L9805 datasheet(27/103 Pages) STMICROELECTRONICS

27 / 103 page

27/103

L9805

The application board can improve noise reduction

in the chip connecting directly pin 42 to pin 9 and

pin 43 to pin 12 using traces as short as possible.

An additional capacitor mounted close to pin 9 and

12 can lead additional improvement.

4.2.1 VDD Short Circuit Protection

The output current of the digital voltage regulator

is controlled by a circuit that limits it to a maximum

value (IMAXVDD). When the output current exceeds

this value the VDD voltage starts falling down. Ex-

ternal loads must be chosen taking in account this

maximum current capability of the regulator.

4.3 Analog Section Power Supply

The analog supply voltage is available on VCC

pin. The external 100nF compensation capacitor

should be placed as close as possible to this pin

and AGND pin.

VCC is the reference voltage for the AD conver-

sion and must be used to supply ratiometric sen-

sors feeding AD inputs. Any voltage drop between

VCC pin and the sensor supply pin on the applica-

tion board, will cause the ADC to be inaccurate

when reading the sensor’s output.

4.3.1 VCC Short Circuit Protection

The output current of the analog voltage regulator

is controlled by a circuit that limits it to a maximum

value (IMAXVCC). When the output current exceeds

this value the VCC voltage starts falling down. Ex-

ternal loads must be chosen taking in account this

maximum current capability of the regulator.

WARNING: The pin VB2 is not short circuit pro-

tected so a short circuit on this pin will destroy the

device.

L9805 数据表(PDF) 27 Page - STMicroelectronics

L9805 数据表(HTML) 27 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载