欢迎访问ic37.com |
会员登录 免费注册
发布采购

ISL29038IROZ-T7 参数 Datasheet PDF下载

ISL29038IROZ-T7图片预览
型号: ISL29038IROZ-T7
PDF下载: 下载PDF文件 查看货源
内容描述: [Low Power Ambient Light and Proximity Sensor with Enhanced Infrared Rejection]
分类和应用: 光电二极管
文件页数/大小: 15 页 / 560 K
品牌: XICOR [ XICOR INC. ]
 浏览型号ISL29038IROZ-T7的Datasheet PDF文件第7页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第8页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第9页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第10页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第11页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第13页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第14页浏览型号ISL29038IROZ-T7的Datasheet PDF文件第15页  
ISL29038  
0x04[4]) is set and then clear the flag by writing ‘0’ to Reg  
0x04[4].  
IR penetrates into the skin and is reflected from within. As a result,  
the proximity count generally peaks at contact and monotonically  
decreases as skin moves away. The reflective characteristics of  
skin are very different from that of a inanimate object such as  
paper.  
Following power-up, a ‘Brown-Out’ condition, if detected, is  
reported by PWR_FAIL flag by Reg 0x04[4]. Device configuration  
registers are not set to their power-up default after ‘Brown-Out’.  
PWR_FAIL flag should be periodically monitored to detect post  
power-up power supply interruption.  
Typical Application Circuit  
A typical application circuit for the ISL29038 is shown in  
2
Power-Down  
Figure 12. The ISL29038’s I C address is internally hard wired as  
‘1000100x’, with x representing the R/W bit. The device can be  
Setting ALS_EN (Reg 0x02[2]) and PROX_EN (Reg 0x01[5]) to ‘0’  
puts the ISL29038 into a power-down state with power supply  
current dropping to less than 1µA. All configuration registers are  
maintained in power-down mode.  
2
2
connected to a system’s I C bus together with other I C  
compliant devices. It is important to ensure that there is no  
2
address conflict with other I C devices on the bus.  
The SCL, SDA and INT pins on ISL29038 are open drain and  
require pull-up resistors for proper system operation. Values of  
the pull-up resistors is system dependent and can range from  
2.2k to 10k depending upon the number of I C devices on the  
bus.  
Soft Reset  
A software reset to ISL29038 can be initiated by writing 0x38 to  
Reg 0x0E. Following reset, all configuration registers are set to  
their default power-up state. After soft reset, the ISL29038  
defaults to the power-down configuration.  
2
The proximity sensing system can be powered using a dual power  
supply or using a single power supply. In dual supply  
configuration, the IR LED and the ISL29038 are powered from  
ALS Data Count Read Out  
2
st  
A 2 byte I C read from ALS_DATA_HB outputs MSB 1 data on  
SDA. This data is LSB justified with a zero fill for unused bits.  
Note that the MSB byte address precedes the LSB byte address.  
The ALS count is 256*(ALS_DATA_HB) + ALS_DATA_LB.  
separate power supplies. The V IRLED can range from 2.25V to  
DD  
5.0V and the V _ANALOG can range from 2.25V to 3.63V. In  
DD  
dual supply configuration, resistor R should not be installed.  
2
In single supply configuration, the IR LED and the ISL29038 are  
Proximity Detection of Various Objects  
powered from the same power source. The V _IRLED can range  
from 2.25V to 3.63V and the V _Analog is derived from  
DD  
DD  
Proximity sensing relies on the amount of IR reflected back from  
objects. A perfect black object would absorb all incident light and  
reflect no photons. The ISL29038 is sensitive enough to detect  
black ESD foam, which reflects only 1% of IR. Blonde hair typically  
reflects more than brown hair and skin tissue is more reflective  
than human hair.  
V
_IRLED using resistor R .  
DD  
2
In either power supply configuration, a 1µF decoupling capacitor  
should be installed close to the AVDD pin, and another 1µF  
decoupling capacitor should be placed close to the IR LED anode.  
VDD_PULLUP  
VDD_IRLED  
SCL, SDA AND  
INT PULLUPs  
D
IRLED  
IRDR  
INT  
SDA  
SCL  
1
R
100  
C
1µF  
2
1
U1  
SMBus MASTER  
1
2
3
4
8
7
6
5
GNDIR  
AVDD  
AGND  
RExt  
INT  
SDA  
SCL  
VDD_ANALOG  
C
2
1µF  
ISL29038  
R
1
499k  
R : 499k 1% RESISTOR  
1
R : 1005% RESISTOR  
2
C , C : 1µF CERAMIC 10V CAPACITOR  
1
2
D : OSRAM SFH4650 INFRARED LED  
1
FIGURE 12. TYPICAL APPLICATIONS CIRCUIT  
FN7851.0  
October 12, 2012  
12