ADP8861ACPZ-R7 Analog Devices Inc, ADP8861ACPZ-R7 Datasheet - Page 13

• Manufacturer Part Number: ADP8861ACPZ-R7
• Description: Charge Pump Based Backlight Controller
• Manufacturer: Analog Devices Inc
• Series: -r

Specifications of ADP8861ACPZ-R7

• Constant Current: -
• Constant Voltage: -
• Topology: Switched Capacitor (Charge Pump)
• Number Of Outputs: 7
• Internal Driver: Yes
• Type - Primary: Backlight, LED Blinker
• Type - Secondary: RGB, White LED
• Frequency: 800kHz ~ 1.32MHz
• Voltage - Supply: 2.5 V ~ 5.5 V
• Voltage - Output: 4.3 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 20-WFQFN Exposed Pad, CSP
• Operating Temperature: -40°C ~ 85°C
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Soft Start Feature
At startup (either from UVLO activation or fault/standby
recovery), the output is first charged by I
until it reaches about 92% of V
the inrush current that is otherwise present when the output
capacitance is initially charged to V
reached, the controller enters G = 1× mode. If the output
voltage is not sufficient, then the automatic gain selection
determines the optimal point as defined in the Automatic Gain
Selection section.
OPERATING MODES
There are four different operating modes: active, standby,
shutdown, and reset.
Active Mode
In active mode, all circuits are powered up and in a fully
operational state. This mode is entered when Bit nSTBY (in
Register MDCR) is set to 1.
Standby Mode
Standby mode disables all circuitry except for the I
Current consumption is reduced to less than 1 μA. This mode is
entered when the nSTBY bit is set to 0 or when the nRST pin is
held low for more than 100 μs (maximum). When standby is
exited, a soft start sequence is performed.
STANDBY
nRST
V
OUT
V
IN
SHUTDOWN
V
IN
IN
. This soft start feature reduces
IN
. When this point is
V
IN
~100µs DELAY BETWEEN POWER-UP AND
WHEN I
CROSSES ~2.05V AND TRIGGERS POWER-ON RESET
SS
BIT nSTBY IN REGISTER
MDCR GOES LOW
~3.75mA CHARGES
V
(3.75 mA typical)
OUT
2
C COMMANDS CAN BE RECEIVED
SOFT START
TO V
IN
2
25µs TO 100µs NOISE FILTER
C receivers.
LEVEL
Figure 27. Typical Timing Diagram
Rev. A | Page 13 of 40
10µs 100µs
1×
1.5×
Shutdown Mode
Shutdown mode disables all circuitry, including the I
Shutdown occurs when V
When V
reset and the part is placed into standby mode.
Reset Mode
In reset mode, all registers are set to their default values and
the part is placed into standby. There are two ways to reset the
part: by power-on reset (POR) or using the nRST pin. POR is
activated any time that the part exits shutdown mode. After
a POR sequence is complete, the part automatically enters
standby mode.
After startup, the part can be reset by pulling the nRST pin low.
As long as the nRST pin is low, the part is held in a standby state
but no I
at their default values). After releasing the nRST pin, all registers
remain at their default values, and the part remains in standby;
however, the part does accept I
The nRST pin has a 50 μs (typical) noise filter to prevent inad-
vertent activation of the reset function. The nRST pin must be
held low for this entire time to activate reset.
The operating modes function according to the timing diagram
in Figure 27.
2×
GAIN CHANGES OCCUR ONLY WHEN NECESSARY,
BUT HAVE A MIN TIME BEFORE CHANGING
2
IN
C commands are acknowledged (all registers are kept
rises above V
nRST IS LOW, WHICH FORCES STANDBY LOW
AND RESETS ALL I
nRST MUST BE HIGH FOR 20µs (MAX)
BEFORE SENDING I
IN(START)
IN
2
C REGISTERS
is below the undervoltage thresholds.
SOFT START
2
C COMMANDS
2
(2.05 V typical), all registers are
C commands.
ADP8861
2
C receivers.