FUJITSU MB88152A, MB88152A-100, MB88152A-101, MB88152A-102, MB88152A-110 DATA SHEET

	FUJITSU MICROELECTRONICS		DS04-29125-2Ea
	DATA SHEET

Spread Spectrum Clock Generator

MB88152A

MB88152A-100/101/102/110/111/112

■ DESCRIPTION

MB88152A is a clock generator for EMI (Electro Magnetic Interference) reduction. The peak of unnecessary radiation noise (EMI) can be attenuated by making the oscillation frequency slightly modulate periodically with the internal modulator. It corresponds to both of the center spread which modulates input frequency as Middle Centered and down spread which modulates so as not to exceed input frequency.

■FEATURES

•Input frequency : 16.6 MHz to 134 MHz

•Output frequency : 16.6 MHz to 134 MHz

•Modulation rate : ± 0.5%, ± 1.5% (Center spread), − 1.0%, − 3.0% (Down spread)

•Equipped with oscillation circuit: Range of oscillation 16.6 MHz to 48 MHz

•Modulation clock output Duty : 40% to 60%

•Modulation clock Cycle-Cycle Jitter : Less than 100 ps

•Low current consumption by CMOS process : 5.0 mA (24 MHz : Typ-sample, no load)

•Power supply voltage : 3.3 V ± 0.3 V

•Operating temperature : − 40 °C to +85 °C

•Package : SOP 8-pin

Copyright©2007-2008 FUJITSU MICROELECTRONICS LIMITED All rights reserved 2007.6

MB88152A

■ PRODUCT LINE-UP

MB88152A has three kinds of input frequency, and two kinds of modulation type (center/down spread), total six lineups.

Product	Input/Output Frequency	Modulation type	Modulation enable pin
MB88152A-100	16.6 MHz to 134 MHz		No
MB88152A-101	16.6 MHz to 67 MHz	Down spread	Yes
MB88152A-102	40 MHz to 134 MHz
MB88152A-110	16.6 MHz to 134 MHz		No
MB88152A-111	16.6 MHz to 67 MHz	Center spread	Yes
MB88152A-112	40 MHz to 134 MHz

■ PIN ASSIGNMENT

TOP VIEW

XIN	1		8	XENS	XIN	1		8	FREQ1
XOUT 2		MB88152A-101	7	FREQ	XOUT 2			7	FREQ0
		MB88152A-102					MB88152A-100
VSS	3	MB88152A-111	6	VDD	VSS	3	MB88152A-110	6	VDD
		MB88152A-112
SEL	4		5	CKOUT	SEL	4		5	CKOUT

FPT-8P-M02 FPT-8P-M02

■ PIN DESCRIPTION

Pin name	I/O	Pin no.	Description
XIN	I	1	Crystal resonator connection pin/clock input pin
XOUT	O	2	Crystal resonator connection pin
VSS		3	GND pin
SEL	I	4	Modulation rate setting pin
CKOUT	O	5	Modulated clock output pin
VDD		6	Power supply voltage pin
FREQ/FREQ0	I	7	Frequency setting pin
XENS/FREQ1	I	8	Modulation enable setting pin/frequency setting pin

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MB88152A

■ I/O CIRCUIT TYPE

Pin

Circuit type

Remarks

CMOS hysteresis input

SEL

FREQ

FREQ0

FREQ1

XENS

• CMOS output

• IOL = 4 mA

CKOUT

Note : For XIN and XOUT pins, refer to “■OSCILLATION CIRCUIT”.

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MB88152A

■ HANDLING DEVICES

Preventing Latch-up

A latch-up can occur if, on this device, (a) a voltage higher than VDD or a voltage lower than VSS is applied to an input or output pin or (b) a voltage higher than the rating is applied between VDD and VSS pins. The latch-up, if it occurs, significantly increases the power supply current and may cause thermal destruction of an element. When you use this device, be very careful not to exceed the maximum rating.

Handling unused pins

Do not leave an unused input pin open, since it may cause a malfunction. Handle by, using a pull-up or pull-down resistor.

Unused output pin should be opened.

The attention when the external clock is used

Input the clock to XIN pin, and XOUT pin should be opened when you use the external clock.

Please pay attention so that an overshoot and an undershoot do not occur to an input clock of XIN pin.

Power supply pins

Please design connecting the power supply pin of this device by as low impedance as possible from the current supply source.

We recommend connecting electrolytic capacitor (about 10 µF) and the ceramic capacitor (about 0.01 µF) in parallel between VSS and VDD pins near the device, as a bypass capacitor.

Oscillation Circuit

Noise near the XIN and XOUT pins may cause the device to malfunction. Design printed circuit boards so that electric wiring of XIN or XOUT pin and resonator (or ceramic oscillator) do not intersect other wiring.

Design the printed circuit board that surrounds the XIN and XOUT pins with ground.

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MB88152A

■ BLOCK DIAGRAM

VDD

SEL	Modulation rate setting
	Frequency setting
FREQ/FREQ0
	Modulation enable /	PLL block	CKOUT
	Frequency setting
XENS/FREQ1			Clock output
XOUT	Reference clock
XIN	Rf = 1 MΩ

VSS

	1
	−
	M
	Phase	Charge	V/I	IDAC	ICO
	compare	pump	conversion
					Modulation
Reference
	1		Loop filter		clock
clock	−				output
	N

						Modulation
		1
		−			Modulation logic	rate setting/
		L
			MB88152A PLL block			Modulation
						enable setting

A glitchless IDAC (current output D/A converter) provides precise modulation, thereby dramatically reducing EMI.

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MB88152A

■ PIN SETTING

When changing the pin setting, the stabilization wait time for the modulation clock is required. The stabilization wait time for the modulation clock takes the maximum value of Lock-Up time in “■ ELECTRICAL CHARACTERISTICS • AC characteristics Lock-Up time”.

Modulation enable setting

XENS		Modulation
L	Modulation		MB88152A-101, MB88152A-102,
H	No modulation		MB88152A-111, MB88152A-112

Note : MB88152A-100 and MB88152A-110 do not have XENS pin.

SEL modulation rate setting

SEL			Modulation rate		Remarks
		± 0.5%		MB88152A-110,
				MB88152A-111,	Center spread
L				MB88152A-112
		− 1.0%		MB88152A-100,
				MB88152A-101,	Down spread
				MB88152A-102
		± 1.5%		MB88152A-110,
				MB88152A-111,	Center spread
H				MB88152A-112
		− 3.0%		MB88152A-100,
				MB88152A-101,	Down spread
				MB88152A-102

Note : The modulation rate can be changed at the level of the terminal.

Frequency setting

FREQ					Frequency
L				16.6 MHz to 40 MHz		MB88152A-101, MB88152A-111
				40 MHz to 80 MHz		MB88152A-102, MB88152A-112
H				33 MHz to 67 MHz		MB88152A-101, MB88152A-111
				66 MHz to 134 MHz		MB88152A-102, MB88152A-112
Note : MB88152A-100 and MB88152A-110 do not have FREQ pin.
Frequency setting
FREQ1		FREQ0			Frequency
L		L		16.6 MHz to 40 MHz
L		H		33 MHz to 67 MHz		MB88152A-100, MB88152A-110
H		L		40 MHz to 80 MHz
H		H		66 MHz to 134 MHz

Note : MB88152A-101, MB88152A-111, MB88152A-102 and MB88152A-112 have neither FREQ0 pin nor FREQ1 pin.

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MB88152A

• Center spread

Spectrum is spread (modulated) by centering on the input frequency.

3.0% modulation width
Radiation level
−1.5%	+1.5%
	Frequency
Input frequency
Center spread example of	± 1.5% Modulation rate

• Down spread

Spectrum is spread (modulated) below the input frequency.

3.0% modulation width
Radiation level
−3.0%
	Frequency
Input frequency
Down spread example of	− 3.0% Modulation rate

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MB88152A

■ ABSOLUTE MAXIMUM RATINGS

	Parameter	Symbol	Rating		Unit
			Min	Max
	Power supply voltage*	VDD	− 0.5	+ 4.0	V
	Input voltage*	VI	VSS − 0.5	VDD + 0.5	V
	Output voltage*	VO	VSS − 0.5	VDD + 0.5	V
	Storage temperature	TST	− 55	+ 125	°C
	Operation junction temperature	TJ	− 40	+ 125	°C
	Output current	IO	− 14	+ 14	mA
	Overshoot	VIOVER		VDD + 1.0 (tOVER ≤ 50 ns)	V
	Undershoot	VIUNDER	VSS − 1.0 (tUNDER ≤ 50 ns)		V

* : The parameter is based on VSS = 0.0 V.

WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings.

Overshoot/Undershoot

						tUNDER ≤ 50 ns
	VIOVER ≤ VDD + 1.0 V
											VDD
	Input pin										VSS
	tOVER ≤ 50 ns					VIUNDER ≤ VSS − 1.0 V

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