LTC6990IS6#TRPBF Linear Technology, LTC6990IS6#TRPBF Datasheet - Page 11

• Manufacturer Part Number: LTC6990IS6#TRPBF
• Description: IC MPU SUPERVISORY TSOT23-6
• Manufacturer: Linear Technology

Specifications of LTC6990IS6#TRPBF

• Frequency: *
• Voltage - Supply: *
• Current - Supply: 235µA
• Operating Temperature: *
• Package / Case: TSOT-23-6, TSOT-6
• Count: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

OPERATION
Table 1. DIVCODE Programming
Table 1 offers recommended 1% resistor values that ac-
curately produce the correct voltage division as well as the
corresponding N
resistor pairs. Other values may be used as long as:
1. The V
2. The driving impedance (R1||R2) does not exceed
If the voltage is generated by other means (i.e. the output
of a DAC) it must track the V
tor tolerances and temperature effects)
500kΩ.
DIVCODE
10
11
12
13
14
15
0
1
2
3
4
5
6
7
8
9
DIV
/V
+
ratio is accurate to ±1.5% (including resis-
DIV
Hi-Z
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
and Hi-Z values for the recommended
1000
100
0.1
10
1
0V
+
0
N
128
128
16
32
64
64
32
16
supply voltage. The last
DIV
1
2
4
8
8
4
2
1
1
Figure 2. Frequency Range and Hi-Z Bit vs DIVCODE
2
Hi-Z BIT = 0
3
1.953kHz to 31.25kHz
1.953kHz to 31.25kHz
3.906kHz to 62.5kHz
976.6Hz to 15.63kHz
488.3Hz to 7.813kHz
488.3Hz to 7.813kHz
976.6Hz to 15.63kHz
3.906kHz to 62.5kHz
Recommended f
31.25kHz to 500kHz
15.63kHz to 250kHz
7.813kHz to 125kHz
7.813kHz to 125kHz
15.63kHz to 250kHz
31.25kHz to 500kHz
4
62.5kHz to 1MHz
62.5kHz to 1MHz
5
6
INCREASING V
7
OUT
0.5•V
8
column in Table 1 shows the ideal ratio of V
supply voltage, which can also be calculated as:
For example, if the supply is 3.3V and the desired DIVCODE
is 4, V
Figure 2 illustrates the information in Table 1, showing that
N
+
DIV
DIV
V
9
V
DIV
is symmetric around the DIVCODE midpoint.
+
DIV
10
R1 (k)
=
Short
Open
1000
1000
1000
1000
1000
Hi-Z BIT = 1
976
976
887
681
523
392
280
182
102
= 0.281 • 3.3V = 928mV ± 50mV.
11
DIVCODE + 0.5
RECOMMENDED RANGE
EXTENDED RANGE
12
16
13
R2 (k)
14
Short
Open
1000
1000
1000
1000
1000
102
182
280
392
523
681
887
976
976
6990 F02
15
V
± 1.5%
+
≤ 0.03125 ±0.015
≥ 0.96875 ±0.015
0.09375 ±0.015
0.15625 ±0.015
0.21875 ±0.015
0.28125 ±0.015
0.34375 ±0.015
0.40625 ±0.015
0.46875 ±0.015
0.53125 ±0.015
0.59375 ±0.015
0.65625 ±0.015
0.71875 ±0.015
0.78125 ±0.015
0.84375 ±0.015
0.90625 ±0.015
LTC6990
V
DIV
/V
+
DIV
11
to the
6990f