AS3689 datasheet(57/72 Pages) AMSOSRAM

57 / 72 page

AS3689

austriami crosyst ems

Datasheet, Confidential

www.austriamicrosystems.com (mlg, ptr)

Revision 1.0.2 / 20070115

55 - 70

The reset levels control the state of all registers. As long as VBAT and VDD_GPIO are below their reset

thresholds, the register contents are set to default. Access by serial interface is possible once the reset

thresholds are exceeded.

Table 24 – Reset Levels

Symbol

Parameter

Min

Typ

Max

Unit

Note

VPOR_VBAT

Overall Power-On

Reset

2.0

Monitor voltage on V2_5; power-on

reset for all internal functions.

VGPIO_Vdd_TH_RISI

Reset Level for

VDD_GPIO Rising

1.3

Monitor voltage on pin VDD_GPIO;

rising level.

VGPIO_vdd_TH_FAL

LING

Reset Level for

VDD_GPIO Falling

1.0

Monitor voltage on pin VDD_GPIO;

falling level.

7.9

Temperature Supervision

An integrated temperature sensor provides over-temperature protection for the AS3689. This sensor generates a

flag if the device temperature reaches the overtemperature threshold of 140º. The threshold has a hysteresis to

prevent oscillation effects.

If the device temperature exceeds the 140º threshold all current sources, the charge pump, the ldo and the dcdc

converter is disabled and the ov_temp flag is set. After decreasing the temperature by 5º (typically) operation is

resumed.

The ov_temp flag can only be reset by first writing a 1 and then a 0 to the (bit rst_ov_temp ).

Bit ov_temp_on = 1 activates temperature supervision.

Table 25 – Overtemperature Detection

Symbol

Parameter

Min

Typ

Max

Unit

Note

T140

ov_temp Rising Threshold

140

º C

Thyst

ov_temp Hystersis

º C

7.9.1 Temperature Supervision Registers

Addr: 29h

Overtemp Control

This register reads and resets the overtemperature flag.

Bit

Bit Name

Default

Access

Description

ov_temp_on

Activates/deactivates device temperature supervision.

Default: Off – all other bits are only valid if this bit is set to 1.

0 = Temperature supervision is disabled. No reset will be

generated if the device temperature exceeds 140ºC.

1 = Temperature supervision is enabled.

ov_temp

N/A

1 = Indicates that the overtemperature threshold has been

reached; this flag is not cleared by an overtemperature

reset. It has to be cleared using bit rst_ov_temp .

rst_ov_temp

R/W

The ov_temp flag is cleared by first setting this bit to 1, and

then setting this bit to 0.

7:4

N/A

AS3689 数据表(PDF) 57 Page - ams-OSRAM AG

AS3689 数据表(HTML) 57 Page - ams-OSRAM AG

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

数据表下载