XRP6840EVB Exar Corporation, XRP6840EVB Datasheet - Page 10

• Manufacturer Part Number: XRP6840EVB
• Description: Supercapacitor Flash LED Driver Eval. Board
• Manufacturer: Exar Corporation

Specifications of XRP6840EVB

• Core Chip: XRP6840
• Output Current: 4.3A
• No. Of Outputs: 1
• Tool / Board Applications: Lighting-LED, High Bright LED, LED Driver, Flourescent, Backlighting
• Current - Output / Channel: 4.3A, 3x 1.5A
• Outputs And Type: 4, Non-Isolated
• Features: Supercapacitor Flash
• Voltage - Input: 2.7 ~ 5.5 V
• Utilized Ic / Part: XRP6840
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 1016-1337

APPLICATION INFORMATION
I
R
The XRP6840 has five serially programmable
data registers via the I²C interface. These
registers can be reset to ‘0’ through power on
reset or setting RESET_N, pin 6, to ‘0’. The
first register is for Device Address as shown in
Figure 3; it is activated by ‘28’ HEX (7-bit
format).
contains the control word for programming
operating modes, shutdown control, charge
pump modes and flash timeout. The third
register, STATUS2, contains the flash voltage
level, read back of the Flash Ready, and fault
conditions UVLO and over temperature. The
fourth register, LEDFLASH, controls individual
LED channels and current level in Flash Mode.
The
individual LED channels and current level in
Torch Mode.
* Not used for XRP6840B
STATUS1 Register Bits B7, B6, B4 and B3
© 2009 Exar Corporation
2
STATUS1 Register
EGISTERS
LEDTORCH
B7
LEDFLASH
C S
Register
STATUS1
STATUS2
0
0
0
0
1
1
1
1
1
1
1
1
Address
Table 2: STATUS1 Register Operation Modes
ERIAL
fifth
B6
Table 1: XRP6840 I
1
1
1
1
0
0
0
0
1
1
1
1
The
I
B4
register,
Torch
Flash
Mode
Flash
LED1
LED1
B7
0
0
1
1
0
0
1
1
0
0
1
1
NTERFACE
V
0
second
Torch
Flash
Mode
Flash
LED2
LED2
B6
B3
1
V
0
1
0
1
0
1
0
1
0
1
0
1
Control
LED3*
LED3*
Down
Flash
B5
Shut
High Efficiency Torch Mode
1X Torch Mode
1.5X Torch Mode
2X Torch Mode
Auto Gain Torch Mode
1X Torch Mode
1.5X Torch Mode
2X Torch Mode
Auto Gain Flash Mode
1X Flash Mode
1.5X Flash Mode
2X Flash Mode
2
0
V
C Registers Bit Map
LEDTORCH,
register,
Ready
Flash
B4 B3 B2
Gain
D2
D3
1
Operation Mode
UVLO
Fault
Gain
D1
D2
0
Temp
Fault
D0
D1
0
-
STATUS1,
Timeout
4
4
Flash
B1
controls
D0
0
0
.
-
.
3
3
A
A
Timeout
Flash
B0
R/W
0
-
-
S
S
u
u
10/17
p
p
e
e
r
r
STATUS1 Register Bit B5
This bit is used to save or reset the contents
of
LEDTORCH registers for the next I
when RESET_N, pin 6, is ‘1’. If B5 is ‘1’ then
all bits in these registers will be saved.
Otherwise if B5 is ‘0’ then all bits will be reset
to ‘0’.
STATUS1 Register Bits B1 and B0
These two bits program the flash timeout
duration as follows:
Flash Mode Voltage Programming
V
of hysteresis and is programmed through bits
B7, B6 and B5 of STATUS2 register as follows:
Bit B4
RDY bit is available for I
is set to ‘1’ when V
‘0’ otherwise.
Fault mode read-back bits B3, B2
These bits are designed for 2 Fault Mode flags
and are also available for I
3 and 2 are set to ‘1’ when UVLO and over
temperature
shown in Table 1.
LEDFLASH register, bits B7, B6 and B5 are
used to activate the LED outputs channels as
summarized in Table 1; they correspond to
LED
c
c
OUT_LIMIT
STATUS2 Register
LEDFLASH Register
a
a
B1
B7
0
0
1
1
0
0
0
0
1
1
1
1
p
p
1
STATUS1,
, LED
a
a
c
c
B0
B6
i
i
0
1
0
1
0
0
1
1
0
0
1
1
Table 3: Charge Pump Mode Selection
Table 4: Flash Mode V
t
t
in Flash Mode is regulated with 50mV
o
o
2
r
r
and LED
B5
F
F
0
1
0
1
0
1
0
1
l
conditions
l
a
a
s
s
STATUS2,
h
h
OUT
L
L
3
.
E
E
Flash Duration
> V
D
D
2
C read-back. This bit
Bits B4, B3 and B2
OUT_LIMIT
D
D
0.11s
0.22s
0.53s
1.10s
are
OUT_LIMIT
2
Comment
C read-back. Bits
r
r
4.55V
4.70V
4.85V
5.00V
5.15V
5.30V
5.45V
5.60V
i
i
LEDFLASH
v
v
Settings
e
e
X
X
detected,
r
r
2
, and set to
R
R
C command
w
w
P
P
Rev. 1.0.0
i
i
6
6
t
t
h
h
8
8
I
I
4
4
and
2
2
as
0
0
C
C