AD7898 Analog Devices, AD7898 Datasheet - Page 16

• Manufacturer Part Number: AD7898
• Description: 5V, 12-Bit, Serial 220 kSPS ADC in a 8-Lead Package
• Manufacturer: Analog Devices

Specifications of AD7898

• Resolution (bits): 12bit
• # Chan: 1
• Sample Rate: 220kSPS
• Interface: Ser
• Analog Input Type: SE-Bip
• Ain Range: Bip (Vref),Bip (Vref) x 4,Bip 10V,Bip 2.5V
• Adc Architecture: SAR
• Pkg Type: SOIC

AD7898
AD7898 to MC68HC16 Interface
The Serial Peripheral Interface (SPI) on the MC68HC16 is
configured for Master Mode (MSTR = 1), Clock Polarity Bit
(CPOL) = 1 and the Clock Phase Bit (CPHA) = 0. The SPI is
configured by writing to the SPI Control Register (SPCR) (see
68HC16 user manual). The serial transfer will take place as a
16-bit operation when the SIZE bit in the SPCR register is set
to SIZE = 1. To implement the power-down modes with an
8-bit transfer set SIZE = 0. A connection diagram is shown in
Figure 20. The V
ply voltage as that of the MC68HC16. This allows the ADC
to operate at a higher voltage than the serial interface, i.e.,
MC68HC16, if necessary.
Revision History
Location
3/04—Data Sheet changed from REV. 0 to REV. A.
Added Patent Note . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Changes to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Updated OUTLINE DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
DRIVE
pin of the AD7898 takes the same sup-
0.25 (0.0098)
0.10 (0.0040)
COPLANARITY
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
4.00 (0.1574)
3.80 (0.1497)
8-Lead Standard Small Outline Package [SOIC]
0.10
Dimensions shown in millimeters and (inches)
COMPLIANT TO JEDEC STANDARDS MS-012AA
SEATING
5.00 (0.1968)
4.80 (0.1890)
1.27 (0.0500)
PLANE
8
1
OUTLINE DIMENSIONS
BSC
5
4
0.51 (0.0201)
0.31 (0.0122)
Narrow Body
6.20 (0.2440)
5.80 (0.2284)
1.75 (0.0688)
1.35 (0.0532)
(R-8)
–16–
0.25 (0.0098)
0.17 (0.0067)
*ADDITIONAL PINS OMITTED FOR CLARITY
Figure 20. AD7898 to MC68HC16 Interface
AD7898*
8
0
0.50 (0.0196)
0.25 (0.0099)
1.27 (0.0500)
0.40 (0.0157)
SDATA
V
SCLK
DRIVE
CS
45
SCLK/PMC2
MISO/PMC0
SS/PMC3
MC68HC16*
V
DD
REV. A
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