The Smart Timing Choice



The Smart Timing Choice



SiT1618B

Standard Frequency, High Temperature Oscillator

Rev. 1.02

Page 2 of 13

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Notes:

1. In OE or ST mode, a pull-up resistor of 10 kΩ or less is recommended if pin 1 is not externally driven.

If pin 1 needs to be left floating, use the NC option.

2. A capacitor of value 0.1 µF or higher between Vdd and GND is required.

Table 1. Electrical Characteristics (continued)

Parameters

Symbol

Min.

Typ.

Max.

Unit

Condition

Input Characteristics

Input High Voltage

VIH

70%

–

–

Vdd

Pin 1, OE or ST

Input Low Voltage

VIL

–

–

30%

Vdd

Pin 1, OE or ST

Input Pull-up Impedance

Z_in

50

87

150

k



Pin 1, OE logic high or logic low, or ST logic high

2––

M



Pin 1, ST logic low

Startup and Resume Timing

Startup Time

T_start

–

–

5

ms

Measured from the time Vdd reaches its rated minimum value

Enable/Disable Time

T_oe

–

–

162

ns

f = 48 MHz. For other frequencies, T_oe = 100 ns + 3 * clock

periods

Resume Time

T_resume

–

–

5

ms

Measured from the time ST pin crosses 50% threshold

Jitter

RMS Period Jitter

T_jitt

–

1.6

2.5

ps

f = 20 MHz, Vdd = 2.5V, 2.8V, 3.0V or 3.3V

–

1.9

4

ps

f = 20 MHz, Vdd = 1.8V

Peak-to-peak Period Jitter

T_pk

–

12

20

ps

f = 20 MHz, Vdd = 2.5V, 2.8V, 3.0V or 3.3V

–

14

30

ps

f = 20 MHz, Vdd = 1.8V

RMS Phase Jitter (random)

T_phj

–

0.5

0.8

ps

f = 40 MHz, Integration bandwidth = 900 kHz to 7.5 MHz

–

1.3

2

ps

f = 40 MHz, Integration bandwidth = 12 kHz to 20 MHz

Table 2. Pin Description

Pin

Symbol

Functionality

1OE/ ST/NC

Output

Enable

L: output is high impedance. Only output driver is disabled.

Standby

L: output is low (weak pull down). Device goes to sleep mode. Supply

current reduces to I_std.

No Connect

output. Pin 1 has no function.

2

GND

Power

Electrical ground

3

OUT

Output

Oscillator output

4

VDD

Power

1

4

OE/ST/NC

VDD

3

2

GND

OUT

Figure 1. Pin Assignments

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