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# LM10011 View Datasheet(PDF) - Texas Instruments

 Part Name Description Manufacturer LM10011 6/4-Bit VID Programmable Current DAC for Point of Load Regulators with Adjustable Start-Up Current Texas Instruments
LM10011 Datasheet PDF : 24 Pages
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www.ti.com
LM10011
SNVS822A – DECEMBER 2012 – REVISED NOVEMBER 2014
1.1V
=
.6V
x
1+
6.81k
RFB2
-0V
(6)
RFB2 = 8.1k
(7)
Using 1% standard resistor values, RFB2 can be set to 8.06 kΩ. This will yield a regulator output range of 0.704 V
(CODE 0d) to 1.107 V (CODE 63d). Values calculated here will be dependent on the accuracy of the regulator,
the LM10011 IDAC_OUT, and the resistor values used in the circuit.
Table 5 shows the codes and some of the resultant values of the IDAC current and the corresponding regulator
output voltage for the previous example.
Table 5. 6-Bit VID Codes with IDAC Current and Regulator Voltage for the Example in Figure 12.
VID CODE
000000b (0d)
000001b (1d)
000010b (2d)
000011b (3d)
....
111100b (60d)
111101b (61d)
111110b (62d)
111111b (63d)
IDAC_OUT CURRENT (µA)
59.2
58.3
57.4
56.4
....
2.87
1.93
1.00
0.06
REGULATOR VOLTAGE (V)
0.704
0.710
0.716
0.729
....
1.087
1.094
1.100
1.107
The required IDAC_OUT value during start-up can be calculated based on the desired start-up voltage of 1.05 V
and the RFB1 and RFB2 resistors found in the previous calculations. Using Equation 3 to solve for the required
start-up IDAC_OUT current results in a start-up current of 8.36 µA.
IDAC_OUT =
1
6.81k
0.6V x 1+68..0861kk
- 1.05V
= 8.36µA
(8)
Choose a resistor in Table 2 that selects a start-up code that produces a current close to 8.36 µA. An RSET of
215 kΩ selects a nominal start-up code of 13d yielding a current of 7.59 µA and start-up voltage of 1.054 V.
NOTE
Using an RSET of 215 kΩ may also select a code of 14d (+1 LSB) yielding a current of 3.80
µA and a start-up voltage of 1.081 V.
8.2.3 Application Curves
1.14
1.11
1.08
1.05
1.02
0.99
0.96
0.93
0.9
0.87
0.84
0.81
0.78
0.75
0.72
0.69
0
VIN = 2.9V
VIN = 5.5V
5 10 15 20 25 30 35 40 45 50 55 60 65
6-Bit VID Code (Decimal)
Figure 13. Output Voltage vs. Code for LM21k with LM10011