Fujitsu MB15F74UL Functional Description, Programmable Reference Counter, R10 R11 R12 R13 R14

MB15F74UL

■FUNCTIONAL DESCRIPTION

1. Pulse swallow function

fVCO = [ (P ⋅ N) + A] ⋅ fOSC ⎟ R

fVCO : Output frequency of external voltage controlled oscillator (VCO)

P: Preset divide ratio of dual modulus prescaler (32 or 64 for IF-PLL, 64or 128 for RF-PLL)

N : Preset divide ratio of binary 11-bit programmable counter (3 to 2,047)

A : Preset divide ratio of binary 7-bit swallow counter (0 ≤ A ≤ 127, A < N)

fOSC : Reference oscillation frequency (OSCIN input frequency)

R : Preset divide ratio of binary 14-bit programmable reference counter (3 to 16,383)

2.Serial Data Input

The serial data is entered using three pins, Data pin, Clock pin, and LE pin. Programmable dividers of IF/RF- PLL sections, programmable reference dividers of IF/RF-PLL sections are controlled individually.

The serial data of binary data is entered through Data pin.

On rising edge of Clock, one bit of the serial data is transferred into the shift register. On a rising edge of load enable signal, the data stored in the shift register is transferred to one of latches depending upon the control bit data setting.

	The programmable	The programmable	The programmable	The programmable
	reference counter	reference counter	counter and the swallow	counter and the swallow
	for the IF-PLL	for the RF-PLL	counter for the IF-PLL	counter for the RF-PLL
CN1	0	1	0	1
CN2	0	0	1	1

(1)Shift Register Configuration

•Programmable Reference Counter

(LSB)Data Flow (MSB)

1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23
CN1	CN2	T1	T2	R1	R2	R3	R4	R5	R6	R7	R8	R9	R10	R11	R12	R13	R14	CS	X	X	X	X

CS	: Charge pump current select bit
R1 to R14	: Divide ratio setting bits for the programmable reference counter (3 to 16,383)
T1, 2	: LD/fout output setting bit
CN1, 2	: Control bit

X: Dummy bits (Set “0” or “1”)

Note : Data input with MSB first.

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