AD7328BRUZ Ver la hoja de datos (PDF) - Analog Devices
Número de pieza
componentes Descripción
fabricante
AD7328BRUZ Datasheet PDF : 36 Pages
| |||
AD7328
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
CS 1
20 SCLK
DIN 2
19 DGND
DGND 3
AGND 4
REFIN/OUT 5
VSS 6
VIN0 7
VIN1 8
VIN4 9
VIN5 10
AD7328
TOP VIEW
(Not to Scale)
18 DOUT
17 VDRIVE
16 VCC
15 VDD
14 VIN2
13 VIN3
12 VIN6
11 VIN7
Figure 3. TSSOP Pin Configuration
Table 5. Pin Function Descriptions
Pin No.
Mnemonic Description
1
CS
Chip Select. Active low logic input. This input provides the dual function of initiating conversions on
the AD7328 and frames the serial data transfer.
2
DIN
Data In. Data to be written to the on-chip registers is provided on this input and is clocked into the
register on the falling edge of SCLK (see the Registers section).
3, 19
DGND
Digital Ground. Ground reference point for all digital circuitry on the AD7328. The DGND and AGND
voltages should ideally be at the same potential and must not be more than 0.3 V apart, even on a
transient basis.
4
AGND
Analog Ground. Ground reference point for all analog circuitry on the AD7328. All analog input signals
and any external reference signal should be referred to this AGND voltage. The AGND and DGND voltages
should ideally be at the same potential and must not be more than 0.3 V apart, even on a transient basis.
5
REFIN/OUT Reference Input/Reference Output. The on-chip reference is available on this pin for use external to the
AD7328. The nominal internal reference voltage is 2.5 V, which appears at the pin. A 680 nF capacitor
should be placed on the reference pin. Alternatively, the internal reference can be disabled and an
external reference applied to this input. On power-up, the external reference mode is the default
condition (see the Reference section).
6
VSS
Negative Power Supply Voltage. This is the negative supply voltage for the analog input section.
7, 8, 14, 13, 9, 10,
12, 11
VIN0 to VIN7
Analog Input 0 to Analog Input 7. The analog inputs are multiplexed into the on-chip track-and-hold.
The analog input channel for conversion is selected by programming the Channel Address Bit ADD2
through Bit ADD0 in the control register. The inputs can be configured as eight single-ended inputs,
four true differential input pairs, four pseudo differential inputs, or seven pseudo differential inputs.
The configuration of the analog inputs is selected by programming the mode bits, Bit Mode 1 and
Bit Mode 0, in the control register. The input range on each input channel is controlled by program-
ming the range registers. Input ranges of ±10 V, ±5 V, ±2.5 V, and 0 V to +10 V can be selected on each
analog input channel when a +2.5 V reference voltage is used (see the Reference section).
15
VDD
Positive Power Supply Voltage. This is the positive supply voltage for the analog input section.
16
VCC
Analog Supply Voltage, 2.7 V to 5.25 V. This is the supply voltage for the ADC core on the AD7328.
This supply should be decoupled to AGND. Specifications apply from VCC = 4.75 V to 5.25 V.
17
VDRIVE
Logic Power Supply Input. The voltage supplied at this pin determines at what voltage the interface
operates. This pin should be decoupled to DGND. The voltage at this pin may be different to that at VCC,
but it should not exceed VCC by more than 0.3 V.
18
DOUT
Serial Data Output. The conversion output data is supplied to this pin as a serial data stream. The bits
are clocked out on the falling edge of the SCLK input, and 16 SCLKs are required to access the data. The
data stream consists of three channel identification bits, the sign bit, and 12 bits of conversion data.
The data is provided MSB first (see the Serial Interface section).
20
SCLK
Serial Clock, Logic Input. A serial clock input provides the SCLK used for accessing the data from the
AD7328. This clock is also used as the clock source for the conversion process.
Rev. A | Page 8 of 36
Share Link: 