Dual SPM Detector

Page 6 of 16

MX641 Preliminary Information

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3. External Components

XTAL

XTAL/CLOCK

XTAL/CLOCK

If you use a Clock Pulse input:

- Remove Xtal (X )

- Connect Pin 1 to V

- Do not short Pins 3 & 4

- Input clock pulses to CLOCK IN

See Figure 3

1

DD

CLOCK IN

IN

OUT

CLOCK

CH2 OUTPUT

CH1 OUTPUT

CH1 AMP IN (+)

C1

X1

R3

R1

R2

R4

R8

R6

C6

C5

R5

C3

C4

C2

R7

MX641

1

2

3

11

12

24

23

22

21

20

19

18

17

16

15

14

13

4

5

6

7

8

9

10

OUTPUT ENABLE

CH1 AMP OUT

CH1 AMP IN (-)

CH2 AMP OUT

OUTPUT SELECT

PRESET LEVEL

SERIAL CLOCK

SERIAL DATA

SYSTEM SELECT

CH2 AMP IN (-)

CH2 AMP IN (+)

CHIP SELECT

Figure 2: Recommended External Components

R1

68k

Ω

± 1%

C1

1.0µF

±20%

R2

68k

Ω

±1%

C2

1.0µF

±20%

R3

Note 1

750k

Ω

±1%

C3

270pF

±5%

R4

Note 1

750k

Ω

±1%

C4

270pF

±5%

R5

68k

Ω

± 1%

C5

270pF

±5%

R6

68k

Ω

± 1%

C6

270pF

±5%

R7

Note 1

750k

Ω

±1%

R8

Note 1

750k

Ω

±1%

X1

Note 2, 3

3.579545MHz

Table 2: Recommended External Components

Note:

1.

Fixed Sensitivity Setting: when calculating/selecting gain components, R3, R4, R7 and R8 should

always be greater than or equal to 100k

2.

For best results, a crystal oscillator design should drive the clock inverter input with signal levels of at

obtain crystal oscillator design assistance, consult your crystal manufacturer.

3.

The on-chip crystal circuitry includes a feedback resistor (nominally 2M

capacitors on pins 1 & 2 (nominally 10pF each, excluding package and board parasitics).