ON NCS7101 1.8 volt rail-to-rail operational amplifier Datasheet

NCS7101, NCV7101
1.8 Volt Rail-to-Rail
Operational Amplifier
The NCS7101 operational amplifier provides rail−to−rail operation
on both the input and output. The output can swing within 50 mV of
each rail. This rail−to−rail operation enables the user to make full use
of the entire supply voltage range available. It is designed to work at
very low supply voltages (1.8 V and ground), yet can operate with a
supply of up to 10 V and ground. The NCS7101 is available in the
space saving SOT−23−5 package with two industry standard pinouts.
Features
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LOW VOLTAGE
RAIL−TO−RAIL
OPERATIONAL AMPLIFIER
• Low Voltage, Single Supply Operation (1.8 V and Ground to 10 V
•
•
•
•
•
•
•
•
•
•
•
and Ground)
1.0 pA Input Bias Current
Unity Gain Bandwidth of 1.0 MHz at 5.0 V,
0.9 MHz at 1.8 V
Output Voltage Swings Within 50 mV of Both Rails @ 1.8 V
No Phase Reversal on the Output for Over−Driven Input Signals
Input Offset Trimmed to 1.0 mV
Low Supply Current (ID = 1.0 mA)
Works Down to Two Discharged NiCd Battery Cells
ESD Protected Inputs Up to 2.0 kV
These Devices are Pb−Free and are RoHS Compliant
AEC−Q100 Qualified and PPAP Capable
*NCV Prefix for Automotive and Other Applications Requiring
Unique Site and Control Change Requirements
Typical Applications
•
•
•
•
•
Dual NiCd/NiMH Cell Powered Systems
Portable Communication Devices
Low Voltage Active Filters
Power Supply Monitor and Control
Interface to DSP
CASE 483
SOT−23−5
SN SUFFIX
5
1
MARKING DIAGRAM
x = C for SN1
D for SN2
AAx AYWG
A = Assembly Location
G
Y = Year
W = Work Week
1
G = Pb−Free Package
(Note: Microdot may be in either location)
5
PIN CONNECTIONS
VOUT
1
VCC
Non−Inverting
Input
2
3
+ −
5
VEE
4
Inverting
Input
Style 1 Pin Out (SN1T1)
VOUT
1
VEE
Non−Inverting
Input
2
3
+ −
5
VCC
4
Inverting
Input
Style 2 Pin Out (SN2T1)
Rail to Rail Input
Rail to Rail Output
ORDERING INFORMATION
Device
1.8 V
to
10 V
NCV7101SN1T1G*
NCS7101SN2T1G
SOT−23−5 3000 Tape & Reel
(7 inch Reel)
(Pb−Free)
NCV7101SN2T1G*
This device contains 68 active transistors.
Figure 1. Typical Application
October, 2011 − Rev. 4
Shipping†
NCS7101SN1T1G
+
-
© Semiconductor Components Industries, LLC, 2011
Package
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specifications
Brochure, BRD8011/D.
1
Publication Order Number:
NCS7101/D
NCS7101, NCV7101
MAXIMUM RATINGS
Rating
Symbol
Value
Unit
VS
10
V
Input Differential Voltage Range (Note 1)
VIDR
VEE − 300 mV to 10 V
V
Input Common Mode Voltage Range (Note 1)
VICR
VEE − 300 mV to 10 V
V
Output Short Circuit Duration (Note 2)
tSC
Indefinite
sec
Junction Temperature
TJ
150
°C
Power Dissipation and Thermal Characteristics − SOT−23−5 Package
Thermal Resistance, Junction−to−Air
Power Dissipation @ TA = 70°C
RqJA
PD
220
364
°C/W
mW
Storage Temperature Range
Tstg
−65 to +150
°C
TA
−40 to +85
−40 to +125
°C
VESD
2000
V
Supply Voltage (VCC to VEE)
Operating Ambient Temperature Range
NCS7101
NCV7101
ESD Protection at any Pin Human Body Model (Note 3)
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
1. Either or both inputs should not exceed the range of VEE − 300 mV to VEE + 10 V.
2. Maximum package power dissipation limits must be observed to ensure that the maximum junction temperature is not exceeded.
TJ = TA + (PDRqJA)
3. ESD data available upon request.
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2
NCS7101, NCV7101
DC ELECTRICAL CHARACTERISTICS
(VCC = 2.5 V, VEE = −2.5 V, VCM = VO = 0, RL to GND, TA = 25°C, unless otherwise noted.)
Characteristics
Symbol
Input Offset Voltage
VCC = 0.9 V, VEE = −0.9 V
TA = 25°C
TA = TLow to THigh
VCC = 2.5 V, VEE = −2.5 V
TA = 25°C
TA = TLow to THigh
VCC = 5.0 V, VEE = −5.0 V
TA = 25°C
TA = TLow to THigh
Min
Typ
Max
VIO
Unit
mV
−7.0
−9.0
0.6
−
7.0
9.0
−7.0
−9.0
0.6
−
7.0
9.0
−7.0
−9.0
0.6
−
7.0
9.0
DVIO/DT
−
8.0
−
mV/°C
|IIB|
−
1.0
−
pA
Common Mode Input Voltage Range
VICR
VEE
−
VCC
Large Signal Voltage Gain
VCC = 5.0 V, VEE = −5.0 V
RL = 10 kW
RL = 2.0 kW
AVOL
Output Voltage Swing, High (VID = "0.2 V)
VCC = 0.9 V, VEE = −0.9 V (TA = 25°C)
RL = 10 k
RL = 2.0 k
TA = TLow to THigh
RL = 10 k
RL = 2.0 k
VCC = 2.5 V, VEE = −2.5 V (TA = 25°C)
RL = 600
RL = 2.0 k
TA = TLow to THigh
RL = 600
RL = 2.0 k
VCC = 5.0 V, VEE = −5.0 V (TA = 25°C)
RL = 600
RL = 2.0 k
TA = TLow to THigh
RL = 600
RL = 2.0 k
VOH
Output Voltage Swing, Low (VID = "0.2 V)
VCC = 0.9 V, VEE = −0.9 V (TA = 25°C)
RL = 10 k
RL = 2.0 k
TA = TLow to THigh
RL = 10 k
RL = 2.0 k
VCC = 2.5 V, VEE = −2.5 V (TA = 25°C)
RL = 600
RL = 2.0 k
TA = TLow to THigh
RL = 600
RL = 2.0 k
VCC = 5.0 V, VEE = −5.0 V (TA = 25°C)
RL = 600
RL = 2.0 k
TA = TLow to THigh
RL = 600
RL = 2.0 k
VOL
Input Offset Voltage Temperature Coefficient (RS = 50)
TA = −40°C to 125°C
Input Bias Current (VCC = 1.8 V to 10 V)
16
16
Common Mode Rejection Ratio
Vin = 0 to 10 V
Vin = 0 to 5.0 V
50
30
−
−
V
0.85
0.80
0.88
0.82
−
−
0.85
0.79
−
−
−
−
2.10
2.35
2.21
2.44
−
−
2.00
2.40
−
−
−
−
4.40
4.80
4.60
4.88
−
−
4.40
4.80
−
−
−
−
V
−
−
−0.88
−0.82
−0.85
−0.80
−
−
−
−
−0.85
−0.78
−
−
−2.22
−2.38
−2.10
−2.35
−
−
−
−
−2.00
−2.30
−
−
−4.66
−4.88
−4.40
−4.80
−
−
−
−
−4.35
−4.80
65
60
−
−
−
−
CMRR
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3
V
kV/V
dB
NCS7101, NCV7101
DC ELECTRICAL CHARACTERISTICS (continued)
(VCC = 2.5 V, VEE = −2.5 V, VCM = VO = 0, RL to GND, TA = 25°C, unless otherwise noted.)
Characteristics
Power Supply Rejection Ratio
VCC/VEE = 10 V/Ground, DVS = 2.5 V
Symbol
Min
Typ
Max
Unit
PSRR
65
−
−
dB
Output Short Circuit Current (Vin Diff = "1.0 V)
VCC = +0.9 V, VEE = −0.9 V
Source
Sink
VCC = +2.5 V, VEE = −2.5 V
Source
Sink
VCC = 5.0 V, VEE = −5.0 V
Source
Sink
ISC
Power Supply Current (VO = 0 V)
VCC = +0.9 V, VEE = −0.9 V
TA = 25°C
TA = −40°C to 85°C
TA = −40°C to 125°C
VCC = +2.5 V, VEE = −2.5 V
TA = 25°C
TA = −40°C to 85°C
TA = −40°C to 125°C
VCC = 5.0 V, VEE = −5.0 V
TA = 25°C
TA = −40°C to 85°C
TA = −40°C to 125°C
ID
mA
−
−
3.0
−3.0
−
−
20
−60
25
−25
60
−20
50
−140
72
−72
140
−50
mA
−
−
−
0.97
−
−
1.20
1.30
1.60
−
−
−
1.05
−
−
1.30
1.40
1.70
−
−
−
1.13
−
−
1.40
1.50
1.80
Symbol
Min
Typ
Max
Unit
SR
0.7
1.2
3.0
V/ms
Gain Bandwidth Product (VCC = 10 V)
GBW
0.5
1.0
3.0
MHz
Gain Margin (RL = 10 k, CL = 5.0 pF)
Am
−
6.5
−
dB
Phase Margin (RL = 10 k, CL = 5.0 pF)
φm
−
60
−
Deg
Power Bandwidth (VO = 4.0 Vpp, RL = 2.0 kW, THD v 1.0%)
BWP
−
130
−
kHz
Total Harmonic Distortion (VO = 4.0 Vpp, RL = 2.0 kW, AV = 1.0)
f = 1.0 kHz
f = 10 kHz
THD
−
−
0.02
0.2
−
−
AC ELECTRICAL CHARACTERISTICS
(VCC = 2.5 V, VEE = −2.5 V, VCM = VO = 0, RL to GND, TA = 25°C, unless otherwise noted.)
Characteristics
Slew Rate (VO = −2.0 to 2.0 V, RL = 2.0 kW, AV = 1.0)
%
Differential Input Resistance (VCM = 0 V)
Rin
−
u1.0
−
tera W
Differential Input Capacitance (VCM = 0 V)
Cin
−
2.0
−
pF
Equivalent Input Noise Voltage (Freq = 1.0 kHz)
en
−
140
−
nV/√Hz
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4
0
Vsat, OUTPUT SATURATION VOLTAGE (V)
Vsat, OUTPUT SATURATION VOLTAGE (mV)
NCS7101, NCV7101
VCC
−400
High State Output
Sourcing Current
−800
−1200
−0.4
VS = ±2.5 V
RL = to GND
TA = 25°C
−1.2
Low State Output
Sinking Current
400
0
VEE
100
1.0 k
10 k
100 k
1.0 M
VCC
VS = ±2.5 V
RL = to GND
TA = 25°C
−0.8
1200
800
0
High State Output
Sourcing Current
Low State Output
Sinking Current
1.2
0.8
VEE
0.4
0
0
4.0
2.0
6.0
8.0
10
12
RL, LOAD RESISTANCE (W)
IL, LOAD CURRENT (mA)
Figure 2. Output Saturation Voltage versus
Load Resistance
Figure 3. Output Saturation Voltage versus
Load Current
1000
1.0
VS = ±2.5 V
RL = ∞
CL = 0
AV = 1.0
0.1
80
60
25
50
75
100
−20
−60
PHASE
40
−100
20
−140
0
125
1.0
10
100
1.0 k
10 k
100 k
1.0 M
−180
10 M
TA, AMBIENT TEMPERATURE (°C)
f, FREQUENCY (Hz)
Figure 4. Input Bias Current versus
Temperature
Figure 5. Gain and Phase versus Frequency
VS = ±2.5 V
VO = 4.0 VPP
RL = 10 k
CL = 10 pF
AV = 1.0
TA = 25°C
50 mV/div
0
0
f, EXCESS PHASE (°)
10
AVOL, GAIN (dB)
100
0
VS = ±5.0 V
RL = 100 k
TA = 25°C
GAIN
500 mV/div
IIB, INPUT CURRENT (pA)
100
VS = ±2.5 V
VO = 4.0 VPP
RL = 10 k
CL = 10 pF
AV = 1.0
TA = 25°C
t, time (500 ns/Div)
t, time (1.0 ms/Div)
Figure 6. Transient Response
Figure 7. Slew Rate
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NCS7101, NCV7101
VS = ±5.0 V
10
CMR, COMMON MODE REJECTION (dB)
12
8.0
6.0
VS = ±2.5 V
4.0
VS = ±0.9 V
2.0
0
PSR, POWER SUPPLY REJECTION (dB)
RL = 10 k
AV = 1.0
TA = 25°C
1.0 k
10 k
100 k
VS = ±2.5 V
RL = ∞
TA = 25°C
AV = 1.0
70
60
50
40
30
20
10
0
−10
10
10 k
100 k
10 M
1.0 M
Figure 9. Common Mode Rejection versus
Frequency
VS = ±2.5 V
RL = ∞
TA = 25°C
AV = 1.0
PSR+
70
60
50
PSR−
40
30
20
10
100
1.0 k
10 k
100 k
1.0 M
10 M
f, FREQUENCY (Hz)
140
Output Pulsed Test
at 3% Duty Cycle
120
100
−40°C
80
25°C
60
85°C
40
20
0
0
±1.0
±2.0
±3.0
±4.0
±5.0
VS, SUPPLY VOLTAGE (V)
Figure 11. Output Short Circuit Sinking
Current versus Supply Voltage
Figure 10. Power Supply Rejection versus
Frequency
140
1.4
Output Pulsed Test
at 3% Duty Cycle
120
|ID|, SUPPLY CURRENT (mA)
|ISC|, OUTPUT SHORT CIRCUIT CURRENT (mA)
1.0 k
Figure 8. Output Voltage versus Frequency
80
−40°C
100
25°C
80
60
85°C
40
20
0
100
f, FREQUENCY (Hz)
90
10
90
80
f, FREQUENCY (Hz)
100
0
−10
100
1.0 M
|ISC|, OUTPUT SHORT CIRCUIT CURRENT (mA)
Vout, OUTPUT VOLTAGE (VPP)
14
0
±1.0
±2.0
±3.0
±4.0
1.0
25°C
0.8
−40°C
0.6
0.4
RL = ∞
AV = 1.0
Vin = 0 V
0.2
0
±5.0
85°C
1.2
0
±1.0
±2.0
±3.0
±4.0
VS, SUPPLY VOLTAGE (V)
VS, SUPPLY VOLTAGE (V)
Figure 12. Output Short Circuit Sourcing
Current versus Supply Voltage
Figure 13. Supply Current versus Supply
Voltage with No Load
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±5.0
AV = 1000
1.0
AV = 100
AV = 10
0.01
0.001
VS = ±2.5 V
Vout = 4.0 VPP
RL = 2 k
TA = 25°C
AV = 1.0
10
100
1.0 k
10 k
100 k
AV = 10
VS = ±5.0 V
Vout = 8.0 VPP
RL = 2 k
TA = 25°C
0.01
AV = 1.0
0.001
10
100
1.0 k
10 k
100 k
Figure 15. Total Harmonic Distortion versus
Frequency with 10 V Supply
AV = 1000
0.1
AV = 100
VS = ±2.5 V
Vout = 4.0 VPP
RL = 10 k
TA = 25°C
AV = 10
0.01
AV = 1.0
10
100
1.0 k
10 k
100 k
10
1.0
AV = 1000
0.1
AV = 100
0.01
0.001
10
VS = ±5.0 V
Vout = 8.0 VPP
RL = 10 k
TA = 25°C
AV = 10
AV = 1.0
100
1.0 k
10 k
100 k
f, FREQUENCY (Hz)
f, FREQUENCY (Hz)
Figure 16. Total Harmonic Distortion versus
Frequency with 5.0 V Supply
Figure 17. Total Harmonic Distortion versus
Frequency with 10 V Supply
1.6
+Slew Rate, VS = ±2.5 V
SR, SLEW RATE (V/ms)
AV = 100
0.1
Figure 14. Total Harmonic Distortion versus
Frequency with 5.0 V Supply
1.0
1.2
−Slew Rate, VS = ±2.5 V
RL = 10 k
CL = 10 pF
AV = 1.0
TA = 25°C
0.8
0.4
+Slew Rate, VS = ±0.9 V
0
−50
AV = 1000
1.0
f, FREQUENCY (Hz)
10
0.001
10
f, FREQUENCY (Hz)
THD, TOTAL HARMONIC DISTORTION (%)
0.1
THD, TOTAL HARMONIC DISTORTION (%)
10
GBW, GAIN BANDWIDTH PRODUCT (MHz)
THD, TOTAL HARMONIC DISTORTION (%)
THD, TOTAL HARMONIC DISTORTION (%)
NCS7101, NCV7101
−Slew Rate, VS = ±0.9 V
−25
0
25
50
75
100
125
3.0
VS = ±2.5 V
RL = 10 k
CL = 5.3 pF
2.0
1.0
0
−50
−25
0
25
50
75
100
TA, AMBIENT TEMPERATURE (°C)
TA, AMBIENT TEMPERATURE (°C)
Figure 18. Slew Rate versus Temperature (Avg.)
Figure 19. Gain Bandwidth Product versus
Temperature
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125
NCS7101, NCV7101
−100
10
−140
0
−180
−220
VS = ±0.9 V
VS = ±2.5 V
−20
10 k
100 k
−260
1.0 M
10 M
100 M
80
40
40
Gain Margin
20
VS = ±2.5 V
RL = 10 k
CL = 5.0 pF
TA = 25°C
10
30
30
20
0
−50
−25
0
25
50
75
0
125
100
100
0
1.0 k
10 k
100 k
70
60
VS = ±2.5 V
RL = 10 k
AV = 100
TA = 25°C
Phase Margin
50
60
50
40
40
30
30
20
−20
10
−40
1.0M
0
20
Gain Margin
1.0
10
10
0
1000
100
CL, CAPACITIVE LOAD (pF)
Figure 22. Gain and Phase Margin versus
Differential Source Resistance
Figure 23. Gain and Phase Margin versus
Output Load Capacitance
80
12
Phase Margin
70
10
Am, GAIN MARGIN (dB)
Vout, OUTPUT VOLTAGE (VPP)
10
70
Rt, DIFFERENTIAL SOURCE RESISTANCE (W)
8.0
6.0
RL = 10 k
AV = 100
TA = 25°C
Split Supplies
4.0
2.0
0
20
Gain Margin
Figure 21. Gain and Phase Margin versus
Temperature
60
−40
40
Figure 20. Voltage Gain and Phase versus
Frequency
60
−20
40
50
TA, AMBIENT TEMPERATURE (°C)
Phase Margin
0
VS = ±2.5 V
RL = 10 k
CL = 10 pF
50
10
100
20
60
f, FREQUENCY (Hz)
100
80
70
60
−300
AV, GAIN MARGIN (dB)
−30
Φ, EXCESS PHASE (°)
20
−10
Am, GAIN MARGIN (dB)
−60
80
Phase Margin
70
Am, GAIN MARGIN (dB)
30
−20
Φm, PHASE MARGIN (°)
AV, GAIN (dB)
40
80
0
2.0
4.0
6.0
8.0
60
AV = 100
RL = 10 k
CL = 0
TA = 25°C
50
40
30
20
Gain Margin
10
0
10
0
±1.0
±2.0
±3.0
±4.0
VCC − VEE, SUPPLY VOLTAGE (V)
VS, SUPPLY VOLTAGE (V)
Figure 24. Output Voltage Swing versus
Supply Voltage
Figure 25. Gain and Phase Margin versus
Supply Voltage
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Φm, PHASE MARGIN (°)
20
RL = 10 k
AV = 100
TA = 25°C
Φm, PHASE MARGIN (°)
50
±5.0
NCS7101, NCV7101
20
VIO, INPUT OFFSET VOLTAGE (mV)
AVOL, OPEN LOOP GAIN (dB)
120
110
100
90
RL = 10 k
CL = 0
TA = 25°C
80
70
60
0
±1.0
±2.0
±3.0
±4.0
±5.0
VS = ±2.5 V
RL = ∞
CL = 0
AV = 1.0
TA = 25°C
15
10
5
0
−5
−10
−15
−20
−3.0
−2.0
Figure 26. Open Loop Voltage Gain versus
Supply Voltage (Split Supplies)
5
1.0
2.0
3.0
6.0
VS = ±0.9 V
RL = ∞
CL = 0
AV = 1.0
TA = 25°C
VCM, COMMON MODE INPUT
VOLTAGE RANGE (V)
VIO, INPUT OFFSET VOLTAGE (mV)
10
0
Figure 27. Input Offset Voltage versus Common
Mode Input Voltage Range, VS = +2.5 V
20
15
−1.0
VCM, COMMON VOLTAGE RANGE (V)
VS, SUPPLY VOLTAGE (V)
0
−5
−10
−15
−20
−1.0 −0.8 −0.6 −0.4 −0.2
0
0.2
0.4
0.6
0.8
4.0
2.0
DVIO = 5.0 mV
RL = ∞
CL = 0
AV = 1.0
TA = 25°C
0
−2.0
−4.0
−6.0
±0.5 ±1.0
1.0
VCM, COMMON MODE INPUT VOLTAGE (V)
±2.0
±3.0
±4.0
±5.0
VS, SUPPLY VOLTAGE (V)
Figure 28. Input Offset Voltage versus Common
Mode Input Voltage Range, VS = +0.9 V
Figure 29. Common−Mode Input Voltage Range
versus Power Supply Voltage
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NCS7101, NCV7101
APPLICATION INFORMATION AND OPERATING DESCRIPTION
GENERAL INFORMATION
The NCS7101 is a rail−to−rail input, rail−to−rail output
operational amplifier that features guaranteed 1.8 volt
operation. This feature is achieved with the use of a modified
analog CMOS process that allows the implementation of
depletion MOSFET devices. The amplifier has a 1.0 MHz
gain bandwidth product, 1.2 V/ms slew rate and is
operational over a power supply range less than 1.8 V to as
high as 10 V.
Cfb
Rfb
Input
Cin
+
Output
Cin = Input and printed circuit board capacitance
Figure 30. Input Capacitance Pole Cancellation
Inputs
The input topology of this device series is unconventional
when compared to most low voltage operational amplifiers.
It consists of an N−channel depletion mode differential
transistor pair that drives a folded cascode stage and current
mirror. This configuration extends the input common mode
voltage range to encompass the VEE and VCC power supply
rails, even when powered from a combined total of less than
1.8 volts. Figures 27 and 28 show the input common mode
voltage range versus power supply voltage.
The differential input stage is laser trimmed in order to
minimize offset voltage. The N−channel depletion mode
MOSFET input stage exhibits an extremely low input bias
current of less than 40 pA. The input bias current versus
temperature is shown in Figure 4. Either one or both inputs
can be biased as low as VEE minus 300 mV to as high as 10 V
without causing damage to the device. If the input common
mode voltage range is exceeded, the output will not display
a phase reversal but it may latch in the appropriate high or
low state. The device can then be reset by removing and
reapplying power. If the maximum input positive or
negative voltage ratings are to be exceeded, a series resistor
must be used to limit the input current to less than 2.0 mA.
The ultra low input bias current of the NCS7101 allows
the use of extremely high value source and feedback resistor
without reducing the amplifier’s gain accuracy. These high
value resistors, in conjunction with the device input and
printed circuit board parasitic capacitances Cin, will add an
additional pole to the single pole amplifier shown in
Figure 30. If low enough in frequency, this additional pole
can reduce the phase margin and significantly increase the
output settling time. The effects of Cin, can be canceled by
placing a zero into the feedback loop. This is accomplished
with the addition of capacitor Cfb. An approximate value for
Cfb can be calculated by:
Cfb +
Rin
Output
The output stage consists of complementary P and N
channel devices connected to provide rail−to−rail output
drive. With a 2.0 k load, the output can swing within 100 mV
of either rail. It is also capable of supplying over 95 mA
when powered from 10 V and 3.0 mA when powered from
1.8 V.
When connected as a unity gain follower, the NCS7101
can directly drive capacitive loads in excess of 390 pF at
room temperature without oscillating but with significantly
reduced phase margin. The unity gain follower
configuration exhibits the highest bandwidth and is most
prone to oscillations when driving a high value capacitive
load. The capacitive load in combination with the
amplifier’s output impedance, creates a phase lag that can
result in an under−damped pulse response or a continuous
oscillation. Figure 32 shows the effect of driving a large
capacitive load in a voltage follower type of setup. When
driving capacitive loads exceeding 390 pF, it is
recommended to place a low value isolation resistor
between the output of the op amp and the load, as shown in
Figure 31. The series resistor isolates the capacitive load
from the output and enhances the phase margin. Refer to
Figure 33. Larger values of R will result in a cleaner output
waveform but excessively large values will degrade the
large signal rise and fall time and reduce the output’s
amplitude. Depending upon the capacitor characteristics,
the isolation resistor value will typically be between 50 to
500 ohms. The output drive capability for resistive and
capacitive loads is shown in Figures 2, 3, and 23.
Input
Rin Cin
Rfb
+
-
R
Output
CL
Isolation resistor R = 50 to 500
Figure 31. Capacitance Load Isolation
Note that the lowest phase margin is observed at cold
temperature and low supply voltage.
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10
NCS7101, NCV7101
Figure 32. Small Signal Transient Response with Large Capacitive Load
Figure 33. Small Signal Transient Response with Large
Capacitive Load and Isolation Resistor.
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11
NCS7101, NCV7101
RT
470 k
VCC
Output Voltage
0
VCC
CT
1.0 nF
-
0.33 VCC
fO = 1.5 kHz
+
0.9 V
0.67 VCC
Timing Capacitor
Voltage
The non−inverting input threshold levels are set so that
the capacitor voltage oscillates between 1/3 and 2/3 of
VCC. This requires the resistors R1a, R1b and R2 to be of
equal value. The following formula can be used to approximate the output frequency.
R1a
470 k
R2
470 k
R1b
470 k
1
f +
O 1.39 R TC T
Figure 34. Square Wave Oscillator
cww
10 k
D1
1N4148
10 k
D2
1N4148
VCC
Output Voltage
0
1.0 M
Timing Capacitor
Voltage
0.67 VCC
0.33 VCC
cw
Clock−wise, Low Duty Cycle
VCC
CT
1.0 nF
VCC
Output Voltage
-
fO
+
0
Timing Capacitor
Voltage
R1a
470 k
0.67 VCC
0.33 VCC
Counter−Clock−wise, High Duty Cycle
VCC
R1b
470 k
R2
470 k
The timing capacitor CT will charge through diode D2 and discharge
through diode D1, allowing a variable duty cycle. The pulse width of the
signal can be programmed by adjusting the value of the trimpot. The capacitor voltage will oscillate between 1/3 and 2/3 of VCC, since all the
resistors at the non−inverting input are of equal value.
Figure 35. Variable Duty Cycle Pulse Generator
R1
1.0 M
2.5 V
R3
1.0 k
+
Cin
10 mF
≈
10,000 mF
−2.5 V
Ceff. +
R2
1.0 M
Figure 36. Positive Capacitance Multiplier
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R1
C
R3 in
NCS7101, NCV7101
Af
Cf
400 pF
Rf
100 k
fL
0.9 V
R2
10 k
1
f +
[ 200 Hz
L 2pR C
1 1
-
VO
+
Vin
C1
80 nF
fH
1
f +
[ 4.0 kHz
H 2pRC
f f
R1
10 k −0.9 V
R
A + 1 ) f + 11
f
R2
Figure 37. Voice Band Filter
Vsupply
VCC
Vin
+
I
-
V
in
+
sink R sense
Rsense
Figure 38. High Compliance Current Sink
Is
VL
1.0 W
Rsense
RL
5.0 V
R3
1.0 k
R4
R1
1.0 k
1.0 k
+
-
VO
R5
2.4 k
Is
VO
1.00 A
67.93 mV
0.50 A
78.67 mV
For best performance, use low
tolerance resistors.
R2
3.3 k
Figure 39. High Side Current Sense
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NCS7101, NCV7101
k R2
VCC
k R1
+
V
iL + S , Note that iL is independent of RL
R1
VO
-
R1
VS
R2
iL
RL
Figure 40. Current Source
R1
VCC
iS
-
VO
+
VO = −iS R1
Figure 41. Current to Voltage Converter
VCC
i=0
VS
-
RL
+
iL
VO
R1
V
V
iR1 + iL + R1 + S
R1
R1
iR1
Figure 42. Voltage to Current Converter
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NCS7101, NCV7101
R2
VCC
VO + V2
R1
V1
-
V2
VO
+
R3
ƪR3 R)4 R4ƫƪRR21 ) 1ƫ * V1 RR21
If R1 = R3, and R2 = R4, the equation simplifies to:
VO + (V2 * V1)
R4
R2
R1
Figure 43. Differential Amplifier
R4
R1
V2
V1
V2
VCC
R2
-
R3
VO
+
VO + * R 2
ƪRV11 ) RV22 ) RV33ƫ
To minimize input offset current take:
R5 = R1 // R2 // R3 // R4
R5
Figure 44. Summing Amplifier
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NCS7101, NCV7101
PACKAGE DIMENSIONS
TSOP−5
CASE 483−02
ISSUE H
D 5X
NOTE 5
2X
0.10 T
2X
0.20 T
NOTES:
1. DIMENSIONING AND TOLERANCING PER
ASME Y14.5M, 1994.
2. CONTROLLING DIMENSION: MILLIMETERS.
3. MAXIMUM LEAD THICKNESS INCLUDES
LEAD FINISH THICKNESS. MINIMUM LEAD
THICKNESS IS THE MINIMUM THICKNESS
OF BASE MATERIAL.
4. DIMENSIONS A AND B DO NOT INCLUDE
MOLD FLASH, PROTRUSIONS, OR GATE
BURRS.
5. OPTIONAL CONSTRUCTION: AN
ADDITIONAL TRIMMED LEAD IS ALLOWED
IN THIS LOCATION. TRIMMED LEAD NOT TO
EXTEND MORE THAN 0.2 FROM BODY.
0.20 C A B
M
5
1
4
2
L
3
B
S
K
DETAIL Z
G
A
DIM
A
B
C
D
G
H
J
K
L
M
S
DETAIL Z
J
C
0.05
SEATING
PLANE
H
T
MILLIMETERS
MIN
MAX
3.00 BSC
1.50 BSC
0.90
1.10
0.25
0.50
0.95 BSC
0.01
0.10
0.10
0.26
0.20
0.60
1.25
1.55
0_
10 _
2.50
3.00
SOLDERING FOOTPRINT*
0.95
0.037
1.9
0.074
2.4
0.094
1.0
0.039
0.7
0.028
SCALE 10:1
mm Ǔ
ǒinches
*For additional information on our Pb−Free strategy and soldering
details, please download the ON Semiconductor Soldering and
Mounting Techniques Reference Manual, SOLDERRM/D.
ON Semiconductor and
are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice
to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should
Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates,
and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death
associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal
Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
PUBLICATION ORDERING INFORMATION
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16
ON Semiconductor Website: www.onsemi.com
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For additional information, please contact your local
Sales Representative
NCS7101/D