For customers designing NXP Semiconductors i.MX 6 family

Items to Confirm (designing of oscillation circuit)
Selection Guidance for crystal unit
Crystal Products Lineup
Oscillation Circuit and Selection Guidance of Crystal Unit.
Precautions for designing of PCB Board

We are pleased to introduce you to our crystal unit.

Items to Confirm (designing of oscillation circuit)

Please note: to design oscillation circuit, you need to confirm the electronic characteristics as follows:

Oscillation allowance and Negative resistance (-R):
You need to confirm oscillation capability.
We recommend the condition: (-R) / ESR > 5
* -R: Negative resistance, ESR: Equivalent Series Resistance

Drive Level:
You need to confirm if oscillation is stable, and if the drive level is within the specification.

Load Capacitance:
Load capacitance affects frequency stability, oscillation allowance, negative resistance, and start-up time of oscillation.
In addition the load capacitance is determinative factor of crystal unit's load capacitance (CL value) directly.

For details of each characteristic, please refer to the PDF file.

Precautions for Oscillation Circuit Design

Selection Guidance for crystal unit

When Customer selects crystal unit, load capacitance (CL value) is an important factor of the selection.
For instance, crystal with small CL(7.0 pF) makes larger oscillation allowance, smaller current consumption and worse frequency stability, like below table. Oppositely, crystal with large CL(12.5 pF) makes smaller oscillation allowance, larger current consumption and better frequency stability. Please select it in consideration of these characteristics.

Epson Crystal Product Lineups

Product	Size [mm]	Applications
MC-146	7.0 x 1.5 x 1.4	DSC, Consumer equipment, Radio equipment, Blood pressure meter, Blood-sugar monitor, Security systems
FC-135	3.2 x 1.5 x 0.9	PMP, DSC, Portable equipment
FC-13A	3.2 x 1.5 x 0.9	Automotive accessories and ECU sub clock
FA-238	3.2 x 2.5 x 0.7	- Mobile phone, Bluetooth, W-LAN - ISM band, Clock for MPU

Oscillation Circuit and Selection Guidance of Crystal Unit for i.MX Application processor

i.MX 6Quad, 6Dual, 6DualLite, 6Solo

1) 32 kHz Crystal

21 x 21mm BGA

	RTC_XTALI	RTC_XTALO
All Families	D9	C9

IC name	Product Name	Freq. [Hz]	CL ^*1 [pF]	f_tol ^*2 [ppm]	Product Code ^*3	External Parts ^*4			Package Size WxDxH [mm]
IC name	Product Name	Freq. [Hz]	CL ^*1 [pF]	f_tol ^*2 [ppm]	Product Code ^*3	Cg [pF]	Cd [pF]	Rf [Ω]	Package Size WxDxH [mm]
MCIMX6U5DVM10x	FC-135	32.768k	7.0	20	Q13FC13500002**	10	10	-	3.2 x 1.5 x 0.9
MCIMX6D5EYM10x	MC-146		12.5	20	Q13MC14620002**	22	22	10M	7.0 x 1.5 x 1.4
MCIMX6S6AVM08x	FC-13A		9.0	20	X1A0000910005**	18	18	10M	3.2 x 1.5 x 0.9

2) 24 MHz Crystal

21 x 21mm BGA

	XTALI	XTALO
All Families	A7	B7

IC name	Product Name	Freq. [Hz]	CL ^*1 [pF]	f_tol ^*2 [ppm]	Product Code ^*3	External Parts ^*4			Package Size WxDxH [mm]
IC name	Product Name	Freq. [Hz]	CL ^*1 [pF]	f_tol ^*2 [ppm]	Product Code ^*3	Cg [pF]	Cd [pF]	Rf [Ω]	Package Size WxDxH [mm]
MCIMX6S6AVM08x	FA-238	24M	10.0	20	Q22FA23801201**	5	5	-	3.2 x 2.5 x 0.7
MCIMX6Q6AVT10x				30	Q22FA23800817**	7	7	-
MCIMX6D6AVT10x						7	7	-
MCIMX6S6AVM08x						7	7	1M

Notes:*

*1. Load capacitance.
*2. Frequency tolerance (standard)
*3. Two digits of the product code is packing specification, please refer here for the detail.
*4. Above recommendations are based on actual evaluation results and intended to support users in picking the right components.
As the actual board layout and choice of external componentsinfluences the best suitable crystal load capacitance, We does not assume any responsibility and grant warranty for above recommendations.
Users design must be verified and decided by own and individual evaluation.
*5. Please evaluate a crystal oscillator without an external feedback resistor Rf if you need. It is possible that a crystal oscillator works without it because i.MX 6 series has an internal feedback resistor Rf in the MHz oscillator.

Precautions for designing of PCB Board

Layout of pins, Crystal unit, Capacitor and Resistor

-Please lay out crystal unit, capacitor and resistor near i.MX 6 as far as possible.
-The length of signal patterns in oscillatiton circuit should be as short as possible, and do not cross other signal lines.

GND Line Pattern and Interconnection of PCB

-Please lay out GND line pattern under crystal unit.
-In case of multi-layered PCB board, do not lay out other signal lines under crystal unit.