IEEE Solid-States Circuits Magazine - Spring 2022 - 9
20
40
60
80
50
-40
-20
104
Loop Gain
Op Amp Gain
106
108
Frequency (Hz)
(a)
FIGURE 4: The magnitude and phase response of the uncompensated op amp.
the unity-gain bandwidth cannot
exceed this value after frequency
compensation is applied. It then
appears that the 1.1-GHz target stipulated
previously is far from reach. Fortunately,
pole splitting and pole-zero
cancellation resolve this issue.
Op-Amp Design
To obtain the widest bandwidth for a
given gain, we should incorporate a
cascode op amp, but, in view of the
low supply voltage, we opt for a simple
two-stage structure. The circuit
consists of a differential pair and a
stage with a current-mirror load, as
shown in Figure 3. Resistors Ra
Rb set the CM level at A and B, respecand
20
40
60
80
-40
-20
104
106
108
Frequency
(Hz)
(a)
FIGURE 6: The magnitude and phase response of the compensated op amp.
IEEE SOLID-STATE CIRCUITS MAGAZINE
SPRING 2022
9
1010
tively, while minimally loading these
nodes. This topology avoids cascodes
and creates well-defined bias
currents for both stages (e.g.,
copied from ),ID3
ID5
is
thus serving as a
robust solution. A transistor length of
120 nm provides a high voltage gain,
and a large channel area reduces the
flicker noise. The op amp draws a
supply current of
200An .
and M0
The LDO loop consisting of A1
contains poles at A (and B),
Q, P, and X. We therefore predict the
need for frequency compensation.
We simulate the open-loop LDO
circuit and arrive at the frequency
response depicted in Figure 4. Also
shown is the op-amp gain, i.e., from
-250
-200
-150
-100
-50
104
106
108
Frequency (Hz)
(b)
1010
VDD
M6
P
R Cc
c
500 1 pF Ω
R1
IVCO
FIGURE 5: The op-amp frequencycompensation
network.
CVCO
M0
X
the gates of M1
and M2
to node P.
From this, we me make two observations.
1) The loop gain falls to
unity at
f .,= 41GHz where the
1010
-300
-250
-200
-150
-100
-50
104
106
108
Frequency (Hz)
(b)
1010
Magnitude (dB)
Magnitude (dB)
Phase (°)
Phase (°)
IEEE Solid-States Circuits Magazine - Spring 2022
Table of Contents for the Digital Edition of IEEE Solid-States Circuits Magazine - Spring 2022
Contents
IEEE Solid-States Circuits Magazine - Spring 2022 - Cover1
IEEE Solid-States Circuits Magazine - Spring 2022 - Cover2
IEEE Solid-States Circuits Magazine - Spring 2022 - Contents
IEEE Solid-States Circuits Magazine - Spring 2022 - 2
IEEE Solid-States Circuits Magazine - Spring 2022 - 3
IEEE Solid-States Circuits Magazine - Spring 2022 - 4
IEEE Solid-States Circuits Magazine - Spring 2022 - 5
IEEE Solid-States Circuits Magazine - Spring 2022 - 6
IEEE Solid-States Circuits Magazine - Spring 2022 - 7
IEEE Solid-States Circuits Magazine - Spring 2022 - 8
IEEE Solid-States Circuits Magazine - Spring 2022 - 9
IEEE Solid-States Circuits Magazine - Spring 2022 - 10
IEEE Solid-States Circuits Magazine - Spring 2022 - 11
IEEE Solid-States Circuits Magazine - Spring 2022 - 12
IEEE Solid-States Circuits Magazine - Spring 2022 - 13
IEEE Solid-States Circuits Magazine - Spring 2022 - 14
IEEE Solid-States Circuits Magazine - Spring 2022 - 15
IEEE Solid-States Circuits Magazine - Spring 2022 - 16
IEEE Solid-States Circuits Magazine - Spring 2022 - 17
IEEE Solid-States Circuits Magazine - Spring 2022 - 18
IEEE Solid-States Circuits Magazine - Spring 2022 - 19
IEEE Solid-States Circuits Magazine - Spring 2022 - 20
IEEE Solid-States Circuits Magazine - Spring 2022 - 21
IEEE Solid-States Circuits Magazine - Spring 2022 - 22
IEEE Solid-States Circuits Magazine - Spring 2022 - 23
IEEE Solid-States Circuits Magazine - Spring 2022 - 24
IEEE Solid-States Circuits Magazine - Spring 2022 - 25
IEEE Solid-States Circuits Magazine - Spring 2022 - 26
IEEE Solid-States Circuits Magazine - Spring 2022 - 27
IEEE Solid-States Circuits Magazine - Spring 2022 - 28
IEEE Solid-States Circuits Magazine - Spring 2022 - 29
IEEE Solid-States Circuits Magazine - Spring 2022 - 30
IEEE Solid-States Circuits Magazine - Spring 2022 - 31
IEEE Solid-States Circuits Magazine - Spring 2022 - 32
IEEE Solid-States Circuits Magazine - Spring 2022 - 33
IEEE Solid-States Circuits Magazine - Spring 2022 - 34
IEEE Solid-States Circuits Magazine - Spring 2022 - 35
IEEE Solid-States Circuits Magazine - Spring 2022 - 36
IEEE Solid-States Circuits Magazine - Spring 2022 - 37
IEEE Solid-States Circuits Magazine - Spring 2022 - 38
IEEE Solid-States Circuits Magazine - Spring 2022 - 39
IEEE Solid-States Circuits Magazine - Spring 2022 - 40
IEEE Solid-States Circuits Magazine - Spring 2022 - 41
IEEE Solid-States Circuits Magazine - Spring 2022 - 42
IEEE Solid-States Circuits Magazine - Spring 2022 - 43
IEEE Solid-States Circuits Magazine - Spring 2022 - 44
IEEE Solid-States Circuits Magazine - Spring 2022 - 45
IEEE Solid-States Circuits Magazine - Spring 2022 - 46
IEEE Solid-States Circuits Magazine - Spring 2022 - 47
IEEE Solid-States Circuits Magazine - Spring 2022 - 48
IEEE Solid-States Circuits Magazine - Spring 2022 - 49
IEEE Solid-States Circuits Magazine - Spring 2022 - 50
IEEE Solid-States Circuits Magazine - Spring 2022 - 51
IEEE Solid-States Circuits Magazine - Spring 2022 - 52
IEEE Solid-States Circuits Magazine - Spring 2022 - 53
IEEE Solid-States Circuits Magazine - Spring 2022 - 54
IEEE Solid-States Circuits Magazine - Spring 2022 - 55
IEEE Solid-States Circuits Magazine - Spring 2022 - 56
IEEE Solid-States Circuits Magazine - Spring 2022 - 57
IEEE Solid-States Circuits Magazine - Spring 2022 - 58
IEEE Solid-States Circuits Magazine - Spring 2022 - 59
IEEE Solid-States Circuits Magazine - Spring 2022 - 60
IEEE Solid-States Circuits Magazine - Spring 2022 - 61
IEEE Solid-States Circuits Magazine - Spring 2022 - 62
IEEE Solid-States Circuits Magazine - Spring 2022 - 63
IEEE Solid-States Circuits Magazine - Spring 2022 - 64
IEEE Solid-States Circuits Magazine - Spring 2022 - 65
IEEE Solid-States Circuits Magazine - Spring 2022 - 66
IEEE Solid-States Circuits Magazine - Spring 2022 - 67
IEEE Solid-States Circuits Magazine - Spring 2022 - 68
IEEE Solid-States Circuits Magazine - Spring 2022 - 69
IEEE Solid-States Circuits Magazine - Spring 2022 - 70
IEEE Solid-States Circuits Magazine - Spring 2022 - 71
IEEE Solid-States Circuits Magazine - Spring 2022 - 72
IEEE Solid-States Circuits Magazine - Spring 2022 - 73
IEEE Solid-States Circuits Magazine - Spring 2022 - 74
IEEE Solid-States Circuits Magazine - Spring 2022 - 75
IEEE Solid-States Circuits Magazine - Spring 2022 - 76
IEEE Solid-States Circuits Magazine - Spring 2022 - 77
IEEE Solid-States Circuits Magazine - Spring 2022 - 78
IEEE Solid-States Circuits Magazine - Spring 2022 - 79
IEEE Solid-States Circuits Magazine - Spring 2022 - 80
IEEE Solid-States Circuits Magazine - Spring 2022 - 81
IEEE Solid-States Circuits Magazine - Spring 2022 - 82
IEEE Solid-States Circuits Magazine - Spring 2022 - 83
IEEE Solid-States Circuits Magazine - Spring 2022 - 84
IEEE Solid-States Circuits Magazine - Spring 2022 - 85
IEEE Solid-States Circuits Magazine - Spring 2022 - 86
IEEE Solid-States Circuits Magazine - Spring 2022 - 87
IEEE Solid-States Circuits Magazine - Spring 2022 - 88
IEEE Solid-States Circuits Magazine - Spring 2022 - 89
IEEE Solid-States Circuits Magazine - Spring 2022 - 90
IEEE Solid-States Circuits Magazine - Spring 2022 - 91
IEEE Solid-States Circuits Magazine - Spring 2022 - 92
IEEE Solid-States Circuits Magazine - Spring 2022 - 93
IEEE Solid-States Circuits Magazine - Spring 2022 - 94
IEEE Solid-States Circuits Magazine - Spring 2022 - 95
IEEE Solid-States Circuits Magazine - Spring 2022 - 96
IEEE Solid-States Circuits Magazine - Spring 2022 - 97
IEEE Solid-States Circuits Magazine - Spring 2022 - 98
IEEE Solid-States Circuits Magazine - Spring 2022 - 99
IEEE Solid-States Circuits Magazine - Spring 2022 - 100
IEEE Solid-States Circuits Magazine - Spring 2022 - 101
IEEE Solid-States Circuits Magazine - Spring 2022 - 102
IEEE Solid-States Circuits Magazine - Spring 2022 - 103
IEEE Solid-States Circuits Magazine - Spring 2022 - 104
IEEE Solid-States Circuits Magazine - Spring 2022 - 105
IEEE Solid-States Circuits Magazine - Spring 2022 - 106
IEEE Solid-States Circuits Magazine - Spring 2022 - 107
IEEE Solid-States Circuits Magazine - Spring 2022 - 108
IEEE Solid-States Circuits Magazine - Spring 2022 - 109
IEEE Solid-States Circuits Magazine - Spring 2022 - 110
IEEE Solid-States Circuits Magazine - Spring 2022 - 111
IEEE Solid-States Circuits Magazine - Spring 2022 - 112
IEEE Solid-States Circuits Magazine - Spring 2022 - 113
IEEE Solid-States Circuits Magazine - Spring 2022 - 114
IEEE Solid-States Circuits Magazine - Spring 2022 - 115
IEEE Solid-States Circuits Magazine - Spring 2022 - 116
IEEE Solid-States Circuits Magazine - Spring 2022 - 117
IEEE Solid-States Circuits Magazine - Spring 2022 - 118
IEEE Solid-States Circuits Magazine - Spring 2022 - 119
IEEE Solid-States Circuits Magazine - Spring 2022 - 120
IEEE Solid-States Circuits Magazine - Spring 2022 - Cover3
IEEE Solid-States Circuits Magazine - Spring 2022 - Cover4
https://www.nxtbook.com/nxtbooks/ieee/mssc_fall2023
https://www.nxtbook.com/nxtbooks/ieee/mssc_summer2023
https://www.nxtbook.com/nxtbooks/ieee/mssc_spring2023
https://www.nxtbook.com/nxtbooks/ieee/mssc_winter2023
https://www.nxtbook.com/nxtbooks/ieee/mssc_fall2022
https://www.nxtbook.com/nxtbooks/ieee/mssc_summer2022
https://www.nxtbook.com/nxtbooks/ieee/mssc_spring2022
https://www.nxtbook.com/nxtbooks/ieee/mssc_winter2022
https://www.nxtbook.com/nxtbooks/ieee/mssc_fall2021
https://www.nxtbook.com/nxtbooks/ieee/mssc_summer2021
https://www.nxtbook.com/nxtbooks/ieee/mssc_spring2021
https://www.nxtbook.com/nxtbooks/ieee/mssc_winter2021
https://www.nxtbook.com/nxtbooks/ieee/mssc_fall2020
https://www.nxtbook.com/nxtbooks/ieee/mssc_summer2020
https://www.nxtbook.com/nxtbooks/ieee/mssc_spring2020
https://www.nxtbook.com/nxtbooks/ieee/mssc_winter2020
https://www.nxtbook.com/nxtbooks/ieee/mssc_fall2019
https://www.nxtbook.com/nxtbooks/ieee/mssc_summer2019
https://www.nxtbook.com/nxtbooks/ieee/mssc_2019summer
https://www.nxtbook.com/nxtbooks/ieee/mssc_2019winter
https://www.nxtbook.com/nxtbooks/ieee/mssc_2018fall
https://www.nxtbook.com/nxtbooks/ieee/mssc_2018summer
https://www.nxtbook.com/nxtbooks/ieee/mssc_2018spring
https://www.nxtbook.com/nxtbooks/ieee/mssc_2018winter
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_winter2017
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_fall2017
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_summer2017
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_spring2017
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_winter2016
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_fall2016
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_summer2016
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_spring2016
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_winter2015
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_fall2015
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_summer2015
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_spring2015
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_winter2014
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_fall2014
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_summer2014
https://www.nxtbook.com/nxtbooks/ieee/solidstatecircuits_spring2014
https://www.nxtbookmedia.com