CM9321 Datasheet, PDF (4/11 Pages) California Micro Devices Corp – Asymmetrical High Efficiency Three Channel Boost LED/OLED Driver

PRELIMINARY
CM9321
Specifications (cont’d)
ELECTRICAL OPERATING CHARACTERISTICS ^{(SEE NOTE 1)}
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX UNITS
Eff
Efficiency
Standard Load (Note 3)
85
%
I_SW
Switch Peak Current
Standard Load (Note 3)
0.65
A
P_IN
Input Power
I_{LED 1,2} = 20mA,
4WLED+OLED+2W
950
mW
Control
I_{LED acc}
Channel Current Matching 1% R_SET Accuracy, Each Channel
3
%
(Note 5)
I_LEDR
LED Current Ripple
Standard Load (Note 3)
0.2
mApp
I_LEDNL
No-Load Mode (Note 5) All Channels
0
0.6
mA
fs
Switching Frequency
V_IN = 2.7V to 6.0V
0.8
1.0
1.2 MHz
V_IN = 3.6V; C_IN = 10μF, C_OUT = 1μF, C_OLED = 1μF, L₁ = 4.7μH, non-interleave mode (Note 7), T_A = 25°C (unless otherwise
specified)
I_LED
LED Current
V_IN = 3.0V to 6.0V, R_SET(kΩ)
2
---7---3---0---
I_MAX
mA
R_SET
P_IN
Input Power
I_{LED 1,2,3} = 20mA,
4WLED+OLED+2W
990
mW
Note 1: I_LED is the average PWM current through the LED string with internal 2/3 duty cycle and a 6 ms period. The following for-
mula must be used to calculate the LED current:
ILED(mA)
=
--------⁴---⁵--⁰---------
RSET_(kΩ)
Note 2: For lower LED forward voltage the number of LEDs can be increased up to the maximum output voltage limit.
Note 3: Standard Load is a 4 series x 2 parallel WLEDS configured for I_setLED = 20 mA each channel (R_SET1 = R_SET3 = 22 kΩ) and
one OLED channel (CH2) which drives V_OLED=12V and I_OLED=20mA.
Note 4: V_VSET2, the voltage on VSET2 pin should be maintained in the 0.4V - 1.0V range. The following formulae are related to
OLED channel settings:
V_OLED
=
V_OUT – V_LED
,
V_OLED
=
20 × V_SET2
,
V_VSET2
=
-------------R----^S---^E---^T---²---²-------------
R_SET21 + R_SET22
×
V_REF
Note 5: [ILED(set) - ILED(effective)]/ILED(set) for each channel.
Note 6: A ILED value below 0.6 mA for each channel set the circuit in no-load mode; all channels and MOSFET switch are in shut-
down and DC circuit current consumption is limited to 1 mA (see quiescent current).
Note 7: For non-interleave mode, all parameters have the same min/typ/max interleave mode values, unless otherwise specified.
© 2006 California Micro Devices Corp. All rights reserved.
4 490 N. McCarthy Blvd., Milpitas, CA 95035-5112 l Tel: [phone] l Fax: [phone] l www.cmd.com
04/26/06