XR77128
Quad Output Digital PWM/PFM
Universal PMIC
FEATURES
General Description
The XR77128 is a quad channel digital Pulse Width Modulated (PWM)
step down (buck) controller. A wide 4.75V to 5.5V and 5.5V to 25V input
voltage range allows for single supply operation from standard power
rails.
With integrated FET gate drivers, two LDOs for standby power and a
105kHz to 1.23MHz independent channel to channel programmable
constant operating frequency, the XR77128 reduces overall component
count, solution footprint and optimizes conversion efficiencies. A
selectable digital Pulse Frequency Mode (PFM) capable of better than
80% efficiency at light current load and low operating current allow for
portable and Energy Star compliant applications. Each XR77128
channel’s output voltage is individually programmable down to 0.6V with a
resolution of 2.5mV, and is configurable for precise soft start and soft stop
sequencing, including delay and ramp control.
The XR77128 operations are fully controlled via a SMBus-compliant I
2
C
interface allowing for advanced local and/or remote reconfiguration, full
performance monitoring and reporting as well as fault handling.
Built-in independent output Over-Voltage, Over-Temperature, Over-
Current and Under-Voltage Lockout protections insure safe operation
under abnormal operating conditions.
The XR77128 is offered in a RoHS compliant, “green”/halogen free 44-pin
TQFN package.
Quad Channel Step-down Controller
Digital PWM 105kHz-1.23MHz Operation
Individual Channel Frequency Selection
Patented digital PFM with Ultrasonic mode
Patented Over Sampling Feedback
Programmable 5 coefficient PID control
Integrated MOSFET Drivers
Supports DrMOS devices
4.75V to 5.5V and 5.5V to 25V Input Voltage
0.6V to 5.5V Output Voltage (higher with
external feedback resistors)
SMBus Compliant I
2
C Interface
Full Power Monitoring and Reporting
3 x 15V Capable PSIO + 2 x GPIOs
Full Start/Stop Sequencing Support
Built-in Thermal, Over-Current, UVLO and
Output Over-Voltage Protections
On Board 5V and LDOOUT Standby LDOs
On Board Non-Volatile Memory
Supported by PowerArchitect™ 5.2 or later
APPLICATIONS
Industrial Control Systems
Automatic Test Equipment
Video Surveillance Systems
Automotive Infotainment
Ordering Information –
back page
Typical Application
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Rev 1B
XR77128
Absolute Maximum Ratings
Stresses beyond the limits listed below may cause
permanent damage to the device. Exposure to any
Absolute Maximum Rating condition for extended periods
may affect device reliability and lifetime.
VCCD, LDO5, LDOOUT, GLx, VOUTx........................-0.3V to 7.0V
ENABLE, V5EXT.........................................................-0.3V to 7.0V
GPIO0/1, SCL, SDA.................................................................6.0V
PSIO Inputs, BFB......................................................................18V
DVDD, AVDD...........................................................................2.0V
VCC..........................................................................................28V
LX#.................................................................................-1V to 28V
BSTx, GHx........................................................................VLx + 6V
Storage Temperature.............................................-65°C to +150°C
Power Dissipation................................................Internally Limited
Lead Temperature (Soldering, 10 sec)..................................300°C
ESD Rating (HBM - Human Body Model).................................2kV
Operating Conditions
Input Voltage Range VCC.............................................5.5V to 25V
Input Voltage Range VCC = LDO5.............................4.75V to 5.5V
VOUT1, 2, 3, 4.........................................................................5.5V
Junction Temperature Range................................-40°C to +125°C
JEDEC Thermal Resistance
JA
.........................................32°C/W
Electrical Characteristics
Unless otherwise noted: T
J
= 25°C, VCC = 5.5V to 25V, V5EXT open. Limits applying over the full operating temperature
range are denoted by a “•”
Symbol
Quiescent Current
I
SUPPLY
VCC Supply Current
SHUTDOWN
EN = 0V, VCC = 12V
STANDBY
I/Os programmed as inputs, VCC = 12V,
EN = 5V
2ch PFM
2 channels on set at 5V, VOUT forced to
5.1V, no load, non-switching, ultra-sonic
off, VCC = 12V, no I
2
C activity
4ch PFM
4 channels on set at 5V, VOUT forced to
5.1V, no load, non-switching, ultra-sonic
off, VCC = 12V, no I
2
C activity
4ch PWM
All channels enabled, f
sw
= 600kHz, gate
drivers unloaded, no I
2
C activity
18
mA
4.0
mA
10
20
μA
Parameter
Conditions
Min
Typ
Max
Units
550
650
μA
3.1
mA
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Rev 1B
XR77128
Symbol
V
ENABLE
I
LEAK
Parameter
ENABLE Turn On Threshold
ENABLE Pin Leakage Current
Conditions
VCC = 12V, Enable Rising
EN = 5V
EN = 0V
Input Voltage Range and Undervoltage Lockout
VCC
VCC Range
with VCC connected to LDO5
Voltage Feedback Accuracy and Output Voltage Set Point Resolution
V
A_VO
VOUT Regulation Accuracy
Low Output Range
0.6 ≤ VOUT ≤ 1.6V, PWM operation
Mid Output Range
0.6 ≤ VOUT ≤ 3.2V, PWM operation
High Output Range
0.6 ≤ VOUT ≤ 5.5V, PWM operation
V
R_VO
V
NATIVE
VOUT Regulation Range
VOUT Native Set Point Resolution
Without external divider network
Low Range
Mid Range
High Range
V
FINE
VOUT Fine Set Point Resolution
1
Low Range
Mid Range
High Range
R
IN
VOUT Input Resistance
Low Range
Mid Range
High Range
R
IN
VOUT Input Resistance in PFM
Low Range
Mid Range
High Range
V
SET_PG
Power Good and OVP Set Point
Range (from set point)
Low Range
Mid Range
High Range
V
SET_PG
Power Good and OVP Set Point
Accuracy
Low Range
Mid Range
High Range
V
SET_BF
V
RES_BF
V
A_BF
BFB Set Point Range
BFB Set Point Resolution
BFB Accuracy
-0.5
-155
-310
-620
-5
-10
-20
9
1
0.5
-5
Min
0.65
Typ
Max
0.95
Units
V
μA
μA
3.6
-10
10
5.5
4.75
25
5.5
V
V
5
12.5
10
25
20
50
5.5
12.5
25
50
2.5
5
10
120
80
65
10
1
0.67
157.5
315
630
5
10
20
16
mV
mV
mV
mV
mV
mV
V
mV
mV
mV
mV
mV
mV
kΩ
kΩ
kΩ
MΩ
MΩ
MΩ
mV
mV
mV
mV
mV
mV
V
V
V
-12.5
-10
-25
-20
-50
0.6
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Rev 1B
XR77128
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Current and AUX ADC (Monitoring ADCs)
V
A_CS
Current Sense Accuracy
Low Range (≤120mV), -60mV applied
-2.5
-6.25
-5
±1.25
2.5
6.25
mV
mV
mV
mV
LSB
LSB
mV
mV
High Range (≤280mV), 150mV applied
±2.5
5
12.5
-12.5
±0.4
±0.4
INL
CS
DNL
CS
V
SET_CS
Current Sense ADC INL
Current Sense DNL
Current Limit Set Point Resolution
and Current Sense ADC Resolution
Current Sense ADC Range
Low Range (≤120mV)
High Range (≤280mV)
1.25
2.5
-120
-280
15
30
60
-1
4.6
200
1
25
20
40
V
CS
Low Range (≤120mV)
High Range (≤280mV)
mV
mV
mV
mV
mV
LSB
V
mV
V
ADC_VO
VOUT ADC Resolution
Low Range
Mid Range
High Range
LSB
ADC
V
ADC
V
R_ADC
V
A_ADC
T
R_ADC
T
ADC
VOUT ADC Accuracy
VCC ADC Range
VCC ADC Resolution
VCC ADC Accuracy
Die Temp ADC Resolution
Die Temp ADC Range
Output value is in Kelvin
VCC ≤ 20V
-1
5
-44
1
LSB
°C
156
°C
Linear Regulators
V
O_LDO5
LDO5 Output Voltage
5.5V ≤ VCC ≤ 25V
0mA < I
LDO5OUT
< 130mA, LDOOUT off
LDO5 Fault Set
VCC Rising
VCC Falling
4.85
5.0
5.15
V
I
CL_LDO5
LDO5 Current Limit
LDO5 UVLO
LDO5 PGOOD Hysteresis
LDO5 Bypass Switch Resistance
Bypass Switch Activation Threshold
Bypass Switch Activation Hysteresis
LDOOUT Output Voltage
135
4.6
155
180
mA
V
375
1.1
1.5
2.5
150
mV
Ω
%
mV
3.45
V
V5EXT Rising, % of threshold setting
V5EXT Falling
4.6V ≤ LDO5 ≤ 5.5V
0mA < I
LDOOUT
< 50mA
LDOOUT set to 3.3V
LDOOUT Fault Set, LDOOUT set to 3.3V
ENABLE transition from logic low to high.
Once LDO5 in regulation, above limits
apply.
2.5
3.15
3.3
LDOOUT Current Limit
Maximum total LDO loading during
ENABLE start-up
50
85
75
mA
mA
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Rev 1B
XR77128
Symbol
Parameter
Conditions
Min
Typ
Max
Units
PWM Generators and Oscillator
f
SW
Switching Frequency Range
Switching Frequency Accuracy
f
CLKIN
CLOCK IN Synchronization Fre-
quency
When synchronizing to an external clock
(Range 1)
When synchronizing to an external clock
(Range 2)
I
2
C and GPIOs
2
V
IL
V
IH
Input Pin Low Level
Input Pin High Level
Input Pin Leakage Current
V
OL
V
OH
Output Pin Low Level
Output Pin High Level
I
SINK
= 1mA
I
SOURCE
= 1mA
I
SOURCE
= 0mA
Output Pin High-Z Leakage Current
(GPIO pins only)
Maximum Sink Current
I/O Frequency
PSIOs
3
V
IL
V
IH
V
IH
Input Pin Low Level
Input Pin High Level
Input Pin High Level
Input Pin Leakage Current
V
OL
V
OH
Output Pin Low Level
Output Pin High Level
I
SINK
= 3mA
Open Drain. External pull-up resistor to
user supply.
PSIO0 and PSIO1
PSIO2
2
1.35
1
0.4
15
0.8
V
V
V
μA
V
V
Open Drain Mode
2.4
3.3
3.6
10
1.35
1
0.4
0.8
V
V
μA
V
V
V
μA
Steps defined in table
105
-5
20
25.7
1230
5
31
kHz
%
MHz
10
12.8
15.5
MHz
1
30
mA
MHz
Output Pin High-Z Leakage Current
(PSIO pins only)
I/O Frequency
SMBus (I
2
C) Interface
V
IL
V
IH
V
HYS
Input Pin Low Level
Input Pin High Level
Hysteresis of Schmitt Trigger Inputs
V
IO
= 3.3V ±10%
V
IO
= 3.3V ±10%
V
IO
= 3.3V ±10%
0.7V
IO
0.05
V
IO
10
μA
5
MHz
0.3V
IO
V
V
V
V
OL
I
LEAK
Output Pin Low Level (open drain or
collector)
Input Leakage Current
I
SINK
= 3mA
Input is between 0.1V
IO
and 0.9V
IO
-10
0.4
V
10
μA
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exar.com/XR77128
Rev 1B
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