M
Features
•
•
•
•
•
10-bit resolution
±1 LSB DNL, ±1 LSB INL max.
250 µA max conversion current
5 nA typical standby current, 1 µA max.
I
2
C™ compatible serial interface
- 100 kHz I
2
C Standard mode
- 400 kHz I
2
C Fast mode
Up to 8 devices on single 2-wire bus
22.3 ksps in I
2
C Fast mode
Single-ended analog input channel
On-chip sample and hold
On-chip conversion clock
Single supply specified operation: 2.7V to 5.5V
Temperature range:
- Extended: -40°C to +125°C
Small SOT-23 package
MCP3021
Description
The Microchip Technology Inc. MCP3021 is a succes-
sive approximation A/D converter (ADC) with 10-bit
resolution. Available in the SOT-23 package, this
device provides one single-ended input with very low
power consumption. Based on an advanced CMOS
technology, the MCP3021 provides a low maximum
conversion current and standby current of 250 µA and
1 µA, respectively. Low current consumption, com-
bined with the small SOT-23 package, make this
device ideal for battery-powered and remote data
acquisition applications.
Communication to the MCP3021 is performed using a
2-wire I
2
C compatible interface. Standard (100 kHz)
and Fast (400 kHz) I
2
C modes are available with the
device. An on-chip conversion clock enables indepen-
dent timing for the I
2
C and conversion clocks. The
device is also addressable, allowing up to eight devices
on a single 2-wire bus.
The MCP3021 runs on a single supply voltage that
operates over a broad range of 2.7V to 5.5V. This
device also provides excellent linearity of ±1 LSB differ-
ential non-linearity (DNL) and ±1 LSB integral non-
linearity (INL), maximum.
Low Power 10-Bit A/D Converter With I
2
C™ Interface
•
•
•
•
•
•
•
•
Applications
•
•
•
•
•
Data Logging
Multi-zone Monitoring
Hand Held Portable Applications
Battery Powered Test Equipment
Remote or Isolated Data Acquisition
Functional Block Diagram
V
DD
V
SS
Package Type
5-Pin SOT-23A
V
DD
1
V
SS
2
5
SCL
Sample
and
Hold
Clock
Control Logic
AIN 3
4
SDA
I
2
C™
Interface
SCL
SDA
DAC
Comparator
10-Bit SAR
–
+
AIN
2003 Microchip Technology Inc.
MCP3021
DS21805A-page 1
MCP3021
1.0
ELECTRICAL
CHARACTERISTICS
PIN FUNCTION TABLE
Name
V
DD
V
SS
AIN
SDA
SCL
Ground
Analog Input
Serial Data In/Out
Serial Clock In
Function
+2.7V to 5.5V Power Supply
Absolute Maximum Ratings †
V
DD
...................................................................................7.0V
Analog input pin w.r.t. V
SS
.......... ............. -0.6V to V
DD
+0.6V
SDA and SCL pins w.r.t. V
SS
........... .........-0.6V to V
DD
+1.0V
Storage temperature .....................................-65°C to +150°C
Ambient temp. with power applied ................-65°C to +125°C
Maximum Junction Temperature .......... .........................150°C
ESD protection on all pins (HBM) ......... ........................≥ 4 kV
†
Stresses above those listed under “Maximum ratings” may
cause permanent damage to the device. This is a stress rating
only and functional operation of the device at those or any
other conditions above those indicated in the operational list-
ings of this specification is not implied. Exposure to maximum
rating conditions for extended periods may affect device reli-
ability.
DC ELECTRICAL SPECIFICATIONS
Electrical Characteristics:
Unless otherwise noted, all parameters apply at V
DD
= 5.0V, V
SS
= GND, R
PU
= 2 kΩ
T
A
= -40°C to +85°C, I
2
C Fast Mode Timing: f
SCL
= 400 kHz (Note
3).
Parameters
DC Accuracy
Resolution
Integral Nonlinearity
Differential Nonlinearity
Offset Error
Gain Error
Dynamic Performance
Total Harmonic Distortion
Signal to Noise and Distortion
Spurious Free Dynamic Range
Analog Input
Input Voltage Range
Leakage Current
SDA/SCL (open-drain output)
Data Coding Format
High-level input voltage
Low-level input voltage
Low-level output voltage
Hysteresis of Schmitt trigger inputs
Note 1:
2:
3:
4:
5:
V
IH
V
IL
V
OL
V
HYST
—
—
—
Straight Binary
0.7 V
DD
—
—
—
0.05V
DD
—
0.3 V
DD
0.4
—
V
V
V
V
I
OL
= 3 mA, R
PU
= 1.53 kΩ
f
SCL
= 400 kHz only
V
SS
-0.3
-1
—
—
V
DD
+0.3
+1
V
µA
2.7V
≤
V
DD
≤
5.5V
THD
SINAD
SFDR
—
—
—
-70
60
74
—
—
—
dB
dB
dB
V
IN
= 0.1V to 4.9V @ 1 kHz
V
IN
= 0.1V to 4.9V @ 1 kHz
V
IN
= 0.1V to 4.9V @ 1 kHz
INL
DNL
—
—
—
—
10
±0.25
±0.25
±0.75
-1
±1
±1
±3
±3
bits
LSB
LSB
LSB
LSB
No missing codes
Sym
Min
Typ
Max
Units
Conditions
Sample time is the time between conversions after the address byte has been sent to the converter. Refer
to Figure 5-6.
This parameter is periodically sampled and not 100% tested.
R
PU
= Pull-up resistor on SDA and SCL.
SDA and SCL = V
SS
to V
DD
at 400 kHz.
t
ACQ
and t
CONV
are dependent on internal oscillator timing. See Figure 5-5 and Figure 5-6 for relation to
SCL.
DS21805A-page 2
2003 Microchip Technology Inc.
MCP3021
DC ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics:
Unless otherwise noted, all parameters apply at V
DD
= 5.0V, V
SS
= GND, R
PU
= 2 kΩ
T
A
= -40°C to +85°C, I
2
C Fast Mode Timing: f
SCL
= 400 kHz (Note
3).
Parameters
Input leakage current
Output leakage current
Pin capacitance
(all inputs/outputs)
Bus Capacitance
Power Requirements
Operating Voltage
Conversion Current
Standby Current
Active bus current
Conversion Rate
Conversion Time
Analog Input Acquisition Time
Sample Rate
Note 1:
2:
3:
4:
5:
t
CONV
t
ACQ
f
SAMP
—
—
—
8.96
1.12
—
—
—
22.3
µs
µs
ksps
Note 5
Note 5
f
SCL
= 400 kHz (Note
1)
V
DD
I
DD
I
DDS
I
DDA
2.7
—
—
—
—
175
0.005
—
5.5
250
1
120
V
µA
µA
µA
SDA, SCL = V
DD
Note 4
Sym
I
LI
I
LO
C
IN
,
C
OUT
C
B
Min
-1
-1
—
—
Typ
—
—
—
—
Max
+1
+1
10
400
Units
µA
µA
pF
pF
Conditions
V
IN
= V
SS
to V
DD
V
OUT
= V
SS
to V
DD
T
AMB
= 25°C, f = 1 MHz;
(Note
2)
SDA drive low, 0.4V
Sample time is the time between conversions after the address byte has been sent to the converter. Refer
to Figure 5-6.
This parameter is periodically sampled and not 100% tested.
R
PU
= Pull-up resistor on SDA and SCL.
SDA and SCL = V
SS
to V
DD
at 400 kHz.
t
ACQ
and t
CONV
are dependent on internal oscillator timing. See Figure 5-5 and Figure 5-6 for relation to
SCL.
TEMPERATURE SPECIFICATIONS
Electrical Characteristics:
All parameters apply across the operating voltage range.
Parameters
Temperature Ranges
Extended Temperature Range
Operating Temperature Range
Storage Temperature Range
Thermal Package Resistances
Thermal Resistance, 5L-SOT23A
θ
JA
—
256
—
°C/W
T
A
T
A
T
A
-40
-40
-65
—
—
—
+125
+125
+150
°C
°C
°C
Symbol
Min
Typ
Max
Units
Conditions
2003 Microchip Technology Inc.
DS21805A-page 3
MCP3021
TIMING SPECIFICATIONS
Electrical Characteristics:
All parameters apply at V
DD
= 2.7V - 5.5V, V
SS
= GND, T
A
= -40°C to +85°C.
Parameters
I
2
C Standard Mode
Clock frequency
Clock high time
Clock low time
SDA and SCL rise time
SDA and SCL fall time
START condition hold time
START condition setup time
Data input setup time
STOP condition setup time
STOP condition hold time
Output valid from clock
Bus free time
Input filter spike suppression
I
2
C Fast Mode
Clock frequency
Clock high time
Clock low time
SDA and SCL rise time
SDA and SCL fall time
START condition hold time
START condition setup time
Data input hold time
Data input setup time
STOP condition setup time
STOP condition hold time
Output valid from clock
Bus free time
Input filter spike suppression
Note 1:
2:
F
SCL
T
HIGH
T
LOW
T
R
T
F
T
HD:STA
T
SU:STA
T
HD:DAT
T
SU:DAT
T
SU:STO
T
HD:STD
T
AA
T
BUF
T
SP
0
600
1300
20 + 0.1C
B
20 + 0.1C
B
600
600
0
100
600
600
—
1300
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
400
—
—
300
300
—
—
0.9
—
—
—
900
—
50
kHz
ns
ns
ns
ns
ns
ns
ms
ns
ns
ns
ns
ns
ns
Note 2
SDA and SCL pins
(Note 1)
From V
IL
to V
IH
(Note 1)
From V
IL
to V
IH
(Note 1)
f
SCL
T
HIGH
T
LOW
T
R
T
F
T
HD:STA
T
SU:STA
T
SU:DAT
T
SU:STO
T
HD:STD
T
AA
T
BUF
T
SP
0
4000
4700
—
—
4000
4700
250
4000
4000
—
4700
—
—
—
—
—
—
—
—
—
—
—
—
—
—
100
—
—
1000
300
—
—
—
—
—
3500
—
50
kHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Note 2
SDA and SCL pins
(Note 1)
From V
IL
to V
IH
(Note
1)
From V
IL
to V
IH
(Note
1)
Sym
Min
Typ
Max
Units
Conditions
This parameter is periodically sampled and not 100% tested.
Time the bus must be free before a new transmission can start.
T
F
T
HIGH
V
HYS
T
R
SCL
T
SU:STA
T
LOW
T
HD:DAT
T
SU:DAT
T
SU:STO
T
HD:STA
T
AA
T
BUF
SDA
IN
T
SP
SDA
OUT
FIGURE 1-1:
Standard and Fast Mode Bus Timing Data.
DS21805A-page 4
2003 Microchip Technology Inc.
MCP3021
2.0
Note:
TYPICAL PERFORMANCE CURVES
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
Note:
Unless otherwise indicated, V
DD
= 5V, V
SS
= 0V, I
2
C Fast Mode Timing (SCL = 400 kHz), Continuous Conversion
Mode (f
SAMP
= 22.3 ksps), T
A
= +25°C.
0.25
1
0.20
0.8
0.15
0.6
0.10
0.4
INL (LSB)
0.005
0.2
0
-0.005
-0.2
-0.10
-0.4
-0.15
-0.6
-0.20
-0.8
-0.25
-1
0
100
200
I C Bus Rate (kHz)
2
1
0.25
0.20
0.8
Positive INL
INL (LSB)
0.15
0.6
0.10
0.4
0.005
0.2
0
Positive INL
-0.005
-0.2
-0.10
-0.4
-0.15
-0.6
-0.20
-0.8
-0.25
-1
0
100
2
Negative INL
Negative INL
300
400
200
I C Bus Rate (kHz)
300
400
FIGURE 2-1:
INL vs. Clock Rate.
FIGURE 2-4:
(V
DD
= 2.7V).
0.25
1
INL vs. Clock Rate
0.25
1
0.20
0.8
0.15
0.6
0.10
0.4
INL (LSB)
INL (LSB)
Positive INL
0.20
0.8
0.15
0.6
0.10
0.4
0.005
0.2
0
-0.005
-0.2
-0.10
-0.4
-0.15
-0.6
-0.20
-0.8
-0.25
-1
Negative INL
Positive INL
0.005
0.2
0
-0.005
-0.2
-0.10
-0.4
-0.15
-0.6
-0.20
-0.8
-0.25
-1
2.5
3
3.5
4
V
DD
(V)
4.5
5
5.5
Negative INL
2.5
3
3.5
4
V
DD
(V)
4.5
5
5.5
FIGURE 2-2:
INL vs. V
DD
- I
2
C Standard
Mode (f
SCL
= 100 kHz).
0.5
0.4
0.3
0.2
INL (LSB)
0
-0.1
-0.2
-0.3
-0.4
-0.5
0
256
512
Digital Code
768
1024
0.1
FIGURE 2-5:
(f
SCL
= 400 kHz).
0.5
0.4
0.3
0.2
INL (LSB)
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.5
0
256
INL vs. V
DD
- I
2
C Fast Mode
512
Digital Code
768
1024
FIGURE 2-3:
INL vs. Code
(Representative Part).
FIGURE 2-6:
INL vs. Code
(Representative Part, V
DD
= 2.7V).
2003 Microchip Technology Inc.
DS21805A-page 5
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