A8435EESTR-T Allegro Microsystems Inc, A8435EESTR-T Datasheet - Page 5

• Manufacturer Part Number: A8435EESTR-T
• Description: IC,Laser Diode/LED Driver,LLCC,16PIN,PLASTIC
• Manufacturer: Allegro Microsystems Inc
• Type: Backlight, White LED (Serial Interface)r

Specifications of A8435EESTR-T

• Topology: PWM, Switched Capacitor (Charge Pump)
• Number Of Outputs: 4
• Internal Driver: Yes
• Type - Primary: Backlight, Flash/Torch
• Type - Secondary: White LED
• Frequency: 1MHz
• Voltage - Supply: 2.7 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 16-WFQFN Exposed Pad
• Operating Temperature: -40°C ~ 85°C
• Current - Output / Channel: 30mA
• Internal Switch(s): Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Efficiency: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 620-1124-2

A8435
ELECTRICAL CHARACTERISTICS
V
Input Voltage Range
Undervoltage Lockout Threshold
UVLO Hysteresis Window
Quiescent Current
Soft-Start Completion Time
ISET Bias Voltage
ISET Leakage in Shutdown
ISET Current Range
ISET to LEDx Current Ratio
I
LED Current Matching
Regulation Voltage at LEDx (1.5×)
Open Loop Output Resistance
1× to 1.5× Mode Transition Voltage at LEDx
Transition to Dropout Voltage Difference
LED Leakage in Shutdown
Oscillator Frequency
Output Overvoltage Protection
CTRL, EN1, EN2 Input High Logic Threshold
CTRL, EN1, EN2 Input Low Logic Threshold
Input High Current
Input Low Current
EN1 Pulse Low Time
EN1 Pulse High Time
Initial EN1 Pulse High Time
Shutdown Delay
Thermal-Shutdown Threshold
1
2
3
than 80 mV).
4
5
6
7
LED
Specifications guaranteed by design over operating temperature range, –40°C to 85°C.
LED current matching is defined as (I
The Open Loop Output Resistance for 1.5× mode is measured with one of the LEDx pins tied to ground or open (thus its voltage is always less
Dropout Voltage, V
Guaranteed by design.
EN2 is not used when CTRL is tied to ground.
Applies only when CTRL is tied to ground. See figure 3 in Application Information section.
IN
= V
Accuracy
EN1
= V
Characteristics
EN2
7
Dropout
= 3.6 V, C
7
7
2
, is defined as the LEDx-to-GND voltage at which I
7
3
5
1
= C
2
LEDX
= 1 μF, T
4
1
– I
6
6
LED(AVG)
A
I
V
Symbol
V
LEDx
V
V
UVLOHYS
= –40 to 85°C, typical values at T
V
ISETBIAS
T
V
ISETLKG
t
t
E
∆I
R
LEDLKG
V
V
I
∆V
HI(Init)
SHDN
SHDN
High Efficiency Charge Pump White LED Driver
V
UVLO
ISET
f
V
t
Trans
V
t
I
t
ILED
osc
OVP
I
I
SS
LED
OUT
LO
LED
IH
HI
Q
IL
) / I
/ I
IN
IH
IL
dr
ISET
LED(AVG)
V
Switching, T
EN1 = EN2 = GND, T
I
CTRL = open or HIGH
I
CTRL = LOW
EN1 = EN2 = VIN, R
V
EN1 = EN2 = VIN
1× mode: [(V
1.5× mode: [(1.5 × V
V
Measured as V
EN1 = EN2 = GND, V
Open circuit at any LED that is programmed to be
in the ON state
V
V
First EN1 pulse after shutdown
Falling edge of EN1 pulse
20°C hysteresis
ISET
ISET
IN
IN
LEDx
IH
IL
= GND
= V
.
falling, V
=3.6 V, I
= 60 μA,
= 60 μA,
Falling
IN
A
LED
UVLOHYS
IN
= 25°C
Trans
– V
LEDx
Test Conditions
= 30 mA per LED
OUT
– V
SET
IN
= 35 mV
drops 10% below the value of I
A
IN
) / I
– V
= 25°C
Dropout
= 5.5 V, T
EN1 = EN2 = VIN
EN1 = VIN, EN2 = GND
EN1 = GND, EN2 = VIN
Full brightness
= 4.3 kΩ
OUT
OUT
]
A
) / I
= 25°C (unless otherwise noted)
OUT
A
= 25°C
]
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
LEDX
Min.
2.25
0.56
190
105
100
2.7
1.6
0.5
0.5
40
51
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
at V
LEDX
Typ.
2.45
0.01
±0.9
±0.5
0.01
5.74
219
121
200
150
100
165
2.8
0.1
0.6
1.1
3.6
35
60
60
–
2
–
1
–
–
–
–
–
–
–
2
= 200 mV.
Max.
2.60
0.64
140
245
137
500
5.5
0.4
69
–
4
1
–
1
–
–
–
–
–
–
–
–
1
–
–
–
1
1
–
–
3
–
Units
MHz
A/A
A/A
A/A
A/A
mV
mA
mV
mV
mV
ms
ms
μA
μA
μA
μA
μA
μA
μs
μs
μs
°C
%
%
Ω
Ω
V
V
V
V
V
V
4