Document Outline
- WM2148
- 14-bit 8MSPS Analogue-To-Digital Converter
- Production Data, February 2001, Rev 1.1
- DESCRIPTION
- FEATURES
- APPLICATIONS
- BLOCK DIAGRAM
- PIN CONFIGURATION
- ORDERING INFORMATION
- PIN DESCRIPTION
- ABSOLUTE MAXIMUM RATINGS
- RECOMMENDED OPERATING CONDITIONS
- ELECTRICAL CHARACTERISTICS
- DEVICE DESCRIPTION
- INTRODUCTION
- CONTROL INTERFACE
- PERFORMANCE DATA (TYPICAL)
- APPLICATION INFORMATION
- DRIVING THE ANALOGUE INPUT
- DIGITAL I/O
- RECOMMENDED EXTERNAL COMPONENTS
- PACKAGE DIMENSIONS
WM2148
14-bit 8MSPS Analogue-To-Digital Converter
Production Data, February 2001, Rev 1.1
WOLFSON MICROELECTRONICS LTD
Bernard Terrace, Edinburgh, EH8 9NX, UK
Tel: +44 (0) 131 667 9386
Fax: +44 (0) 131 667 5176
Email: sales@wolfson.co.uk
http://www.wolfson.co.uk
Production Data datasheets contain final
specifications current on publication date.
Supply of products conforms to Wolfson
Microelectronics' Terms and Conditions.
2001 Wolfson Microelectronics Ltd
.
DESCRIPTION
The WM2148 is a 14-bit, 8 MSPS analogue to digital
converter with an on-chip voltage reference, high bandwidth
sample and hold amplifier and programmable gain. The
analogue input is differential, giving excellent common-
mode noise immunity and low distortion.
The WM2148 is designed for use in highly integrated, low-
power 3.3V systems. A high speed, microprocessor
compatible parallel interface allows control of the ADC input
gain, digital DC offset, internal / external reference and
output data format. Both binary and two's complement
formats are supported. The device also features an out of
range indicator pin to show when the input signal exceeds
the converter's full-scale range.
In Power Down mode, all analogue circuitry is internally
disconnected from the power supply, reducing total supply
current to 20
A.
The WM2148 is available in a 1mm thin 48-pin TQFP
package in standard commercial and industrial temperature
ranges.
FEATURES
14-bit resolution ADC
8 MSPS conversion rate
Differential
input
3.3V single supply
Very low current power down mode - 20
A typical
Microprocessor compatible parallel interface
Internal or external voltage reference
High bandwidth sample and hold amplifier
-
140MHz full-power bandwidth
Programmable Gain Amplifier (PGA)
Programmable DC offset
Binary or two's complement output format
Out of range indicator
48-pin TQFP package, body thickness 1mm
APPLICATIONS
Communications
xDSL Front ends
Industrial
control
Instrumentation
BLOCK DIAGRAM
IN+
PARALLEL INTERFACE AND
CONTROL LOGIC
A[1:0]
CSB
WEB
OEB
ADC
+
PGA
-
IN-
D[13:0]
OUTPUT
BUFFERS
REF+
REF-
OVI
CLK
VBG
WM2148
PRECISION
REFERENCE
WM2148
Production Data
WOLFSON MICROELECTRONICS LTD
PD Rev 1.1 February 2001
2
PIN CONFIGURATION
ORDERING INFORMATION
DEVICE
TEMP. RANGE
PACKAGE
WM2148CFT/V
0 to +70
o
C
WM2148IFT/V
-40 to +85
o
C
48-pin TQFP
1 mm thick body
IN-
C
S
B
D
V
D
D
C
T
R
L
A
0
A
1
N
C
N
C
I
N
+
A
V
D
D
2
A
V
S
U
B
A
G
N
D
1
A
V
D
D
1
D1
1
D7
DGND
OP1
D8
D9
D10
DVDD
OP1
D5
D3
D4
D6
DVDD
OP3
WRB
DVDDLOGIC
CLK
DGNDCLK
DGNDCTRL
OEB
DGNDOP2
DVDDOP2
D2
D1
1
9
8
7
6
5
4
3
2
12
11
10
14
21
20
19
18
17
16
15
24
23
22
13
25
31
30
29
28
27
26
36
35
34
33
32
48
38
39
40
41
42
43
44
45
46
47
37
D0
DVDDCLK
A
G
N
D
2
AVDDREF
VBG
CML
REF+
REF-
AGNDREF
VSUB
DGNDLOGIC
OVI
D13
D12
PIN DESCRIPTION
PIN
NAME
TYPE
DESCRIPTION
1
IN-
Analogue Input
Negative Differential Analogue Input
2
AVDDREF
Supply
Positive Supply Voltage for Reference
3
VBG
Analogue I/O
Bandgap Voltage / External Reference
4
CML
Analogue Output
Reference Decoupling Point
5
REF+
Analogue Output
Positive Reference Voltage
6
REF-
Analogue Output
Negative Reference Voltage
7
AGNDREF
Supply
Reference Block Ground
8
VSUB
Supply
Device Substrate
9
DGNDLOGIC
Supply
Digital Ground for Logic Block
10
OVI
Digital Output
Out of Range Indicator
11
D13
Digital I/O
Data Bit 13
12
D12
Digital I/O
Data Bit 12
13
D11
Digital I/O
Data Bit 11
14
DVDDOP1
Supply
Positive Supply for Output Drivers
15
DGNDOP1
Supply
Ground for Output Drivers
16
D10
Digital I/O
Data Bit 10
17
D9
Digital I/O
Data Bit 9
18
D8
Digital I/O
Data Bit 8
19
D7
Digital I/O
Data Bit 7
20
DVDDOP3
Supply
Positive Supply for Output Drivers
21
D6
Digital I/O
Data Bit 6
22
D5
Digital I/O
Data Bit 5
23
D4
Digital I/O
Data Bit 4
24
D3
Digital I/O
Data Bit 3
25
DGNDOP2
Supply
Ground for Output Drivers
26
DVDDOP2
Supply
Positive Supply for Output Drivers
Production Data
WM2148
WOLFSON MICROELECTRONICS LTD
PD Rev 1.1 February 2001
3
PIN
NAME
TYPE
DESCRIPTION
27
D2
Digital I/O
Data Bit 2
28
D1
Digital I/O
Data Bit 1
29
D0
Digital I/O
Data Bit 0
30
DVDDLOGIC
Supply
Positive Supply Voltage for Logic Block
31
DVDDCLK
Supply
Positive Supply Voltage for Clock
32
CLK
Digital Input
Sample Clock
33
DGNDCLK
Supply
Ground for Clock
34
DGNDCTRL
Supply
Ground for Control Pins
35
OEB
Digital Input
Output Enable (active low)
36
WRB
Digital Input
Write Signal (active low)
37
CSB
Digital Input
Chip Select (active low)
38
NC
Test Output
This pin must be left unconnected
39
NC
Test Output
This pin must be left unconnected
40
A1
Digital Input
Address Bit 1
41
A0
Digital Input
Address Bit 0
42
DVDDCTRL
Supply
Positive Supply for Control Pins
43
AVDD1
Supply
Positive Supply for ADC
44
AGND1
Supply
Ground for ADC
45
AVSUB
Substrate
ADC substrate
46
AGND2
Supply
Positive Supply for ADC Op-amps
47
AVDD2
Supply
Ground for ADC Op-amps
48
IN+
Analogue Input
Positive Differential Analogue Input
Note:
1.
It is recommended that each pair of supply pins, especially the analogue supplies, have a separate decoupling
capacitor. The most critical are pins 46 and 47. The ADC substrate (pin 45) should be as noise free as possible.
WM2148
Production Data
WOLFSON MICROELECTRONICS LTD
PD Rev 1.1 February 2001
4
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are stress ratings only. Permanent damage to the device may be caused by continuously operating at
or beyond these limits. Device functional operating limits and guaranteed performance specifications are given under Electrical
Characteristics at the test conditions specified.
ESD Sensitive Device. This device is manufactured on a CMOS process. It is therefore generically susceptible
to damage from excessive static voltages. Proper ESD precautions must be taken during handling and storage
of this device.
As per JEDEC specifications A112 and A113, this product requires specific storage conditions prior to surface mount assembly. It
has been classified as having a Moisture Sensitivity Level of 2 and as such will be supplied in vacuum-sealed moisture barrier
bags.
CONDITION
MIN
MAX
Analogue Supply Voltage (AV
DD
to AGND)
-0.3
4 V
Digital Supply Voltage (DV
DD
to DGND)
-0.3
4 V
Reference Input Voltage Range (VBG)
AGND -0.3V
AV
DD
+0.3V
Analogue Inputs Voltage Range
AGND -0.3V
AV
DD
+0.3V
Digital Inputs Voltage Range
DGND -0.3V
DV
DD
+0.3V
C suffix
0
C
+70
C
Operating temperature range (T
A
)
I suffix
-40
C
+85
C
Storage temperature
-65
C
+150
C
Lead temperature (soldering 10 seconds, 1.6 mm from package body)
+260
C
RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Supply Voltages
(digital and analogue)
AV
DD
, DV
DD
3.0
3.3
3.6
V
Reference Input Voltage
V
BG
External reference
1.425
1.5
1.575
V
Digital Input HIGH Level
V
IH
2
3.3
V
Digital Input LOW Level
V
IL
0
0.8
V
Load Capacitance
C
L
5
15
pF
Clock Frequency
f
CLK
0.1
8
8
MHz
Clock Duty Cycle
40
50
60
%
C Suffix
0
25
70
Operating Free-air Temperature
T
A
I Suffix
-40
25
85
C
Production Data
WM2148
WOLFSON MICROELECTRONICS LTD
PD Rev 1.1 February 2001
5
ELECTRICAL CHARACTERISTICS
Electrical characteristics over recommended temperature range, AV
DD
= DV
DD
= 3.3V (unless otherwise noted)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Power Supplies
Analogue Supply Current
AI
DD
AV
DD
= 3.6V
81
90
mA
Digital Supply Current
DI
DD
DV
DD
= 3.6V
5
10
mA
Power Consumption
P
AV
DD
= DV
DD
= 3.6V
270
360
mW
Power Down Supply Current
(sum of all supply currents)
I
PD
=
AI
DD
+DI
DD
Power down mode
CLK signal stopped
20
A
DC Characteristics
Resolution
14
bits
Differential Nonlinearity
DNL
0.6
1
bits
Integral Nonlinearity
INL
Best Fit
3
5
bits
Offset Error
IN+ = IN-, 0dB gain
0.3
% of FSR
Gain Error
0 dB gain
1
% of FSR
AC Characteristics
Analogue Input Bandwidth
140
MHz
F
IN
= 100kHz
-81
F
IN
= 1MHz
-78
Total Harmonic Distortion
THD
F
IN
= 4MHz
-77
dB
F
IN
= 1MHz
70
72
Signal to Noise Ratio
SNR
F
IN
= 4MHz
71
dB
F
IN
= 1MHz
69
70
Signal to Noise plus Distortion
SINAD
F
IN
= 4MHz
70
dB
F
IN
= 1MHz
73
80
Spurious Free Dynamic Range
SFDR
F
IN
= 4MHz
80
dB
Effective Number of Bits
ENOB
11.2
11.5
bits
Reference Voltage
Bandgap Voltage
V
BG
Internal reference
1.425
1.5
1.575
V
Temperature Coefficient
40
ppm / C
Supply Voltage Coefficient
200
ppm / V
V
BG
Input Impedance
External reference
40
k
Positive Reference Voltage
V
REF+
V
REF+
= V
BG
(1 +
2
/
3
)
2.5
V
Negative Reference Voltage
V
REF
V
REF+
= V
BG
(1 -
2
/
3
)
0.5
V
Reference Voltage Difference
9
REF
9
REF
= V
REF+
-
V
REF
2.0
V
Analog Inputs
Positive Analogue Input Voltage
V
IN+
0
AV
DD
V
Negative Analogue Input Voltage
V
IN
0
AV
DD
V
Input Voltage Difference
9
IN
9
IN
= V
IN+
- V
IN
-
9
REF
9
REF
V
Input impedance
Z
IN
25
k
PGA Range
0
7
dB
PGA Step Size
1
dB
PGA Gain Error
0.25
dB
Digital Inputs
Input LOW level
V
IL
0.8
V
Input HIGH level
V
IH
2
V
Input current
I
IN
1
A
Input capacitance
C
IN
5
pF
PDF 
ZIP