DATASHEET

ISL29000
Data Sheet
September 2, 2008
FN6117.6
Ambient Light Photo Detect IC
Features
The ISL29000 is a light-to-current optical sensor combining
a photodiode and a current amplifier on a single monolithic
IC. Output current is directly proportionate to the light
intensity on the photodiode. Its sensitivity is superior to that
of a phototransistor and exhibits little variation. Its spectral
sensitivity matches closely to the luminous efficiency and
linearity.
• Monolithic IC containing photodiode and amplifier
Housed in an ultra-compact surface mount clear plastic
package, this device is excellent for power saving control
function in cell phones, PDAs, and other handheld
applications.
• Ultra-compact and light surface mount package
Pinout
• Mobile phones
• Converts light intensity to current
• 2.5V to 5.5V supply range
• Low supply current: 1µA
• Excellent output linearity of luminance
• Pb-free (RoHS compliant)
Applications
• Notebook PCs
ISL29000
(5 LD ODFN)
TOP VIEW
• PDAs
• Video cameras
VCC 1
GND 2
5 OUTPUT
THERMAL
PAD
• Digital cameras
Ordering Information
4 NC
EN 3
*THERMAL PAD CAN BE CONNECTED TO GND OR
ELECTRICALLY ISOLATED
PART NUMBER
(Note)
ISL29000IROZ-T7*
TEMP RANGE
(°C)
-40 to +85
PACKAGE
(Pb-Free)
PKG.
DWG. #
5 Ld ODFN
L5.2X2.1
Tape and Reel
ISL29000IROZ-EVALZ Evaluation Board
*Please refer to TB347 for details on reel specifications.
NOTE: These Intersil Pb-free plastic packaged products employ
special Pb-free material sets; molding compounds/die attach
materials and 100% matte tin plate - e3 termination finish, which is
RoHS compliant and compatible with both SnPb and Pb-free
soldering operations. Intersil Pb-free products are MSL classified at
Pb-free peak reflow temperatures that meet or exceed the Pb-free
requirements of IPC/JEDEC J STD-020.
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2005-2008. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
ISL29000
Absolute Maximum Ratings (TA = +25°C)
Thermal Information
Supply Voltage between VSD and GND . . . . . . . . . . . . . . . . . . . .6V
Maximum Continuous Output Current . . . . . . . . . . . . . . . . . . . . 6mA
Operating Temperature . . . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C
Thermal Resistance
θJA (°C/W)
ODFN Package . . . . . . . . . . . . . . . . . . . . . . . . . . . .
90
Maximum Die Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . +90°C
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-40°C to +100°C
Pb-free reflow profile . . . . . . . . . . . . . . . . . . . . . . . . . .see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and
result in failures not covered by warranty.
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests
are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA
VCC = 3V, TA = +25°C, unless otherwise specified.
Electrical Specifications
PARAMETER
ICC
DESCRIPTION
CONDITION
Supply Current
MIN
TYP
MAX
UNIT
RL = 1kΩ, EV = 1000 lux
74
µA
EV = 0
0.2
µA
IL1
Light Current
EV = 1000 lux
IL2
Light Current
EV = 100 lux
6.5
µA
ILEAK
Dark Current
EV = 0
0.06
µA
Maximum Output Compliance Voltage
At 95% of normal output current,
EV = 1000 lux
2.7
V
tR
Rise Time (Note 1)
RL = 5kΩ, EV = 1000 lux
27
µs
tF
Fall Time (Note 1)
RL = 5kΩ, EV = 1000 lux
78
µs
tD
Delay Time for Rising Edge (Note 1)
RL = 5kΩ, EV = 1000 lux
80
µs
tS
Delay Time for Falling Edge (Note 1)
RL = 5kΩ, EV = 1000 lux
35
µs
VO(MAX)
VLO
Maximum Voltage at EN Pin to Enable
VHI
Minimum Voltage at EN Pin to Disable
45
61
75
0.6
1.8
µA
V
V
NOTE:
1. Switching time measurement is based on Figures 1 and 2.
2. Fluorescent light is substituted by Green LED during production.
PULSE DRIVE
CH1
tD
VCC
1V
PULSE
DRIVE
ISL29000
80%
0.1V
RL
CH2
VOUT
tR
2
tS
VS = 3V
tA = +27°C
VOUT
FIGURE 1. RISE/FALL TIME MEASUREMENT
100µs
20%
tF
FIGURE 2. RISE/FALL TIME MEASUREMENT WAVEFORMS
FN6117.6
September 2, 2008
ISL29000
Typical Performance Curves
70
ISL29000 RELATIVE RESPONSE
VCC = 3V
FLUORESCENT LIGHT
60
OUTPUT CURRENT (µA)
RELATIVE RESPONSE (%)
100
80
60
40
ISL29000 RELATIVE
RESPONSE WITH IR
GLASS FILTER
20
50
40
30
20
10
0
0
400
500
600
700
800
900
0
1k
200
WAVE LENGTH (nm)
0.20
1000
1.20
VDD = 3V
VDD = 3V
1.15 FLUORESCENT LIGHT OF 500 LUX
0.18
0.16
0.14
1.10
1.05
1.00
0.95
0.90
0.12
0.85
0.10
-60
-40
-20
0
20
40
60
80
0.80
-60
100
-40
-20
TEMPERATURE (°C)
20
40
60
80
100
FIGURE 6. GAIN vs TEMPERATURE
800
0.6
0.5
0
TEMPERATURE (°C)
FIGURE 5. DARK CURRENT vs TEMPERATURE
VDD = 3V
TA = +27°C
700
600
0.4
IOUT (µA)
OUTPUT COMPLIANCE VOLTAGE
(VDD - VOUT) (V)
800
FIGURE 4. SENSITIVITY
GAIN/GAIN (+25°C)
OUTPUT CURRENT - NO LIGHT (µA)
FIGURE 3. SPECTRAL RESPONSE
400
600
ILLUMINATION (LX)
0.3
0.2
500
400
FLUORESCENT
LIGHT SOURCE
300
200
0.1
0
-200
100
0
0
200
400
600
800
1000
1200
OUTPUT CURRENT (µA)
FIGURE 7. OUTPUT COMPLIANCE VOLTAGE vs CURRENT
3
0
5k
10k
15k
20k
ILLUMINANCE (lux)
FIGURE 8. IOUT vs LUMINANCE
FN6117.6
September 2, 2008
ISL29000
For some applications, a load resistor is added between the
output and the ground as shown in Figure 1. The output
voltage can be expressed in Equation 2:
Pin Descriptions
PIN
NAME
DESCRIPTION
1
VCC
Supply, 2.5V to 5.5V
2
GND
Ground
3
EN
Enable
4
NC
No connect
5
Output
61μA
V OUT = I OUT × R LOAD = ⎛ ------------------------⎞ × L INPUT × R LOAD
⎝ 1000Lux⎠
(EQ. 2)
Here, VOUT is the output voltage and RLOAD is the value of
the load resistor added. The compliance of the ISL29000's
output circuit may result in premature saturation of the
output current and voltage when an excessively large
RLOAD is used. The output compliance voltage is 300mV
below the supply voltage as listed in VO(MAX) of “Electrical
Specifications” on page 2.
Current output pin
Block Diagram
VCC
1
In order to have the linear relationship between the input
light and the output current and voltage, a proper resistor
value (i.e., gain) should be picked for a specific input light
range. The resistor value can be picked according to
Equation page 4:
3
ENABLE
( V SUP – 0.3V ) 1000Lux
- × -----------------------R LOAD = -------------------------------------·
L RANGE
61 μA
5
(EQ. 3)
OUTPUT
Here, VSUP is the supply voltage, and LRANGE is the
specific input light range for an application. For example, an
indoor light ranges typically from 0 lux to 1,000 lux. A resistor
value of 45kΩ for 3V supply voltage can be used. For a small
light range, a large resistor value should be used to achieve
better sensitivity; for a large light range, a small resistor
value should be used to prevent non-linear output current
and voltage.
2
GND
Application Information
Product Description
Resistor Output RLOAD Selection
The ISL29000 is a light-to-current optical sensor combining
photodiodes and current amplifiers on a single monolithic IC.
The photodiodes are temperature-compensated and their
spectrum resembles the human eye response. The output
current is directly proportional to the intensity of light falling
on the photodiodes. For 100 lux of input fluorescent light, the
ISL29000 has an output current of 6.5µA.
The resistor output, RLOAD, determines the voltage transfer
function of the device. The device converts light into current
then RLOAD converts the output current to an output voltage.
RLOAD can range from 10Ω to 10MΩ depending on the input
lux levels. The table below lists RLOAD values to maximize
output swing for typical lux range levels. A careful balance of
dynamic swing and fast response has to be considered
when choosing RLOAD. For faster response, choose a
smaller value RLOAD to shunt stray capacitances that may
slow down response time. For maximum dynamic range or
swing, choose a higher value RLOAD. Although finite, the
output impedance of the device is considerably large.
Hence, the light-to-current conversion deviation because of
resistor loading is infinitesimal. The recommended maximum
RLOAD is 10MΩ.
The ISL29000 is housed in an ultra-compact surface mount
clear plastic package.
Light-to-Current and Voltage Conversion
The ISL29000 has a responsiveness that is directly
proportional to the intensity of light intercepted by the
photodiodes. Although the conversion rate varies depending
on the light sources (fluorescent light, incandescent light or
direct sunlight), in general for a fluorescent light, the
light-to-current conversion is:
61μA
I OUT = ⎛ ------------------------⎞ × L INPUT
⎝ 1000Lux⎠
(EQ. 1)
Here, IOUT is the output current in µA, and LINPUT is the
input light in lux.
4
Although the device saturates at 10,000 lux (IOUT = 600µA),
the output current must never exceed 6mA. The voltage
output compliance of the device is 300mV below the supply.
The output current stops ramping when the output voltage
reaches voltage compliance.
FN6117.6
September 2, 2008
ISL29000
TABLE 1. VDD = 5V, MAXIMUM OUTPUT VOLTAGE = 4.7V
Next, the value of R2 can be calculated based on the
maximum output current coming from the ISL29000 under
the application's maximum light exposure. Suppose the
current has been determined to be about 125µA. Thus, R2
can be calculated approximately using Equations 5 and 6:
ILLUMINATION RANGE
(LUX)
RLOAD
(kΩ)
CURRENT OUT
(µA)
0 to 10
7830
0 to 0.6
0 to 200
392
0 to 12
0 to 500
157
0 to 30
0 to 1,000
80
0 to 60
and
0 to 10,000
8.00
0 to 600
R 1 = 11 × R 2 = 110kΩ
Application Examples
The following examples present from fully automatic to fully
manual override implementations. These guidelines are
applicable to a wide variety of potential light control
applications. The ISL29000 can be used to control the
brightness input of CCFL inverters. Likewise it can interface
well with LED drivers. In each specific application, it is
important to recognize the target environment and its
ambient light conditions. The mechanical mounting of the
sensor, light aperture hole size and use of a light pipe or
bezel are critical in determining the response of the
ISL29000 for a given exposure of light.
The example in Figure 9 shows a fully automatic dimming
solution with no user interaction. Choose R1 and R2 values
for any desired minimum brightness and slope. Choose C1
to adjust response time and to filter 50/60Hz room lighting.
For example, suppose you wish to generate an output
voltage from 0.25V to 1.25V to drive the input of an LED
driver controller. The 0.25V represents the minimum LED
brightness and 1.25V represents the maximum. The 1st step
would be to determine the ratio of R1 and R2:
3.0V
R 1 = R 2 × ⎛ ---------------- – 1⎞ = 11 × R 2
⎝ 0.25V
⎠
3V TO 5V
SUPPLY VOLTAGE
(EQ. 4)
1.25V
R 2 = ⎛ ------------------⎞ = 10kΩ
⎝ 125μA⎠
(EQ. 5)
(EQ. 6)
In Figure 10, user adjustable bias control has been added to
allow control over the minimum and maximum output
voltage. This allows the user to adjust the output brightness
to personal preference over a limit range via the 3V PWM
control.
3V TO 5V
SUPPLY VOLTAGE
3V PWM CONTROL
VDO
R2
110k
ISL29000
EN
TO INVERTER BRIGHTNESS
INPUT OR LED DRIVER
CONTROLLER
OUT
R1
10k
GND
C1
25µF
FIGURE 10. AUTOMATIC DIMMING SOLUTION WITH
ADJUSTABLE BIAS CONTROL
Figure 11 shows how a fully manual override can be quickly
added by using the EN pin.
3V TO 5V
SUPPLY VOLTAGE
3V DC VOLTAGE
3V PWM CONTROL
VDO
VDO
R2
110k
ISL29000
EN
TO INVERTER BRIGHTNESS
INPUT OR LED DRIVER
CONTROLLER
OUT
GND
R1
10k
ENABLE/
DISABLE
CONTROL
R2
110k TO INVERTER
BRIGHTNESS
INPUT OR LED
DRIVER
CONTROLLER
ISL29000
EN
OUT
C1
25µF
GND
R1
10k
C1
25µF
FIGURE 9. AUTOMATIC DIMMING SOLUTION
FIGURE 11. AUTOMATIC DIMMING SOLUTION WITH
ADJUSTABLE BIAS CONTROL AND MANUAL
OVERRIDE
5
FN6117.6
September 2, 2008
ISL29000
Short Circuit Current Limit
The ISL29000 does not limit the output short circuit current.
If the output is directly shorted to the ground continuously,
the output current could easily increase for a strong input
light such that the device may be damaged. Maximum
reliability is maintained if the output continuous current never
exceeds 6mA by adding a load resistor at the output. This
limit is set by the design of the internal metal interconnects.
Suggested PCB Footprint
Footprint pads should be a nominal 1-to-1 correspondence
with package pads. The large, exposed central die-mounting
paddle in the center of the package requires neither thermal
nor electrical connections to PCB, and such connections
should be avoided.
Power Supply Bypassing and Printed Circuit
Board Layout
The ISL29000 is relatively insensitive to the printed circuit
board layout due to its low speed operation. Nevertheless,
good printed circuit board layout is necessary for optimum
performance. Ground plane construction is highly
recommended, lead length should be as short as possible
and the power supply pins must be well bypassed to reduce
the risk of oscillation. For normal single supply operation,
where the GND pin is connected to ground, a 0.1µF ceramic
capacitor should be placed from VCC pin to GND pin. A
4.7µF tantalum capacitor should then be connected in
parallel, placed close to the device.
For additional products, see www.intersil.com/en/products.html
Intersil products are manufactured, assembled and tested utilizing ISO9000 quality systems as noted
in the quality certifications found at www.intersil.com/en/support/qualandreliability.html
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time
without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be
accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
6
FN6117.6
September 2, 2008
ISL29000
Package Outline Drawing
L5.2x2.1
5 LEAD OPTICAL DUAL FLAT NO-LEAD PLASTIC PACKAGE
Rev 1, 05/08
2.10
6
PIN #1 INDEX AREA
A
B
6
PIN 1
INDEX AREA
1
5
1
2.00
1.35
1.30 REF
2
0.65
0.30±0.05 4
(4X)
3
0.10
0.65
0.10 M C A B
5X 0 . 35 ± 0 . 05
TOP VIEW
BOTTOM VIEW
(0.65)
SEE DETAIL "X"
0.10 C
0 . 7 ± 0 . 05
C
( 5X 0 . 30 )
(0.65)
BASE PLANE
(1.35)
SEATING PLANE
0.08 C
SIDE VIEW
( 5X 0 . 55 )
C
0 . 2 REF
5
(1.95)
0 . 00 MIN.
0 . 05 MAX.
DETAIL "X"
TYPICAL RECOMMENDED LAND PATTERN
NOTES:
1.
Dimensions are in millimeters.
Dimensions in ( ) for Reference Only.
2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994.
3.
Unless otherwise specified, tolerance : Decimal ± 0.05
4.
Dimension b applies to the metallized terminal and is measured
between 0.15mm and 0.30mm from the terminal tip.
5. Tiebar shown (if present) is a non-functional feature.
6.
7
The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 identifier may be
either a mold or mark feature.
FN6117.6
September 2, 2008