3

SP8715

Electrical Characteristics (Continued)

Guaranteed over the following conditions (unless otherwise stated):

Characteristic

Units

Conditions

Output level (pin 4)

500

600

mV p-p

20

ns

RF input = 1GHz

(notes 6,8)

1

ns

RF input = 1GHz

(notes 7,8)

10

µs

See Figure 9

6

µs

See Figure 9

(notes 7,8)

NOTES

2.

All electrical testing is performed at +85

°C.

3.

Typical values are measured at +25

4.

Modulus Control and Ratio Select are high impedance inputs which can be driven directly by standard

CMOS outputs.

5.

Modulus control is latched at the end of the previous cycle.

6.

See Figure 4.

7.

See Figure 8.

8.

These parameters are not tested but are guaranteee by design.

9.

The ratio select pin is not intended to be switched dynamically.

Value

Min.

Typ.

Max.

OPERATING NOTES

The RF inputs are biased internally and are normally

coupled to the signal source with suitable capaitors.

The output stage has a novel design and is intended

to drive a CMOS synthesiser input. External pull-down

resistors or circuits are not required. The SP8715 is

not suitable for driving TTL or similar devices.

The device will operate down to DC frequencies for

non-sinusoidal signals provided that the input slew

rate is better than 100V/

µs.

POWER DOWN (pin 7) is connected internally to a

pull-down resistor. If the battery economy facility is not

used, pin 7 should be either left unconnected or