ZL2101
N O T R E C O MM E
NDED FOR NEW
DESIGNS
RECOMMENDED
REPLACEMENT
PART
ZL2102
DATASHEET
FN7730
Rev 0.00
January 23, 2012
6A Digital Synchronous Step-Down DC/DC Converter with Auto Compensation
The ZL2101 is a 6A digital converter with auto compensation
and integrated power management that combines an
integrated synchronous step-down DC/DC converter with key
power management functions in a small package, resulting in
a flexible and integrated solution.
The ZL2101 can provide an output voltage from 0.54V to 5.5V
(with margin) from an input voltage between 4.5V and 14V.
Internal low r
DS(ON)
synchronous power MOSFETs enable the
ZL2101 to deliver continuous loads up to 6A with high
efficiency. An internal Schottky bootstrap diode reduces
discrete component count. The ZL2101 also supports phase
spreading to reduce system input capacitance.
Power management features such as digital soft-start delay
and ramp, sequencing, tracking, and margining can be
configured by simple pin-strapping or through an on-chip serial
port. The ZL2101 uses the PMBus™ protocol for
communication with a host controller and the Digital-DC bus
for interoperability between other Zilker Labs devices.
Features
• Integrated MOSFET Switches
• 6A Continuous Output Current
• ±1% Output Voltage Accuracy
• Auto Compensation
•
Snapshot™
Parametric Capture
• I
2
C/SMBus Interface, PMBus Compatible
• Internal Non-Volatile Memory (NVM)
Applications
• Telecom, Networking, Storage equipment
• Test and Measurement Equipment
• Industrial Control Equipment
• 5V and 12V Distributed Power Systems
Related Literature
•
AN2010
“Thermal and Layout Guidelines for Digital-DC™
Products”
•
AN2033
“Zilker Labs PMBus Command Set - DDC Products”
•
AN2035
“Compensation Using CompZL™”
100
V
OUT
= 3.3V
90
80
70
60
50
40
0.0
V
IN
= 12V
f
SW
= 200kHz
L = 6µH
1.0
2.0
3.0
I
OUT
(A)
4.0
5.0
6.0
EFFICIENCY (%)
FIGURE 1. ZL2101 EFFICIENCY
FN7730 Rev 0.00
January 23, 2012
Page 1 of 27
ZL2101
Typical Application Circuit
The following application circuit represents a typical implementation of the ZL2101. For PMBus operation, it is recommended to tie the
enable pin (EN) to SGND.
C
RA
4.7 µF
C
25
10 µF
C
R
4.7µF
F.B.
‡
DDC 34
V2P5 33
VRA 32
MGN 35
VR 31
DDC Bus
ENABLE
†
C
DD
2.2 µF
C
IN
100 µF
V
IN
12V
EN 36
VDDS 30
VDDP 29
VDDP 28
PGOOD
1 PG
2 DGND
3 SYNC
4 VSET
5 SA
VDDP 27
BST 26
SW 25
C
B
47nF
ZL2106
ZL2101
SW 24
SW 23
SW 22
SW 21
SW 20
L
OUT
2.2µH
I C/
SMBus
††
2
6 SCL
7 SDA
8 SALRT
14 SGND
15 PGND
9 FC
16 PGND
17 PG ND
V
OUT
3.3V
PGND 19
18 PGND
C
OUT
150 µF
e PAD
(SG ND)
Notes:
‡
Ferrite bead is optional for input noise suppression.
†
The DDC bus pull-up resistance will vary based on the capacitive loading of the bus including the number of devices
,
connected. The 10 k default value, assuming a maximum of 100 pF per device, provides the necessary 1 µs pull-up rise
time. Please refer to the Digital-DC Bus section for more details.
††
2
The I C/SMBus pull -up resistance will vary based on the capacitive loading of the bus including the number of devices
,
connected. Please refer to the I
2
C/SMBus specifications for more details.
FIGURE 2. 12V TO 3.3V/6A APPLICATION CIRCUIT (5ms SS DELAY, 5ms SS RAMP)
Block Diagram
V
IN
VDDS
V2P5
VDDP
BST
VRA
VR
EN
PG
MGN
VSET
CFG
SS
VTRK
DDC
SA
2.5V
LDO
5V
LDO
13 VSEN
12 VTRK
10 CFG
11 SS
7V
LDO
PWM
Control
&
Drivers
Power
Mgmt
DDC Bus
SMBus
SALRT
SW
V
OUT
VSEN
NVM
PGND
SDA
SCL
FIGURE 3. BLOCK DIAGRAM
FN7730 Rev 0.00
January 23, 2012
SYNC
Page 2 of 27
ZL2101
Pin Configuration
ZL2101
(36 LD QFN)
TOP VIEW
EN
MGN
DDC
V2P5
VRA
VR
VDDS
VDDP
VDDP
36
35
34
33
32
31
30
29
PG
DGND
SYNC
VSET
SA
SCL
SDA
SALRT
FC
28
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
27
26
25
ZL2101
ZL2106
24
23
22
Exposed Paddle
Connect to SGND
21
20
19
VDDP
BST
SW
SW
SW
SW
SW
SW
PGND
Pin Descriptions
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15, 16, 17,
18, 19
20, 21, 22,
23, 24, 25
26
27, 28, 29
30
LABEL
PG
DGND
SYNC
VSET
SA
SCL
SDA
SALRT
FC
CFG
SS
VTRK
VSEN
SGND
PGND
SW
BST
VDDP
VDDS
TYPE
(Note 1)
O
PWR
I/O, M
(Note 2)
I, M
I, M
I/O
I/O
O
I, M
I, M
I, M
I
I
PWR
PWR
I/O
PWR
PWR
PWR
DESCRIPTION
Power-good. This pin transitions high 100ms after output voltage stabilizes within regulation band.
Selectable open drain or push-pull output. Factory default is open drain.
Digital ground. Common return for digital signals. Connect to low impedance ground plane.
Clock synchronization pin. Used to set switching frequency of internal clock or for synchronization to
external frequency reference.
Output voltage select pin. Used to set V
OUT
set-point and V
OUT
max.
Serial address select pin. Used to assign unique SMBus address to each IC.
Serial clock. Connect to external host interface.
Serial data. Connect to external host interface.
Serial alert. Connect to external host interface if desired.
Auto compensation configuration pin. Used to set up auto compensation.
Configuration pin. Used to control the SYNC pin, sequencing and enable tracking.
Soft-start pin. Used to set the ramp delay and ramp time, sets UVLO and configure tracking.
Track sense pin. Used to track an external voltage source.
Output voltage positive feedback sensing pin.
Common return for analog signals. Connect to low impedance ground plane.
Power ground. Common return for internal switching MOSFETs. Connect to low impedance ground plane.
Switching node (level-shift common).
Bootstrap voltage for level-shift driver (referenced to SW).
Bias supply voltage for internal switching MOSFETs (return is PGND).
IC supply voltage (return is SGND).
FN7730 Rev 0.00
January 23, 2012
CFG
SS
VTRK
VSEN
SGND
PGND
PGND
PGND
PGND
FIGURE 4.
Page 3 of 27
ZL2101
Pin Descriptions
(Continued)
PIN
31
32
33
34
35
36
ePad
NOTES:
1. I = Input, O = Output, PWR = Power or Ground, M = Multi-mode pins. Please refer to Section “Multi-mode Pins” on page 11.
2. The SYNC pin can be used as a logic pin, a clock input or a clock output.
LABEL
VR
VRA
V2P5
DDC
MGN
EN
SGND
TYPE
(Note 1)
PWR
PWR
PWR
I/O
I
I
PWR
DESCRIPTION
Regulated bias from internal 7V low-dropout regulator (return is PGND). Decouple with a 4.7µF capacitor to
PGND.
Regulated bias from internal 5V low-dropout regulator for internal analog circuitry (return is SGND).
Decouple with a 4.7µF capacitor to SGND.
Regulated bias from internal 2.5V low-dropout regulator for internal digital circuitry (return is DGND).
Decouple with a 10µF capacitor.
Digital-DC Bus (open drain). Interoperability between Zilker Labs devices.
Margin pin. Used to enable margining of the output voltage.
Enable pin. Used to enable the device (active high).
Exposed thermal pad. Common return for analog signals. Connect to low impedance ground plane.
Ordering Information
PART NUMBER
(Notes 4, 5)
ZL2101ALAF
ZL2101ALAFT (Note 3)
ZL2101ALAFTK (Note 3)
ZL2101EVAL1Z
NOTES:
3. Add “-T*” suffix for tape and reel. Please refer to
TB347
for details on reel specifications.
4. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin
plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pb-free
products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
5. For Moisture Sensitivity Level (MSL), please see device information page for
ZL2101.
For more information on MSL please see techbrief
TB363.
PART MARKING
2101
2101
2101
Evaluation Board
TEMP RANGE
(°C)
-40 to +85
-40 to +85
-40 to +85
PACKAGE
36 Ld 6mmx6mm QFN
36 Ld 6mmx6mm QFN
36 Ld 6mmx6mm QFN
PKG.
DWG. #
L36.6x6C
L36.6x6C
L36.6x6C
FN7730 Rev 0.00
January 23, 2012
Page 4 of 27
ZL2101
Table of Contents
Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Typical Performance Curves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
ZL2101 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Digital-DC Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Power Conversion Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Power Management Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Multi-mode Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Pin-strap Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Resistor Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
I2C/SMBus Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Power Conversion Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Internal Bias Regulators and Input Supply Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
High-side Driver Boost Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Output Voltage Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Start-up Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Soft-start Delay and Ramp Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Power-good (PG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Switching Frequency and PLL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Configuration A: SYNC OUTPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Configuration B: SYNC INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Configuration C: SYNC AUTO DETECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Component Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Design Goal Trade-offs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Inductor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Output Capacitor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Input Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Bootstrap Capacitor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CV2P5 Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CVR Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CVRA Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Thermal Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Current Sensing and Current Limit Threshold Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Loop Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Driver Dead-time Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Power Management Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Input Undervoltage Lockout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Output Overvoltage Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Output Pre-Bias Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Output Overcurrent Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Thermal Overload Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Voltage Tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Tracking Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Tracking Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Tracking Configured by Pin-Strap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Voltage Margining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
I2C/SMBus Communications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
I2C/SMBus Device Address Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Digital-DC Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Phase Spreading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Output Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Fault Spreading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Monitoring via I2C/SMBus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Snapshot™ Parametric Capture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Non-Volatile Memory and Device Security Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Package Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
FN7730 Rev 0.00
January 23, 2012
Page 5 of 27