Freescale Semiconductor
Technical Data
Document Number: MC34700
Rev. 5.0, 10/2009
9.0 to 18 V, Quad Output,
Integrated MOSFET Power
Supply
The 34700 is a compact, high-efficiency power supply with on-chip
power MOSFETs that features three step-down switching regulators
and one low dropout linear regulator. The switching regulators utilize
voltage mode control with external compensation, allowing flexibility in
optimizing the performance of the 34700 for a given application.
The 34700 is ideal for space constrained applications where
multiple power rails are required and simplicity of design and
implementation of the power supply is necessary. Over-voltage,
under-voltage, over-current, and over-temperature protection
features ensure robust and reliable operation. Fixed switching
frequency, internal soft-start, and internal power MOSFETs enable
rapid power supply design and development.
The 34700 is well suited for power supply designs in wide variety
of applications, including set top boxes, cable modems, laser
printers, fax machines, point-of-sale terminals, small appliances,
telecom line cards, and DVD players.
Typical Applications:
• Set Top Boxes and Receivers
• Cable Modems
• Networking Cards
• Telecom Line Cards
MC34700
POWER SUPPLY
98ASA10800D
32-Pin QFN, 5 x 5mm
ORDERING INFORMATION
Device
MC34700EP/R2
Temperature
Range (T
A
)
-40°C to 85°C
Package
32 QFN
Features
• Three switching regulators: 2 synchronous and 1 non-
synchronous
• One low dropout linear regulator
• Output current capability:
• 1.5 A continuous on channel 1
• 1.25 A continuous on channels 2 and 3
• 400 mA continuous on channel 4
• Internal power MOSFETs on all channels
• Voltage feed-forward on channel 1
• ±1.5% Output voltage accuracy on all channels
• Cycle-by-cycle current limit and short-circuit protection
• Fixed 800 kHz switching frequency
• Internal soft-start
• Over-voltage, under-voltage and over-temperature
protection
• Open-drain power-good output signal
• Separate active-high enable input for each channel
• Pb-free packaging designated by suffix code EP
V
IN1
9 V - 18 V
VIN
VDDI
VGREG
PGOOD
VIN1
MC34700
VOUT1 VIN2 VIN3 BST1
SW1
COMP1
FB1
BST2
SW2
COMP2
VOUT1
2.0 - 5.25 V, 1.5 A
VOUT2
0.7 - 3.6 V, 1.25 A
Enable 1
Enable 2
Enable 3
Enable 4
EN1
EN1
EN1
EN_LDO
FB2
BST3
SW3
COMP3
VOUT3
0.7 - 3.6 V, 1.25 A
AGND
GND2
GND3
FB3
LDO_VIN
LDO
VOUT4
0.7 - 3.6 V, 0.4 A
LDO_FB
Freescale Semiconductor, Inc. reserves the right to change the detail specifications,
as may be required, to permit improvements in the design of its products.
© Freescale Semiconductor, Inc., 2009. All rights reserved.
INTERNAL BLOCK DIAGRAM
INTERNAL BLOCK DIAGRAM
VOUT1
Ramp
Generator
PGOOD
Supervisory
Logic
Channel 1
Regulator
Control
Feed
Forward
Bootstrap
Circuit
BST1
VIN1
Gate
Drive
SW1
EN1
EN2
EN3
EN4
EN_LDO
Main
System
Control
COMP1
FB1
Thermal Monitoring
Current Monitoring
System Reset
Ramp
Generator
Bootstrap
Circuit
BST2
VIN2
Bandgap
Reference
Channel 2
Regulator
Control
0.7V Internal
Reference
Gate
Drive
SW2
GND2
COMP2
VDDI
FB2
POR
VDDI
Internal
Regulator
VGREG
Bootstrap
Circuit
Oscillator
Ramp
Generator
BST3
VIN3
VIN
V
G
Regulator
Channel 3
Regulator
Control
Gate
Drive
SW3
LDO_VIN
GND3
COMP3
LDO
LDO_FB
FB3
AGND
Figure 2. 34700 Simplified Internal Block Diagram
34700
2
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
ABSOLUTE MAXIMUM RATINGS
Table 1. Maximum Ratings
All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or
permanent damage to the device. This is a stress only rating and operation at these or any other conditions above those indicated
in the operational sections of this specification is not implied.
Ratings
ELECTRICAL RATINGS
Input Voltages
Input Voltage
Input DC/DC1 Voltage, I
VIN
= 0
Input DC/DC2, 3, and LDO Voltage
Switch Node Voltages
Switch Node DC/DC1
Switch Node DC/DC2, DC/DC3
Bootstrap Voltages
Bootstrap DC/DC1
Bootstrap DC/DC2, DC/DC3
Bootstrap Voltage Referenced to Switch Node Voltage
Compensation (COMP1, 2, and 3), Feedback (FB1, FB2, FB3, LDO_FB), VDDI
All Other Pins (EN1, 2, 3, EN_LDO, PGOOD, VGREG, LDO, VOUT1)
ESD Voltage
(1)
Human Body Model (HBM) All Pins
THERMAL RATINGS
Operating Temperature
Ambient
Junction
Peak Package Temperature During Reflow
(2), (3)
Storage Temperature
THERMAL RESISTANCE
Thermal Resistance
(2)
Junction-to-Case
Junction-to-Ambient
Power Dissipation
T
A
= 25°C
T
A
= 70°C
T
A
= 85°C
T
ΘJC
T
ΘJA
P
D
2.5
1.3
1.0
6.7
37
W
°C/W
T
A
T
J
T
PPRT
T
STRG
-40 to +85
-40 to +125
300
-40 to +150
°C
°C
°C
V
BST1
V
BST2
, V
BST3
V
BST
- V
SW
-
-
V
ESD
+ 2000
-0.3 to 25
-0.3 to 14
-0.3 to 7
-0.3 to 3
-0.3 to 7
V
V
V
V
SW1
V
SW2
, V
SW3
-0.3 to 20
-0.3 to 7
V
V
IN
V
IN1
V
IN2,
V
IN3
,
V
INLDO
-0.3 to 20
-0.3 to 20
-0.3 to 7
V
V
Symbol
Value
Unit
Notes
1. ESD testing is performed in accordance with the Human Body Model (HBM) (C
ZAP
= 100 pF, R
ZAP
= 1500
Ω).
2.
3.
Pin soldering temperature limit is for 10 seconds maximum duration. Not designed for immersion soldering. Exceeding these limits may
cause malfunction or permanent damage to the device.
Freescale’s Package Reflow capability meets Pb-free requirements for JEDEC standard J-STD-020C. For Peak Package Reflow
Temperature and Moisture Sensitivity Levels (MSL), Go to www.freescale.com, search by part number [e.g. remove prefixes/suffixes
and enter the core ID to view all orderable parts. (i.e. MC33xxxD enter 33xxx), and review parametrics.
34700
Analog Integrated Circuit Device Data
Freescale Semiconductor
3
ELECTRICAL CHARACTERISTICS
STATIC AND DYNAMIC ELECTRICAL CHARACTERISTICS
STATIC AND DYNAMIC ELECTRICAL CHARACTERISTICS
Table 2. Electrical Characteristics
Characteristics noted under conditions 9.0 V
≤
V
IN
≤
18 V, - 40°C
≤
T
A
≤
85°C, GND = 0 V, unless otherwise noted. Typical
values noted reflect the approximate parameter means at T
A
= 25°C under nominal conditions, unless otherwise noted.
Characteristic
POWER SUPPLY
VIN Voltage
Maximum
Minimum
Standby Current
Operating Current
Internal Supply Voltage
POWER-ON RESET
VGREG Rising Threshold Voltage
VGREG Falling Threshold Voltage
VGREG Hysteresis Voltage
VGREG LINEAR REGULATOR
On Resistance
Output Voltage
Maximum Input dV/dT
BIAS VOLTAGES
VGREG Decoupling
VDDI Decoupling
ENABLE
Output Enable Logic High Threshold
Voltage
Output Enable Logic Low Threshold
Voltage
EN Input Resistance to Ground
Delay from Enable to Soft Start DC1
Delay from Enable to Soft Start DC2, DC3
REFERENCE
DC/DC 1, 2, 3 Reference Voltage
LDO Reference Voltage
OSCILLATOR
Switching Frequency
SOFT-START
Soft-start Duration DC1, 2, 3
Soft-start Duration LDO
t
SS_BUCKREG
t
SS_LDO
2.5
0.3
3.5
0.5
4.5
0.7
ms
ms
f
SW
760
800
840
kHz
V
REF1,2,3
V
REF_LDO
0.690
0.690
0.700
0.700
0.710
0.710
V
V
V
EN1,2,3
V
EN_LDO
V
EN1,2,3
V
EN_LDO
R
EN_IN
t
DELAY1
t
DELAY2,3
-
-
-
1.5
1.0
160
-
-
-
MΩ
ms
ms
0.78
-
-
-
-
0.61
V
V
VGREG = 5.0 V
VDDI = 2.5 V
C
VGREG
C
VDDI
-
-
1.0
1.0
-
-
μF
μF
VIN1 = VIN
I
VGREG
= 80 mA
R
VGREGIN
V
VGREG
V
IN_dV/dT
-
4.75
-
30
5.25
10
-
5.5
-
Ω
V
V/μs
V
VGREG_RISING
V
VGREG_FALLING
V
VGREG_HYS
3.5
3.0
0.2
4.0
3.4
0.55
4.5
4.0
1.0
V
V
V
V
EN1
= V
EN2
= V
EN3
= V
EN_LDO
= 0 V
V
EN1
= V
EN2
= V
EN3
= V
EN_LDO
= 5.0 V,
V
VIN
= 9.0 V, Load = 0 A
I
SDB
I
IN
V
DDI
V
IN
-
-
-
-
2.3
18
9.0
8.95
15.4
2.5
-
-
15
-
2.7
mA
mA
V
V
Test Conditions
Symbol
Min
Typ
Max
Unit
34700
4
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
STATIC AND DYNAMIC ELECTRICAL CHARACTERISTICS
Table 2. Electrical Characteristics (continued)
Characteristics noted under conditions 9.0 V
≤
V
IN
≤
18 V, - 40°C
≤
T
A
≤
85°C, GND = 0 V, unless otherwise noted. Typical
values noted reflect the approximate parameter means at T
A
= 25°C under nominal conditions, unless otherwise noted.
Characteristic
RAMP GENERATORS
Ramp Amplitude (DC/DC1)
VFF Gain (DC/DC1)
Ramp Amplitude (DC/DC2,3)
VFF Gain (DC/DC2,3)
Ramp Bottom (DC/DC1,2,3)
Min Duty Cycle (DC/DC1)
Max Duty Cycle (DC/DC1)
Min Duty Cycle (DC/DC2,3)
Max Duty Cycle (DC/DC2,3)
POWER-GOOD
O V Threshold, all regulators
UV Threshold, all regulators
PGOOD Output Low Level
PGOOD Reset Delay
PGOOD Glitch Rejection
BUCK CONVERTER 1
Maximum VIN1 Input Voltage
Minimum VIN1 Input Voltage
Maximum Output Voltage
Minimum Output Voltage
Maximum Output Current
Total System Accuracy
Peak Short-circuit Current Limit
High Side On Resistance
Equivalent Dropout Resistance
Error Amplifier DC Gain
Error Amplifier Unity-gain Bandwidth
Error Amplifier Slew Rate @ 15 pF
Current Limit Timer
Current Limit Retry Timeout Period
V
IN1
= 5.5 V, V
OUT
= 3.3 V, I
LOAD
= 2.0 A
V
IN
= 9.0V
V
IN
= 9.0V
V
IN1_MAX
V
IN1_MIN
V
DC1VOUTMAX
V
DC1VOUTMIN
IOUT
DC1MAX
ΔV
OUT1
I
SHORT1
R
DS(ON)_HS
R
DO
A
EA
GBW
SR
t
LIM1
t
TIMEOUT1
-
-
-
-
-
-1.5
2.5
-
-
-
-
-
-
-
18
9.0
5.25
2.0
1.5
-
-
150
183
110
4.0
1.8
10
100
-
-
-
-
-
1.5
4.5
-
-
-
-
-
-
-
V
V
V
V
A
%
A
mΩ
mΩ
dB
MHz
V/μs
ms
ms
Percentage of setpoint
Percentage of setpoint
I
SINK
= 6.0 mA
Δ
OV_TH
Δ
UV_TH
V
OL_PGOOD
t
PG-RESET
t
PG-FILTER
-
92
-
-
-
0.4
100
10
108
-
-
%
%
V
μs
μs
I
LOAD1
= 0 A
I
LOAD1
= 0 A
I
LOAD1
= 0 A
I
LOAD1
= 0 A
V
FF_GAIN2
x P
VIN2
, P
VIN2
= 6.0 V
V
FF_GAIN1
x P
VIN1
, P
VIN1
= 18 V
V
RAMP_AMP1
V
FF_GAIN1
V
RAMP_AMP2,3
V
FF_GAIN2,3
V
RAMP_OFFSET
D
1
D
1
D
2,3
D
2,3
-
-
-
-
-
-
68.4
-
83.6
1.0
0.055
1.25
0.208
0.2
-
-
0
-
-
16
-
0
-
-
-
V
P-P
V/V
V
P-P
V/V
V
%
%
%
%
Test Conditions
Symbol
Min
Typ
Max
Unit
34700
Analog Integrated Circuit Device Data
Freescale Semiconductor
5
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