Application Note
Choosing a Cry stal for VersaClock
®
7 Devices
R31AN0029EU0100 Rev.1.00
Nov 4, 2022
Page 1
© 2022 Renesas Electronics
This application note describes the crystal specifications requirements of VersaClock 7 devices. A list of
recommended crystals and approved vendors is also provid ed.
Contents
1. Introduction ................................................................................................................................................... 1
2. VersaClock 7 External Crystal Characteristics .......................................................................................... 1
3. List of Acceptable Crystals .......................................................................................................................... 2
4. Revision History ........................................................................................................................................... 3
1. Introduction
The VersaClock 7 RC310xxA/RC210xxA family relies on a crystal as the reference to the analog PLL. To
achieve optimum performance for a given application, the selection of the crystal must consider the nature of the
application as well as the specifications of the devices. For more details on the requirements for selecting a
crystal for timing applications, see the Choosing the Right Crystal for Clocking Devices application note. This
application note describes the requirements for selecting a crystal for the RC210xxA and RC310xxA fa mily of
devices. Refer to the latest datasheets (RC210xxA and RC310xxA) for up-to-date specific at ions of the
VersaClock 7 crystal input.
2. VersaClock 7 External Crystal Character istics
Table 1 shows the specifications for the crystal characteristics of the VersaClock 7 family of devices. To ensure
stable operation of the crystal oscillator circuitry of the device, choose a crystal with specifications that fall within
the requirements of the device.
Table 1. Exter nal Crystal Characteristics
Symbol
Parameter
Conditions
Typical
Maximum
Unit
-
Resonance Mode
-
Fundamental
-
f
INXTAL
[1]
Crystal input frequency
Funda me nta l mode
8 - 80
MHz
ESR
[1]
Equivalent Series
Resistance
8MHz ≤ f
INXTAL
≤ 12MHz, C
L
= 12pF .
- - 120
Ω
12MHz ≤ f
INXTAL
≤ 28MHz, C
L
= 12pF.
- - 80
28MHz �� f
INXTAL
≤ 54MHz, C
L
= 12pF.
-
50
54MHz ≤ f
INXTAL
≤ 80MHz, C
L
= 8pF.
-
50
C
O
[1]
Shunt Capacitance
-
7
-
pF
C
L
[1]
Load Capacitance
-
8
12
Drive
[1]
Drive Level
-
-
100
µW
Choosing a Crystal for VersaClock 7 Devices
R31AN0029EU0100 Rev.1.00
Nov 4, 2022
Page 2
Symbol
Parameter
Conditions
Typical
Maximum
Unit
F
TOL
Frequency Tolerance
Center frequen cy at 25ºC .
- -
[2] ppm
F
STAB
Frequency Stability
Over Operating Temperature Range
with respect to F
TOL.
- -
Aging
Per Year
-
-
1. These parameters are required regardless of the c ry st al use d.
2. These parameters are customer/application dependent. Common maximum values are F
TOL
= ±20ppm, and Aging =
±5ppm/10years. These parameters can be adjusted to meet pa rt ic ular requi rements.
3. Li st of Accep t able Crystal s
Table 2 prov ides a list of crys ta ls that would be acceptable for applications using a VersaClock 7 device. The
selection of the crystal frequency will depend on the application. For a clock synthesizer with outputs set at
100MHz, a 50MHz crystal would be recommended.
Table 2. Acceptable Crystals for Ver saClock 7 Applications
Manufacturer Part Number
Frequency
(MHz)
ESR (Ω)
C
L
(pF)
Drive Level
Rating (µW)
Frequency
Tolerance
(ppm)
Frequency
Stability
(ppm)
Aging
(ppm/year
at 25°C)
Temp
Range (ºC)
Specification - 8–80
50
(f>28MHz)
8–12 100 - - - -40 to 85
NDK
NX2016SA-80M
80
50
8
200
±15
±50
±3
-40 to 125
NDK
NX2016SA-50M
50
50
8
200
±15
±15
±3
-40 to 125
TXC
8Y78172001
78.125
40
8
100
±20
±30
±1
-40 to 105
TXC
8Z62572001
62.5
40
8
100
-5 to 12
-15 to 12
±1
-40 to 85
TXC
7M54072002
54
50
8
100
±12
±15
±3
-40 to 85
TXC
8Y60072005
60
40
8
300
-5 to 12
-15 to 12
±1
-40 to 85
TXC
8Y62572002
62.5
40
8
300
-5 to 12
-15 to 12
±1
-40 to 85
TXC
8Y68072001
68
40
8
300
-5 to 12
-15 to 12
±1
-40 to 85
TXC
8Y73072002
73
40
8
300
-5 to 12
-15 to 12
±1
-40 to 85
TXC
8Y78172002
78.125
40
8
300
-5 to 12
-15 to 12
±1
-40 to 85
TXC
8Y80072011
80
40
8
300
-5 to 12
-15 to 12
±1
-40 to 85
SIWARD
XTL581300-R110-
020
62.5 30 12 100 ±20 ±30 ±3 -40 to 105
SIWARD
XTL581300-R110-
006
73 30 12 100 ±20 ±30 ±3 -40 to 100
KYOCERA
CX3225SB49152
49.152
50
8
100
±15
±50
-
-40 to 125
KYOCERA
CX3225SB54000
54
50
8
100
±10
±15
±1
-30 to 85
KYOCERA
CX2016SA50000
50
50
8
200
±15
±50
-
-40 to 125
ECS
ECS-500-8-37-
AGN-TR
50 50 8 100 ±25 ±30 ±5 -40 to 85
Taitien
XXDBPLNANF-
40.000000
40 50 12 200 ±10 ±15 ±3 -40 to 85