LP3936SL National Semiconductor, LP3936SL Datasheet - Page 12

• Manufacturer Part Number: LP3936SL
• Manufacturer: National Semiconductor

Specifications of LP3936SL

• Operating Supply Voltage (typ): 3.3/5V
• Number Of Segments: 6
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Package Type: LAM CSP
• Pin Count: 32
• Mounting: Surface Mount
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 6V
• Lead Free Status / Rohs Status: Compliant

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V
DNL
GE
PSS
f(conv)
t
I
I
R
STARTUP
AIN
AREF
IN RANGE
AREF
A/D Converter for Ambient Light Measurement
Electrical Characteristics
Symbol
ADC output AIN[7:0] can be read from address 0CH after startup time. Overflow bit can be read from bit D7 in address 0BH. The
overflow bit indicates that input voltage exceeds the input voltage range of the ADC. The ADC output value in this case is FFH.
When averaging is on, the overflow is high, if any of the 64 conversion results in the averaging period overflows. Thus the
averaged result may be considerably below maximum and the overflow can still be high, if the input signal is noisy.
Examples for optical sensor are photodiode SHF2400 and phototransistor SFH3410 from Osram or BSC 3216 G1 optical sensor
from TDK.
ADC can be used for temperature measurement with a thermistor. It enables temperature compensated LED driving.
If ADC is not used, it should be disabled by writing en_ambadc bit low. AIN and AREF pins can be left unconnected
Input Voltage
Differential Non-Linearity
Gain Error
Power Supply Sensitivity
Conversion Rate
Startup Time
Input Current
Maximum Output Current
AREF Output Resistance
Parameter
AD Output: 00h
AD Output: FFh
3.1V ≤ V
Without Averaging
With Averaging
(64 samples)
1.23
AREF Output Current Sink
<
AIN
DD
≤ 4.2V
12
Conditions
<
2.6V
–1.5
Min
−5
±
±
1.23
2.46
Typ
217
100
200
110
3.4
±
1/2
0.1
1
20081416
Max
+1.5
+5
Units
LSB
LSB
LSB
ms
Hz
Hz
µA
µA
Ω
V
V