XRP7714
Quad Channel Digital PWM Step Down Controller
September 2010
Rev. 1.1.4
GENERAL DESCRIPTION
The XRP7714 is a quad-output pulse-width
modulated (PWM) step-down DC-DC controller
with a built-in LDO for standby power and
GPIOs. The device provides a complete power
management solution in one IC and is fully
programmable via an I
2
C serial interface.
Independent Digital Pulse Width Modulator
(DPWM) channels regulate output voltages
and provide all required protection functions
such as current limiting and over-voltage
protection.
Each output voltage can be programmed from
0.9V to 5.1V without the need of an external
voltage divider. The wide range of the
programmable DPWM switching frequency
(from 300 KHz to 1.5 MHz) enables the user to
optimize between efficiency and component
size. Input voltage range is from 4.75V to
25V.
An I
2
C bus interface is provided to
program the IC as well as to communicate
with the host for fault reporting and handling,
power rail parameters monitoring, etc.
The device offers a complete solution including
independently programmable: soft-start, soft-
stop, start-up delay and ramp of each PWM
regulator.
APPLICATIONS
•
Multi Channel Power Supplies
•
Audio-Video Equipments
•
Industrial & Telecom Equipments
•
Processors & DSPs Based Equipments
FEATURES
•
4 x 5A Channel Step Down Controller
−
Programmable Output Voltage 0.9V-5.1V
−
Programmable 1.5MHz DPWM Frequency
−
Integrated FET Drivers
•
4.75V to 5.5V and 5.5V to 25V Input
Voltage Range
•
Up to 6 Reconfigurable GPIO Pins
•
Fully Programmable via I
2
C Interface
•
Independent Digital Pulse Width
Modulator (DPWM) channels
•
Complete Monitoring and Reporting
•
Complete Power Up/Down Sequencing
•
Full On Board Protection
OTP, UVLO, OCP and OVP
•
Built-in 3.3V/5V LDO
•
PowerArchitect™ Design Software
•
Green/Halogen Free 40-pin TQFN
TYPICAL APPLICATION DIAGRAM
VIN: 4.75 TO 25V
VCCA
Vin
C3
GL1
C5
GH1
LX1
C4
D1
C1
GH1
GL1
LX1
Q1
Q2
Vout1
L1
C2
VOUT1
LDO OUT
40
39
38
36
32
37
35
34
33
31
VCCD
Vin
C6
GH2
GL2
LX2
LX2
Q3
Q4
Vout2
L2
VOUT2
PGND1
LDOOUT
PGND2
VCCA
BST1
LX1
VIN1
VIN2
GH1
GL1
C8
1
2
AVDD
DVDD
GPIO0
GPIO1
GPIO2
GPIO3
GL2
LX2
GH2
30
29
28
27
26
25
24
23
22
21
C7
GL2
C9
D2
R1
C10
D3
R2
GH4
C11
ENABLE
LX4
GL4
GH4
C14
C12
VCCD
VCCA
Vin
GPIO0
GPIO1
GPIO2
GPIO3
3
4
5
6
7
8
9
10
GH2
U1
XRP7714
BST2
VCCD
BST4
GH4
LX4
Q5
Q6
Vout4
L3
VOUT4
I2C
SDA
SCL
GPIO4_SDA
GPIO5_SCL
ENABLE
Exposed Pad: DGND
C13
LX4
GL4
PGND4
GL4
ENABLE
PGND3
VOUT1
VOUT2
VOUT3
VOUT4
DGND
Vout3
LX3
Vin
AGND
BST3
GH3
GL3
LX3
VOUT3
L4
C16
D4
Q7
C15
GH3
Q8
GL3
11
12
13
14
15
16
17
18
19
Vout4
Vout3
Vout2
Vout1
GL3
GH3
20
VCCD
C17
LX3
Fig. 1: XRP7714 Application Diagram
Exar Corporation
48720 Kato Road, Fremont CA 94538, USA
www.exar.com
Tel. +1 510 668-7000 – Fax. +1 510 668-7001
XRP7714
Quad Channel Digital PWM Step Down Controller
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation of
the device at these ratings or any other above those
indicated in the operation sections of the specifications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect
reliability.
VCCA, VCCD, LDOOUT, GLx, VOUTx............................ 6V
VDD..................................................................... 2.0V
VIN1, VIN2 ............................................................ 27V
LXx .............................................................. -1V to 27V
LXx ............................................................. -5V to -1V
1
Logic Inputs, GPIOs, SDA, SCL ................................... 6V
BSTx, GHx .................................................... VLXx + 6V
ESD Rating (HBM - Human Body Model) .................... 2kV
Storage Temperature .............................. -65°C to 150°C
Lead Temperature (Soldering, 10 sec) ................... 300°C
Note 1: 200ns Transient
OPERATING RATINGS
Input Voltage Range..................................... 5.5V to 25V
Input Voltage VIN=VCCA ........................... 4.75V to 5.5V
Junction Temperature Range ....................-40°C to 125°C
Thermal Resistance θ
JA
....................................24.3°C/W
ELECTRICAL SPECIFICATIONS
Specifications with standard type are for an Operating Junction Temperature of T
J
= 25°C only; limits applying over the full
Operating Junction Temperature range are denoted by a “•”. Minimum and Maximum limits are guaranteed through test,
design, or statistical correlation. Typical values represent the most likely parametric norm at T
J
= 25°C, and are provided for
reference purposes only. Unless otherwise indicated, VIN
1
= 4.75V to 25V, VIN
2
= 4.75V to 25V.
Quiescent Current
Parameter
VIN Supply Current in STANDBY
VIN Supply Current in
SHUTDOWN
VIN Supply Current
Min.
Typ.
9
Max.
Units
mA
Conditions
LDOOUT enabled (no load)
No switching converter channels enabled
I
2
C communication active
Switching frequency = 400kHz
EN=0V, VIN1≥5.2V, VIN2≤25V
4 channels running,
GH and GH = 1nF load each
VIN=12V, Switching frequency = 300kHz
4 channels running,
GH and GH = 1nF load each
VIN=12V, Switching frequency = 1MHz
180
28
µA
mA
VIN Supply Current
50
mA
Step Down Controllers
Parameter
VOUT Regulation Accuracy
VOUT regulation range
VOUT set point resolution
VOUT set point resolution
VOUT Input Current
VOUT Input Resistance
Min.
-20
-40
0.9
50
100
100
120
nA
kΩ
Typ.
Max.
20
40
5.1
Units
mV
mV
•
•
•
Conditions
0.9V ≤ VOUT ≤ 2.5V
2.6V ≤ VOUT ≤ 5.1V
Programmable range of each channel
2
0.9V ≤ VOUT ≤ 2.5V
2.6V ≤ VOUT ≤ 5.1V
0.9V < VOUT <= 2.5V
2.6V ≤ VOUT ≤ 5.1V
Note 2: Voltages above 5.1V can be obtained by using an external voltage divider.
© 2010 Exar Corporation
2/29
Rev. 1.1.4
XRP7714
Quad Channel Digital PWM Step Down Controller
Low Drop-out Regulator
Parameter
LDOOUT Output Voltage
LDO=LOW
LDOOUT Output Voltage
LDO=HIGH
LDOOUT Short Circuit Current
Limit
Min.
3.15
4.75
110
Typ.
3.3
5.0
Max.
3.45
5.25
220
Units
V
V
mA
•
•
•
Conditions
4.75V≤VIN1≤25V
0mA<I
LDOOUT
<100mA
6.3≤VIN1≤25V
0mA<I
LDOOUT
<100mA
V
LDOOUT
=0V
Auxiliary ADCs
Parameter
Linearity Error Integral
Linearity Error Differential
Input Dynamic Range VIN1
Input Dynamic Range VIN2
-1
4.8
4.8
Min.
Typ.
Max.
2
1
25
25
Units
LSB
LSB
V
V
•
•
Conditions
Isense ADC
Parameter
ADC LSB
Input Dynamic Range
0
Min.
Typ.
5
-320
Max.
Units
mV
mV
Conditions
Referred to the input
PWM Generators and Oscillator
Parameter
Output frequency range
Output Frequency Accuracy
Channel-to-channel phase shift
Minimum On Time
Min.
300
-10
90
40
13
Dead Time Adjustment Step
1.5
CLOCK IN Synchronization
Range
Maximum Duty Cycle
2
ns
Typ.
Max.
1500
10
Units
kHz
%
deg
ns
ns
1nF of gate capacitance
Switching frequency = 300kHz
10% to 90% duty cycle, Frequency
dependant; refer to the graph in
performance characteristic section
Switching frequency = 1.5MHz
10% to 90% duty cycle, Frequency
dependant; refer to the graph in
performance characteristic section
•
•
•
Switching frequency = 300kHz
Switching frequency = 1.5MHz
•
Conditions
Steps defined in the table in the PWM
Switching Frequency Setting section
below
-5
86
78
5
%
%
%
Note 2: The maximum duty cycle represents the maximum duty cycle commanded by the DPWM, is guaranteed by design,
and internally set to ensure proper sampling of the current during the off-time.
© 2010 Exar Corporation
3/29
Rev. 1.1.4
XRP7714
Quad Channel Digital PWM Step Down Controller
Digital Input/Output Pins (GPIO0-GPIO5) and ENABLE
3.3V CMOS logic compatible, 5V tolerant.
Parameter
Enable Pin Threshold
Input Pin Low Level
Input Pin High Level
Input Pin Leakage Current
Input pin Capacitance
Output Pin Low Level
Output Pin High Level
Output Pin High Level (no load)
2.4
3.3
3.6
5
0.4
2.0
10
Min.
1.08
Typ.
1.14
Max.
1.2
0.8
Units
V
V
V
µA
pF
V
V
V
•
•
•
I
SINK
=1mA
I
SOURCE
=1mA
I
SOURCE
=0mA
•
•
•
V
IO
=3.3V
Conditions
Chip Enable rising threshold
I
2
C Specification
Parameter
I C Speed
Input Pin Low Level, V
IL
Input Pin High Level, V
IH
Hysteresis of Schmitt Trigger
Inputs, V
HYS
Output Pin Low Level (open
drain or collector) V
OL
Input Leakage Current
Output Fall Time from V
IHMIN
to
V
ILMAX
Capacitance for each I/O Pin
Note 3: C
b
is the capacitance of one bus in pF
-10
20+0.1C
b3
2.31
0.165
0.4
10
250
10
2
Min.
Typ.
Max.
400
1.0
Units
kHz
V
V
V
V
µA
ns
pF
I
SINK
=3mA
2
Conditions
Based upon I C master clock
Input is between 0.33V and 2.31V
With a bus capacitance from 10pF to
400pF
Gate Drivers
Parameter
GH, GL Rise and Fall Time
GH, GL Pull-up On-State Output
Resistance
GH, GL Pull-down On-State
Output Resistance
GH, GL Pull-down Off-State
Output Resistance
Min.
Typ.
30
6
3
50
Max.
Units
ns
Ω
Ω
kΩ
VIN=VCCD=0V
Conditions
At 10% to 90% of full scale pulse.
1nF C
load
© 2010 Exar Corporation
4/29
Rev. 1.1.4
XRP7714
Quad Channel Digital PWM Step Down Controller
BLOCK DIAGRAM
Channel 1
VOUT1
Feedback
ADC1/2
PreScaler
Vtar
DAC
SS & PD
Digital
PID
Hybrid
DPWM
Delay
Gate
Driver
BST1
GH1
LX1
GL1
PGND1
Isense1
Channel 2
VOUT2
Feedback
ADC1/2
PreScaler
Vtar
DAC
SS & PD
Digital
PID
BST2
–
6
GH2
LX2
Gate
Driver
Hybrid
DPWM
Dead
Time
GL2
PGND2
Isense2
VOUT3
Channel 3
VCCD
VOUT4
Channel 4
Isense1
Isense2
Isense3
LDO
VREF
Fault
Handling
PWR
Good
Current
ADC1/2
11-CH
MUX
Isense4
Vout1
Vout2
Vout3
Vout4
Vtj
I2C
OTP
Configuration
Registers
STBY LR
UVLO
VCC
VDD
GPIO 0-3
GPIO
OSC
CLOCK
SDA,SCL
VIN2
VIN1
LDOOUT
Fig. 2: XRP7714 Block Diagram
© 2010 Exar Corporation
5/29
Rev. 1.1.4
