Datasheet

ADM8845
Rev. C | Page 3 of 20
SPECIFICATIONS
V
CC
= 2.6 V to 5.5 V; T
A
= −40°C to +85°C, unless otherwise noted; C1, C2 = 1.0 µF; C3 = 2.2 µF; C4 = 4.7 µF.
Table 1.
Parameter Min Typ Max Unit Test Conditions
INPUT VOLTAGE, V
CC
2.6 5.5 V
SUPPLY CURRENT, I
CC
2.6 5 mA All six LEDs disabled, V
CC
= 3.3 V, R
SET
= 7.08 kΩ
CTRL1 = 1, CRTL2 = 1
SHUTDOWN CURRENT 5 µA
CHARGE PUMP FREQUENCY 1.5 MHz
CHARGE PUMP MODE THRESHOLDS
1.5× to 2× 3.33 V
Accuracy 4 %
2× to 1.5× 3.36 V
Accuracy 4 %
Hysteresis 40 mV
1× to 1.5× 4.77 V
Accuracy 4 %
1.5× to 1× 4.81 V
Accuracy 4 %
Hysteresis 40 mV
I
SET
PIN
LED: LED Matching −1 +1 % I
LED
= 20 mA, V
FB
=0.4 V
LED: I
SET
Accuracy −1 +1 % I
LED
= 20 mA, R
SET
= 7.08 kΩ, V
FB
= 0.4 V, V
CC
= 3.6 V, T
A
= 25°C
I
SET
Pin Voltage 1.18 V
I
LED
to I
SET
Ratio 120
MIN COMPLIANCE ON FBx PIN 0.2 0.3 V I
SET
= 20 mA
Charge Pump Output Resistance 1.2 1.8 Ω 1× mode
3.5 5.1 Ω 1.5× mode
8.0 14 Ω 2× mode
LED Current 30 mA Guaranteed by design. Not 100% production tested. See Figure 21.
PWM 0.1 200 kHz
DIGITAL INPUTS
Input High 0.5 V
CC
V
Input Low 0.3 V
CC
V
Input Leakage Current 1 µA
CHARGE PUMP POWER EFFICIENCY 88 % CTRL1 = 1, CRTL2 = 1, V
CC
= 3.4 V, V
FB
= 0.2 V, I
FB
= 20 mA
V
OUT
RIPPLE 30 m V V
CC
= 3.6 V, I
LED
= 20 mA, all six LEDs enabled