LTC6906CS6#PBF Linear Technology, LTC6906CS6#PBF Datasheet - Page 8

• Manufacturer Part Number: LTC6906CS6#PBF
• Description: IC, PROG OSC, 1MHZ, 5.5V, TSOT-23-6
• Manufacturer: Linear Technology
• Type: Silicon Oscillatorr

Specifications of LTC6906CS6#PBF

• Mounting Style: Surface Mount
• Screening Level: Industrial
• Product Length (mm): 2.9mm
• Product Depth (mm): 1.75mm
• Product Height (mm): 0.9mm
• Package / Case: TSOT-23
• Frequency: 1MHz
• Supply Voltage Range: 2.25V To 5.5V
• Digital Ic Case Style: TSOT-23
• No. Of Pins: 6
• Operating Temperature Range: -40°C To +85°C
• Msl: MSL 1 - Unlimited
• Rohs Compliant: Yes
• Leaded Process Compatible: Yes
• Lead Free Status / RoHS Status: Compliant

LTC6906
APPLICATIONS INFORMATION
Selecting R
The LTC6906 contains a master oscillator followed by a
digital divider (see the Block Diagram). R
the master oscillator frequency and the DIV pin sets the
divider ratio, N. The range of frequencies accessible in
each divider ratio overlap, as shown in Figure 7. This figure
is derived from the equations in Table 1. For any given
frequency, power can be minimized by minimizing the
master oscillator frequency. This implies maximizing
R
relationship between R
consumption is shown in Figure 8, where we can clearly
see that supply current decreases for large values of R
For a discussion of jitter and divide ratio, refer to page 11.
Minimizing Power Consumption
The supply current of the LTC6906 has four current
components:
An approximate expression for the total supply current is:
V
temperature. This behavior is shown in the Typical Per-
formance Characteristics section.
Power can be minimized by maximizing R
the load on the OUT pin and operating at lower frequen-
cies. Figure 9 shows total supply current vs frequency
under typical conditions. Below 100kHz the load current
is negligible for the 5pF load shown.
8
I
+
SET
SET
≅ 5µA + 6 • I
• Constant (Independent V
• Proportional to I
• Proportional to V
• Proportional to V
≅ 5µA + 6 •
and using the lowest possible divider ratio, N. The
is approximately 650mV at 25°C, but varies with
SET
R
SET
V
SET
SET
and the Divider Ratio
+ V
+ V
+
SET
+
+
+
, ƒ
• ƒ
and R
SET
• ƒ
(which is the current in R
OUT
OUT
OUT
, N and the unloaded power
LOAD
and C
• C
+
, ƒ
(
• C
(
LOAD
OUT
LOAD
LOAD
and C
+ 5pF
+ 5pF
SET
SET
LOAD
)
+
, minimizing
)
determines
+
2 • R
)
2 • R
V
SET
LOAD
+
V
LOAD
+
SET
)
.
Figure 7. R
10000
1000
Figure 8. Unloaded Supply Current vs R
100
80
70
60
50
40
20
30
10
10
80
70
60
50
40
30
20
10
0
Figure 9. Supply Current vs Frequency
0
100
1
0
V
SET
+
MASTER OSCILLATOR FREQUENCY (kHz)
= 2.7V
200
vs Desired Output Frequency (LTC6906)
OUTPUT FREQUENCY (kHz)
10
10
400
3
R
100
SET
600
1
1
(k)
3
800
1000
10
C
V
T
1000
LOAD
+
A
= 3V
= 25C
6906 F09
6906 F07
6906 F08
= 0
10000
1200
1000
SET
6906fb