be reset to their default values, and the
RESET pin must be kept low. In this mode, SEN, SDATA, and SCLK function as serial interface pins and are
used to access the internal registers of the ADC. The registers are reset either by applying a pulse on the
RESET pin or by a high setting on the <RST> bit (D4 in register 0x00). The Serial Interface section describes
register programming and register reset in more detail.
To control the device using the parallel interface, keep RESET tied high (AVDD). Now SEN, SCLK, SDATA, and
PDN function as parallel interface control pins. These pins can be used to directly control certain modes of the
ADC by connecting them to the correct voltage levels (as described in Table 1 to Table 3 ). There is no need to
apply a reset pulse.
Frequently used functions are controlled in this mode — standby, selection between LVDS/CMOS output format,
internal/external reference, and 2s complement/straight binary output format.
Figure 4. Simple Scheme to Configure Parallel Pins
DESCRIPTION OF PARALLEL PINS
Table 1. SCLK (Analog Control Pin)
SCLK DESCRIPTION
0 Internal reference and 0 dB gain (full-scale = 2 V
PP
)
(3/8) AVDD External reference and 0 dB gain (full-scale = 2 V
PP
)
(5/8) AVDD External reference and 3.5 dB coarse gain (full-scale = 1.34 V
PP
)
AVDD Internal reference and 3.5 dB coarse gain (full-scale = 1.34 V
PP
)
Table 2. SEN (Analog Control Pin)
SEN DESCRIPTION
0 2s Complement format and DDR LVDS interface
(3/8) AVDD Straight binary format and DDR LVDS interface
(5/8) AVDD Straight binary and parallel CMOS interface
AVDD 2s Complement format and parallel CMOS interface
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Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142