Preliminary
5+2 Channel DC/DC Converters for DV
RT9992
General Description
This is a 5+2CH integrated PMIC for DV a pplication. There
are 5 DC/DC converters : one synchronous step-up, one
selectable synchronous step-up/step-down, two
synchronous step-downs, and one WLED driver in either
asynchronous ste p-up or current source mode, selectable
by VOUT6 initial voltage. In addition, there are 2 LDO
regulators : one RTC LDO and one generic LDO. The
generic LDO can choose internal feedba ck loop for fixed
output 2.5V or external feedback loop for customized
output voltage. Both low voltage synchronous step-up
converters are with load disconnect function. All power
MOSFETs and compensation networks are integrated.
There is a power good indicator to monitor FB2, FB3, and
FB4 voltage status. CH1 to CH5 enabling ca n be controlled
flexibly : enabled independently or in preset sequences.
Ordering Information
RT9992
Package Type
QW : WQFN-32L 4x4 (W-Type)
Operating Temperature Range
G : Green (Halogen Free with Commer cial Standard)
Z : Cu wire and Green (Halogen Free
with Commer-cial Standard)
Note :
Richtek Green products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Pin Configurations
(TOP VIEW)
Features
zz
All Power MOSFETs Integrated
z
zz
zz
z 5 Channels with Internal Compensation
zz
zz
z Flexible Enabling Control
zz
``
` Enabled Independently or in Preset Power On/
``
Off Sequences
zz
z CH2 Synchronous Converter in Step-Up or Step-
zz
Down Mode Selectable by SEL Pin
zz
z Synchronous Step-Down DC/DC Converter
zz
``
` Up to 95% Efficiency
``
``
` 100% (max) Duty Cycle
``
zz
z Synchronous Step-Up DC/DC Converter
zz
``
` Adjustable Output Voltage
``
``
` Up to 95% Efficiency
``
zz
z Asynchronous Step-Up Converter to Drive WLED,
zz
Selectable Between Step-Up or Current Source
``
` LED Open Protection (OVP6) in Step-Up Mode
``
``
` PWM Dimming Control
``
zz
z Load Disconnect Function for CH1 and CH2
zz
Synchronous Step-Up Converter
zz
z Fixed 2MHz Switching Frequency for CH1, CH2,
zz
CH3, and CH4
zz
z Fixed 1MHz Switching Frequency for CH6
zz
zz
z Generic LDO (CH5)
zz
``
` Output Voltage : Fixed 2.5V or Set by External
``
Feedback Network, Determined by FB5 Initial
Voltage
zz
z RTC LDO : Fixed Output Voltage 3.1V
zz
zz
z Power Good Indicator to Monitor Output Voltage
zz
Status of CH2, CH3, and CH4
zz
z 32-Lead Package
zz
zz
z RoHS Compliant and Halogen Free
zz
Applications
LX1
PVDD1
BAT
32
1
FB1
PGOOD
VOUT5
PVDD5
2
3
FB5
4
5
6
EN5
7
SEQ FB3
8
LX2 FB4
9
PVDD2 EN1
GND
10 11 12 13
EN2
VIN2
FB2
27
33
14
SEL
PVDD4 PVDD6
25
152616
LX4 VDDM
EN4 FB6
24
23
22
21
20
19
18
17
VOUT6
LX6
EN6
PVDD3
LX3
EN3
RTCPWR
31 30 29 28
WQFN-32L 4x4
DS9992-P04 May 2010 www.richtek.com
z CMOS D V
z Gaming
Marking Information
ES= : Product Code
ES=YM
DNN
YMDNN : Date Code
1
RT9992
Typical Application Circuit
For 2AA :
R10
BAT
R11
R12
100k
L6
10µH
V
EN1234
C15
0.1µF
C16
1µF
C18
4.7pF
V
V
V
V
C1
1µF
C2
1µF
BAT
BAT
EN5
BAT
5V
D4
1µF
3V
3.3V
V
BAT
R13
10
Chip Enable
3.1V
3.3V
C17
1µF
C14
1µF
D1
D2
D3
V
909k
180k
2
PGOOD
23
LX6
24
VOUT6
25
FB6
29
BAT
26
VDDM
32
EN1
11
EN2
19
EN3
16
EN4
6
EN5
22
EN6
7
SEQ
27
PVDD6
13
SEL
28
RTCPWR
5
PVDD5
4
VOUT5
3
FB5
Preliminary
RT9992
LX1
PVDD1
FB1
PVDD2
FB2
VIN2
LX2
PVDD3
LX3
FB3
PVDD4
LX4
FB4
GND
L1
2.2µH
31
C5
C3
10µF
R3
470k
R4
150k
C7
10µF
C8
10µF
C9
10µF
C11
10µF
C12
10µF
30
10µF x 2
1
9
12
10
L2
2.2µH
8
21
L3
2.2µH
20
18
14
L4
2.2µH
15
17
33 (Exposed Pad)
R1
470k
R2
88.7k
C6
10µF*2
C18
4.7pF
R5
470k
R6
374k
R7
187k
R8
374k
C4
4.7pF
C10
33pF
C13
82pF
V
BAT
5V
3.3V
V
BAT
5V/3.3V
1.8V
V
BAT
1.2V
For above circuit, the power sequence is CH1 CH3 CH4 CH2, while CH5 remains independent.
→ → →
For other power sequence combinations, refer to the power on/ff sequence section in a pplication information.
DS9992-P04 May 2010www.richtek.com
2
For Li+ :
3.3V
V
BAT
V
BAT
C1
1µF
5V
Chip Enable
V
BAT
3.1V
0.1µF
3.3V
2.5V
1µF
C15
C16
1µF
C17
1µF
R10
100k
D5
C2
V
EN1
V
EN2
V
EN3
V
EN4
V
EN5
2
PGOOD
13
SEL
29
BAT
27
PVDD6
25
FB6
26
VDDM
32
EN1
11
EN2
19
EN3
14
EN4
6
EN5
22
EN6
23
LX6
24
VOUT6
7
SEQ
3
FB5
28
RTCPWR
5
PVDD5
4
VOUT5
Preliminary
RT9992
LX1
PVDD1
FB1
PVDD2
LX2
FB2
VIN2
PVDD3
LX3
FB3
PVDD4
LX4
FB4
GND
L1
2.2µH
31
C3
10µF
C7
10µF
C9
10µF
C12
10µF
30
10µF x 2
1
9
L2
2.2µH
8
12
R9
470k
10
21
L3
2.2µH
20
18
14
L4
2.2µH
15
17
33 (Exposed Pad)
C5
C6
10µF
C8
10µF
C11
10µF
R1
470k
R2
88.7k
R3
470k
R4
150k
R5
470k
R6
374k
R7
187k
R8
374k
C4
4.7pF
C18
10pF
C10
33pF
C13
82pF
RT9992
V
BAT
5V
V
BAT
3.3V
V
BAT
1.8V
V
BAT
1.2V
For above circuit, all channels are independently ena ble/disable.
For other power sequence combinations, refer to the power on/ff sequence section in a pplication information.
DS9992-P04 May 2010 www.richtek.com
3
RT9992
Table 1. Recommended Components for the Typical Application Circuit
Channel CH3
Calculation V
V
(V) 2.5 1.8 1.5 1.3 1.2 1
OUT
L3 (μH) 2.2 2.2 2.2 2.2 2.2 2.2
R5 (kΩ) 768 470 330 237 187 23.2
R6 (kΩ) 360 374 374 374 374 93.1
C9 (μF) 10 10 10 10 10 10
C10 (pF) 22 33 47 68 82 47
Preliminary
OUT_CH3
= (1+R5/R6) x 0.8V
Channel CH4
Calculation V
V
(V) 2.5 1.8 1.5 1.3 1.2 1
OUT
L4 (μH) 2.2 2.2 2.2 2.2 2.2 2.2
R7 (kΩ) 768 470 330 237 187 23.2
R8 (kΩ) 360 374 374 374 374 93.1
C12 (μF) 10 10 10 10 10 10
C13 (pF) 22 33 47 68 82 47
OUT_CH4
= (1+R7/R8) x 0.8V
Where C9, C12 are C
C10, C13 are feedforward ca p between output and FB
R5, R7 are the feedback resistor between output and FB
R6, R8 are the feedback resistor between GND and FB
OUT
,
DS9992-P04 May 2010www.richtek.com
4
Preliminary
Functional Pin Description
Pi n N o . Pi n N a m e Pi n Fun cti on
1 FB1 Feedback In put Pin of CH1. High impedance in shutdown.
2 PG OOD Power Good Indicator Output Pin (Open Drain).
3 FB5 Feedback In put Pin of CH5. High Impedance in Shutdow n.
4 VO UT5 Output Pin f or CH5. High Impedance in Shutdown.
5 PVD D5 Po we r Input Pin of CH5.
6 EN5 E nab le Pin of CH5.
7 SEQ
8 LX2 Switch Node of CH2. Hig h Impedance in Shutdown .
9 PVDD2
10 VIN2 Powe r Input N ode of CH2 in Step- Up.
11 EN2 Enable Pin of CH2 or Enable Pi n of Preset On/Off Seq uence.
12 FB2 Fee dback In put Pin of CH2. High Impedance in Shut dow n.
13 SEL
14 PVD D4 Po we r Input Pin of CH4.
15 LX4 Switch Node of CH4. Hig h Impedance in Shu td own.
16 EN4 Enable Pin of CH4 or Select which P re set On/O f f Sequenc e.
17 FB4 Fee dback In put Pin of CH4. High Impedance in Shut dow n.
18 FB3 Fee dback In put Pin of CH3. High Impedance in Shut dow n.
19 EN3 Enable Pin of CH3 or Select which P re set On/O f f Sequenc e.
20 LX3 Switch Node of CH3. Hig h Impedance in Shu td own.
21 PVD D3 Po we r Input Pin of CH3.
22 EN6 Enable Pin of CH6 and PWM Di mming Input Signal Pin.
23 LX6 Switch Node of CH6 in St ep- Up Mode. High Impedance in Shutdown.
24 VOUT6
25 FB6
26 VDDM
27 PVD D6 Po we r Input Pin of CH6 NMO S D river.
28 RTCPWR RTC Power Output Pin.
29 BAT Battery Power Input Pin and CH1 Step-Up Power Input Node.
30 PVD D1 Po we r Output Pin of CH1.
31 LX1 Switch Node of CH1. Hig h Impedance in Shu td own.
32 EN1 Enable Pin of CH 1.
33
(Exposed pad)
GND
SEQ = H to use preset power on/off sequence. SEQ = L to independently
enable CH1 to 5. Logic state can’t be chang ed dur ing opera tion.
Power Input Pin of CH2 in Step-Down or Power Output Pin of CH2 in
Step-Up.
Select Pin to Define CH2 in Step-Down (SEL = H) or Step-Up (SEL = L)
Mode. Logic state can’t be chang ed during oper at io n.
Sense Pi n fo r CH6 Output V o l tag e in Step- U p M ode and CH6 Mod e Sel ect ion
Pin.
Feedback Input Pin of CH6 in Step-Up Mode or Current Sink Pin of CH6 in
Current Source Mode.
Internal Control Circuit Power Pin. That must connect to a bypass capacitor
for better noise r ejection.
Ground. The exposed pa d must be soldered to a larg e PC B and connected to
GND for maxi mum po wer dissipation.
RT9992
DS9992-P04 May 2010 www.richtek.com
5
RT9992
Function Block Diagram
Preliminary
BATPVDD6 VDDM
PGOOD
LX6
VOUT6
FB6
EN6
EN1
EN2
EN3
EN4
EN5
SEL
SEQ
FB2
VDDM
Power
Good
FB3 FB4
30mA
CH6
Step-Up
+
Current Source
+
PWM Dimming
0.25V
REF
Power ON/Off
Sequence Control
Logic Block
-
VDDM
+
VDDM
VDDI
UVLO
VDDI
VDDM
CH1
C-Mode
Step-Up
VDDM
CH2
C-Mode
Step-Up
or
Step-Down
VDDM
PVDD1
Body
Diode
Control
-
0.8V
+
REF
Body
Diode
Control
-
0.8V
+
REF
BAT
LX1
FB1
PVDD2
VIN2
LX2
FB2
PVDD3
RTCPWR
PVDD5
VOUT5
int
ext
FB5
CH5
SEL
GND
RTC_LDO
w/Body Diode Control
CH5
LDO
-
0.5V
REF
+
CH3
C-Mode
Step-Down
VDDM
CH4
C-Mode
Step-Down
LX3
-
0.8V
+
REF
-
0.8V
+
REF
FB3
PVDD4
LX4
FB4
DS9992-P04 May 2010www.richtek.com
6
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