ETC PIP250M

PIP250M
Integrated buck converter
Rev. 02 — 21 February 2003
Product data
M3D797
1. Description
The PIP250M is a fully integrated synchronous buck converter intended for use as a
point-of-load regulator. It contains two N-channel power MOSFETs, a Schottky diode
and a voltage mode, pulse width modulated (PWM) controller. The controller features
include overcurrent and overvoltage protection and undervoltage lockout functions.
By combining the power components and the controller into a single component,
stray inductances are virtually eliminated, resulting in lower switching losses and a
compact, efficient design with minimal external component count.
2. Features
■
■
■
■
■
■
■
■
■
Output current up to 15 A
Single supply 5 V operation
Fixed 300 kHz operating frequency
Voltage mode control
Minimum regulated output voltage 0.8 V
Internal soft start
Overcurrent protection
Overvoltage protection
Remote sensing.
■
■
■
■
■
■
■
High-current point-of-load regulation
Distributed power architectures
Multiple output telecom power supplies
Microprocessor and Digital Signal Processing (DSP) supplies
Computer peripheral supplies
Cable modems
Set-top boxes.
3. Applications
4. Ordering information
Table 1:
Ordering information
Type number
PIP250M
Package
Name
Description
Version
HVQFN68
plastic, thermal enhanced very thin quad flat package; no leads; SOT687-1
68 terminals; body 10 × 10 × 0.85 mm
PIP250M
Philips Semiconductors
Integrated buck converter
5. Block diagram
VDDC
61, 62
7
6.0 V
REGULATOR
40 µA
POWER ON
RESET
PIP250M
CB
1, 2
5
OCSET/
ENABLE
PHASE
strobe
0.8 V
REFERENCE
9, 12 to 17,
25, 26, PAD2
SOFT
START
1V
OVP
UVP
0.5 V
0.8 V
FB
VSSC
35 dB
8, 60, 67
68, PAD1
10, 18 to 24,
27 to 41
59, PAD3
CONTROL
LOGIC
PWM
65
VDDO
VO
VDDC
ERROR
AMP
300 kHz
OSCILLATOR
42 to 58
VSSO
03aj54
Fig 1. Block diagram
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
2 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
6. Pinning information
VO
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VDDC
VDDC
VSSC
FB
n.c.
n.c.
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
VSSC
VSSC
n.c.
6.1 Pinning
OCSET/ENABLE
OCSET/ENABLE
n.c.
n.c.
PHASE
n.c.
CB
VSSC
VDDO
VO
n.c.
VSSC
PAD 1
VO
PAD 3
VDDO
PAD 2
PIP250M
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VSSO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VO
VDDO
VDDO
VO
VO
VO
VO
VO
VO
VO
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
VDDO
VDDO
VDDO
VDDO
VDDO
VDDO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
03aj53
Grey area denotes terminal 1 index area.
Fig 2. Pin configuration (footprint view).
6.2 Pin description
Table 2:
Symbol
Pin description
Pin
[1]
I/O
Description
-
output stage supply voltage
VDDO
9, 12 to 17,
25, 26, PAD2
VSSO
42 to 58
-
output stage ground
VDDC
61, 62
-
control circuit supply voltage
-
control circuit ground
O
output
VSSC
8, 60, 67, 68,
PAD1
[1]
VO
10, 18 to 24,
27 to 41, 59,
PAD3
[1]
CB
7
I/O
bootstrap capacitor connection
PHASE
5
I
sense connection for current limit
OCSET/
ENABLE
1, 2
I
current limit set and enable input
FB
65
I
feedback input
-
no internal connection
n.c.
3, 4, 6, 11, 63,
64, 66
[2]
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
3 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
[1]
[2]
PAD1, PAD2 and PAD3 are electrical connections and must be soldered to the printed circuit board
All n.c. pins should be connected to VSSC.
7. Functional description
7.1 Pin functions
7.1.1
Output stage supply (VDDO, VSSO)
The power output stage of the PIP250M consists of two N-channel, power MOSFETs
and a Schottky diode configured as a synchronous buck converter. The drain of the
upper MOSFET is connected to the positive conversion supply (VDDO), and the
source of the lower MOSFET is connected to power ground (VSSO). The Schottky
diode is connected between the source and drain of the lower MOSFET.
7.1.2
Output voltage (VO)
VO is the switched node of the power MOSFET output stage. This node is connected
internally to the source of the upper MOSFET and the drain of the lower MOSFET.
7.1.3
Control circuit supply (VDDC, VSSC)
VDDC is the positive supply to the control circuit. VSSC is the control circuit ground. All
control voltages are measured with respect to VSSC.
7.1.4
Bootstrap capacitor connection (CB)
The upper MOSFET driver stage is powered from the CB pin.
7.1.5
Voltage feedback pin (FB)
The FB pin is connected to the inverting input of the error amplifier, and to the inputs
of the overvoltage and undervoltage comparators.
7.1.6
Current limit set and enable input (OCSET/ENABLE)
The overcurrent threshold is set by an external resistor between VDDO and
OCSET/ENABLE. The PIP250M can be shut down by pulling this pin LOW.
7.1.7
Sense connection for current limit (PHASE)
The PHASE input is normally connected externally to the power output stage
switched node (VO). The voltage on the PHASE input is compared with the voltage
on the OCSET/ENABLE input during the interval when the upper MOSFET is on. The
overcurrent trip operates if the voltage on the PHASE input is lower than the voltage
on the OCSET/ENABLE input.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
4 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
7.2 Operation
7.2.1
Single supply operation
10 Ω
5V
D1
VDDC
CB
VDDO
100 nF
VO
1 µF
100
µF
PIP250M
VSSC
VSSO
03ak42
Fig 3. Single supply operation.
Operation of the PIP250M from a single 5 V conversion supply is shown in Figure 3.
The upper MOSFET gate driver stage is supplied from the CB pin. An external
bootstrap circuit, comprising D1 and the 100 nF capacitor generates a voltage on CB
of twice VDDO.
The control circuit supply, VDDC is protected from transients by a low pass filter
comprising a 10 Ω resistor and a 1 µF capacitor. These components should be
placed close to the device pins.
7.2.2
Regulated output voltage
The reference voltage of the PIP250M is 0.8 V. The regulated output voltage is set
using a resistive divider as shown in Figure 9. The resistors should be placed as
close as possible to the FB pin. Both resistors should be less than 1 kΩ in order to
avoid noise coupling. The 68 nF capacitor across the upper resistor improves the
control loop stability by adding a small amount of phase margin.
7.2.3
Power on reset
The PIP250M control circuit powers up when the voltage on VDDC rises above the
start-up threshold voltage (typically 4.1 V). The control circuit stops operating when
the voltage on VDDC falls below the power-down threshold voltage (typically 3.6 V).
Once the voltage on VDDC is above the start-up threshold voltage, the PIP250M does
not produce pulses until the voltage on OCSET/ENABLE rises above the OCSET/
ENABLE start-up threshold voltage (typically 1.25 V).
7.2.4
Soft start
The soft start sequence prevents surge currents being drawn from the conversion
supply when the PIP250M is powered up into a high current load. The soft start
sequence is controlled by an internal digital counter. During the soft start sequence,
the reference voltage on the non inverting input of the error amplifier is increased
from zero up to the normal operating level of 0.8 V. The duration of the soft start
sequence is typically 2 ms.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
5 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
7.2.5
Overcurrent protection
5V
ROCSET
1 nF
OCSET/
ENABLE
VDDO
PIP250M
40 µA
OC
PHASE
VO
strobe
CONTROL
LOGIC
03ak44
Fig 4. Overcurrent protection.
The overcurrent protection function is shown in Figure 4. The overcurrent trip function
is enabled when the upper MOSFET gate drive signal is HIGH.
During this interval, the voltage on the PHASE input is compared with the voltage on
the OCSET/ENABLE input. If the voltage on the PHASE input is lower than the
voltage on the OCSET/ENABLE input, then the PIP250M detects an overcurrent trip
condition and turns off the gate drive to the upper MOSFET. There is an internal filter
with a time constant of 30 µs in series with the PHASE input. Since the switching
frequency is 300 kHz, this means that the overcurrent trip operates if the overcurrent
condition persists for10 switching cycles.
If three overcurrent pulses are detected, the PIP250M latches off and produces no
more pulses until it has been reset. To reset the PIP250M, the supply voltage (VDDC)
must be reduced below the power down reset threshold and then increased back up
to 5 V.
An external resistor (ROCSET) sets the overcurrent trip level. Figure 5 shows the
overcurrent trip level (ITRIP) as a function of ROCSET.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
6 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
03ak48
30
ITRIP
(A)
20
10
0
1
2
3
4
ROCSET (kΩ)
Fig 5. Overcurrent trip level as a function of ROCSET.
7.2.6
Undervoltage and overvoltage protection
With reference to Figure 1, the FB pin is connected internally to the overvoltage and
undervoltage comparators, labelled OVP and UVP respectively. In normal operation,
the voltage on FB is regulated at 0.8 V.
If the voltage on FB exceeds the overvoltage protection (OVP) threshold (1 V) for
longer than 30 µs, an overvoltage condition is detected, the gate drive signals to the
MOSFETs are disabled, and the PIP250M latches off. To reset the latch, the
PIP250M must be powered down by reducing VDDC below the power down reset
threshold and then increasing VDDC back up to 5 V.
If the voltage on FB drops below the undervoltage protection (UVP) threshold (0.5 V)
for longer than 30 µs, then an undervoltage condition is detected and the gate drive
signals to the MOSFET drivers are turned off. If three undervoltage pulses are
detected then the PIP250M latches off. To reset the PIP250M, the supply voltage
(VDDC) must be reduced below the power down reset threshold and then increased
back up to 5 V.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
7 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
8. Limiting values
Table 3: Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
VDDC
Min
Max
Unit
control circuit supply voltage
−0.3
+7
V
VDDO
output stage supply voltage
−0.3
+7
V
VPHASE
input voltage on PHASE
−0.3
+7
V
VOCSET
input voltage on OCSET
−0.3
+7
V
VFB
input voltage on FB
−0.3
+7
V
VO
output voltage
−0.3
+VDDO + 0.3
V
VCB
bootstrap voltage
−0.3
+15
V
IO(AV)
average output current
Tpcb ≤ 110 °C; Figure 6
-
15
A
repetitive peak output current
tp ≤ 10 µs; duty cycle ≤ 0.075
[1]
-
200
A
total power dissipation
Tpcb = 25 °C
[2]
-
20
W
Tpcb = 90 °C
[2]
IORM
Ptot
Conditions
-
7
W
Tj
junction temperature
−40
+125
°C
Tstg
storage temperature
−55
+150
°C
Vesd
electrostatic discharge voltage
-
2
kV
-
200
V
human body model; C = 100 pF;
R = 1500 Ω
[3]
machine model; C = 200 pF;
R = 10 Ω; L = 0.75 µH
[1]
[2]
[3]
Pulse width and repetition rate limited by maximum value of Tj.
Assumes a thermal resistance from junction to printed-circuit board of 5 K/W
The PIP250M meets class 2 for Human Body Model and class M3 for Machine Model.
03ak50
16
IO(AV)
(A)
12
8
4
0
0
50
100
Tpcb (°C)
150
Circuit of Figure 9; VDDC = 5 V; VDDO = 5 V; VO = 2.5 V.
Fig 6. Average output current as a function of printed-circuit board temperature.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
8 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
9. Thermal characteristics
Table 4:
Thermal characteristics
Symbol
Parameter
Rth(j-pcb)
thermal resistance from
junction to printed-circuit
board
Rth(j-a)
thermal resistance from
junction to ambient
Rth(j-c)
thermal resistance from
junction to case
Conditions
Min
Typ
Max
Unit
-
4
5
K/W
no thermal vias
-
25
-
K/W
with thermal vias
-
20
-
K/W
with thermal vias and forced
air cooling; airflow = 0.8 ms-1
(150 LFM)
-
15
-
K/W
-
11
-
K/W
Min
Typ
Max
Unit
device mounted on FR4
printed-circuit board; copper
area around device 25 × 25 mm
measured on upper surface of
package.
10. Characteristics
Table 5:
Characteristics
VDDC = 5 V; Tamb = 25 °C; circuit of Figure 9 unless otherwise specified.
Symbol
Parameter
Conditions
Control circuit supply
VDDC
control circuit supply voltage −40 °C ≤ Tj ≤ +125 °C
-
5
-
V
IDDC
control circuit supply current
-
24
-
mA
Power dissipation
Ptot
power dissipation
VDDC = 5 V; VDDO = 5 V;
VO = 2.5 V; IO(AV) = 15 A;
Figure 7
-
3.6
-
W
η
efficiency
VDDC = 5 V; VDDO = 5 V;
VO = 2.5 V; IO(AV) = 15 A;
Figure 8
-
88
-
%
Power-on Reset
VDDC(th)su
start-up threshold control
circuit supply voltage
VDDC increasing;
VOCSET = 4.5 V
3.85
4.1
4.35
V
VDDC(th)sd
shut-down threshold control
circuit supply voltage
VDDC decreasing;
VOCSET = 4.5 V
3.25
3.7
3.98
V
Vhys
hysteresis
VOCSET(th)su start-up threshold voltage
OCSET
VOCSET = 4.5 V
0.3
0.5
0.7
V
VOCSET increasing
0.8
1.25
2.0
V
measured at FB pin
0.78
0.8
0.82
V
Reference
Vi(ref)FB
reference voltage
Oscillator
fosc
oscillator frequency
250
300
350
kHz
Vosc(p-p)
oscillator ramp amplitude
(peak-to-peak value)
-
1.75
-
V
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9397 750 10904
Product data
Rev. 02 — 21 February 2003
9 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
Table 5:
Characteristics…continued
VDDC = 5 V; Tamb = 25 °C; circuit of Figure 9 unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Error amplifier
Gol
open loop gain
-
35
-
dB
GB
Gain bandwidth product
-
17
-
MHz
Overvoltage, overcurrent and undervoltage protection
VFB(th)OV
overvoltage threshold
feedback voltage
voltage on FB increasing
1.0
1.1
-
V
VFB(th)UV
undervoltage threshold
feedback voltage
voltage on FB decreasing
-
0.5
0.6
V
IOCSET
OCSET sink current
VOCSET = 4.5 V
35
40
45
µA
tD(OC)
overcurrent trip delay
-
30
-
µs
tD(UV)
undervoltage trip delay
-
30
-
µs
tSS
soft start interval
-
2
-
ms
03ak51
4
03al76
100%
η
(%)
Ptot
(W)
95%
(1)
3
(2)
90%
(3)
2
85%
(4)
(5)
1
0
80%
75%
0
4
8
12
16
IO(AV) (A)
See circuit of Figure 9.
2
5
7
10
12
15
IO(AV) (A)
See circuit of Figure 9.
VDDC = 5 V; VDDO = 5 V; VO = 2.5 V
(1) VO = 3.3 V
(2) VO = 2.5 V
(3) VO = 1.8 V
(4) VO = 1.5 V
(5) VO = 1.2 V
Fig 7. Total power dissipation as a function of average
output current; typical values.
Fig 8. Total solution efficiency as a function of
average output current; typical values.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
10 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
11. Application information
conversion
supply
(5 V)
1.2 µH
10 Ω
BAW62
100 nF
2.7 kΩ
1 µF
1.2 kΩ
shut
down
VDDC
CB
VDDO
PIP250M
OCSET/
ENABLE
VSSC
2000
µF
2.5 µH
VO
PHASE
VSSO
FB
2000 µF
output voltage
(2.5 V)
VO
4.7
κΩ
6.8 nF
BSH112
2.2
κΩ
03ak52
Fig 9. Typical application circuit.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
11 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
12. Marking
terminal 1
index area
TYPE No.
Design centre
k = Hazel Grove, UK
Release status code
X = Development Sample
Y = Customer Qualification Sampl
blank = Released for Supply
DIFFUSION LOT No.
Diffusion centre
= Hazel Grove, UK
MANUFACTURING CODE
hfkYYWWY
COUNTRY OF ORIGIN
Assembly centre
f = Anam Korea
Date code
YY = last two digits of year
WW = week number
03ag38
03ai72
TYPE No: PIP250M-NN (NN is version number)
DIFFUSION LOT No: 7 characters
MANUFACTURING CODE: see Figure 11
COUNTRY OF ORIGIN: Korea
Fig 10. SOT687-1 marking.
Fig 11. Interpretation of manufacturing code.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
12 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
13. Package outline
HVQFN68: plastic thermal enhanced very thin quad flat package; no leads;
68 terminals; body 10 x 10 x 0.85 mm
SOT687-1
B
D
A
D1
terminal 1
index area
A
E1 E
A4
A1
c
detail X
C
e1
e
18
34
L
y
y1 C
v M C A B
w M C
b
35
17
Eh1
e
Eh
e2
Eh1
1
terminal 1
index area
51
68
52
Dh
Dh
0
2.5
X
5 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
mm
A
max.
A1
A4
b
1
0.05
0.00
0.80
0.65
0.30
0.18
c
0.2
D
D1
10.15 9.95
9.85 9.55
Dh
E
E1
Eh
3.8
3.5
10.15
9.85
9.95
9.55
7.85
7.55
Eh1
3.8
3.5
REFERENCES
OUTLINE
VERSION
IEC
JEDEC
JEITA
SOT687-1
---
MO-220
---
e
0.5
e1
8
e2
L
v
w
y
y1
8
0.75
0.50
0.1
0.05
0.05
0.1
EUROPEAN
PROJECTION
ISSUE DATE
02-04-24
02-10-18
Fig 12. SOT687-1.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
13 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
14. Soldering
14.1 Introduction to soldering HVQFN packages
The HVQFN package is a near Chip Scale Package (CSP) with a copper lead frame.
It is a leadless package, where electrical contact to the printed circuit board is made
through metal pads on the underside of the package. In addition to the small pads
around the periphery of the package, there are large pads on the underside that
provide low thermal resistance, low electrical resistance, low inductance connections
between the power components inside the package and the PCB. It is this feature of
the HVQFN package that makes it ideally suited for low voltage, high current DC to
DC converter applications.
Electrical connection between the package and the printed circuit board is made by
printing solder paste on the printed circuit board, placing the component and
reflowing the solder in a convection or infra-red oven. The solder reflow process is
shown in Figure 13 and the typical temperature profile is shown in Figure 14. To
ensure good solder joints, the peak temperature Tp should not exceed 220° C, and
the time above liquidus temperature should be less than 1.25 minutes. The ramp rate
during preheat should not exceed 3 K/s. Nitrogen purge is recommended during
reflow.
SOLDER PASTE
PRINTING
03aj26
300
POST PRINT
INSPECTION
Temp
(°C)
COMPONENT
PLACEMENT
Tp
200
Tr
PRE REFLOW
INSPECTION
1 min max
REFLOW SOLDERING
100
rate of rise of
temperature < 3 K/s
POST REFLOW INSPECTION
(PREFERABLY X-RAY)
REWORK AND
TOUCH UP
0
0
03aj25
Fig 13. Typical reflow soldering process flow.
1
2
time (minutes)
3
Fig 14. Typical reflow soldering temperature profile.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
1.25 min max
Te
Rev. 02 — 21 February 2003
14 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
14.2 Rework guidelines
Since the solder joints are largely inaccessible, only the side fillets can be touched
up. If there are defects underneath the package, then the whole package has to be
removed.
The first step in component removal is to reflow the solder joints. It is recommended
that the board is heated from the underside using a convective heater whilst hot air or
gas is directed at the upper surface of the component. Nozzles should be used to
direct the hot air or gas to minimize heating of adjacent components. Excessive
airflow should be avoided since this may cause the package to skew. An airflow of 15
to 20 liters per minute is usually adequate.
Once the solder joints have reflowed, the component should be lifted off the board
using a vacuum pen.
The next step is to clean the solder pads using solder braid and a blade shaped
soldering tool. Finally, the pads should be cleaned with a solvent. The solvent is
usually specific to the type of solder paste used in the original assembly and the
paste manufacturers recommendations should be followed.
15. Mounting
15.1 PCB design guidelines
The terminals on the underside of the package are rectangular in shape with a
rounded edge on the inside. Electrical connection between the package and the
printed-circuit board is made by printing solder paste onto the PCB footprint followed
by component placement and reflow soldering. The PCB footprint shown in Figure 15
is designed to form reliable solder joints.
The use of solder resist between each solder land is recommended. PCB tracks
should not be routed through the corner areas shown in Figure 15. This is because
there is a small, exposed remnant of the lead frame in each corner of the package,
left over from the cropping process.
Good surface flatness of the PCB lands is desirable to ensure accuracy of placement
after soldering. Printed-circuit boards that are finished with a roller tin process tend to
leave small lumps of tin in the corners of each land. Levelling with a hot air knife
improves flatness. Alternatively, an electro-less silver or silver immersion process
produces completely flat PCB lands.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
15 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
1 SP
(8×)
0.4 SP
0.6 Cu
0.4 SP
0.28 Cu (68×)
1 SP
(8×)
11.15 OA 7.6 Cu 4.1
(2×)
(2×)
8.9 Cu 10.8 Cu
(2×)
(2×)
0.6 Cu
0.5 SP
(4×)
0.4 SP (2×)
0.9 SP
(10×)
e = 0.5
4.1
1 SP
(10×)
8.63 OA
(4×)
solder lands
MGW820
0.1
Cu pattern
0.2
clearance
0.025
solder paste
occupied area
Fig 15. PCB footprint for SOT687-1 package (reflow soldering).
15.2 Solder paste printing
The process of printing the solder paste requires care because of the fine pitch and
small size of the solder lands. A stencil thickness of 0.125 mm is recommended. The
stencil apertures can be made the same size as the PCB lands in Figure 15.
The type of solder paste recommended for HVQFN packages is “No clean”, Type 3,
due to the difficulty of cleaning flux residues from beneath the package.
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
16 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
16. Revision history
Table 6:
Revision history
Rev Date
02
20030221
CPCN
Description
-
Product data (9397 750 10904)
Modifications:
•
•
Table 2: Pin description OCSET changed to OCSET/ENABLE
Section 7:
– Dual supply operation deleted
– Regulated output voltage section added
– Overcurrent protection description clarified
– Figure 5 revised
•
Table 5:
– Typical value of IDDC changed from 20 mA to 24 mA
– Efficiency added
•
01
20021018
-
Figure 8 added.
Objective data (9397 750 10579)
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Product data
Rev. 02 — 21 February 2003
17 of 19
PIP250M
Philips Semiconductors
Integrated buck converter
17. Data sheet status
Level
Data sheet status[1]
Product status[2][3]
Definition
I
Objective data
Development
This data sheet contains data from the objective specification for product development. Philips
Semiconductors reserves the right to change the specification in any manner without notice.
II
Preliminary data
Qualification
This data sheet contains data from the preliminary specification. Supplementary data will be published
at a later date. Philips Semiconductors reserves the right to change the specification without notice, in
order to improve the design and supply the best possible product.
III
Product data
Production
This data sheet contains data from the product specification. Philips Semiconductors reserves the
right to make changes at any time in order to improve the design, manufacturing and supply. Relevant
changes will be communicated via a Customer Product/Process Change Notification (CPCN).
[1]
Please consult the most recently issued data sheet before initiating or completing a design.
[2]
The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at
URL http://www.semiconductors.philips.com.
[3]
For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status.
18. Definitions
19. Disclaimers
Short-form specification — The data in a short-form specification is
extracted from a full data sheet with the same type number and title. For
detailed information see the relevant data sheet or data handbook.
Life support — These products are not designed for use in life support
appliances, devices, or systems where malfunction of these products can
reasonably be expected to result in personal injury. Philips Semiconductors
customers using or selling these products for use in such applications do so
at their own risk and agree to fully indemnify Philips Semiconductors for any
damages resulting from such application.
Limiting values definition — Limiting values given are in accordance with
the Absolute Maximum Rating System (IEC 60134). Stress above one or
more of the limiting values may cause permanent damage to the device.
These are stress ratings only and operation of the device at these or at any
other conditions above those given in the Characteristics sections of the
specification is not implied. Exposure to limiting values for extended periods
may affect device reliability.
Application information — Applications that are described herein for any
of these products are for illustrative purposes only. Philips Semiconductors
make no representation or warranty that such applications will be suitable for
the specified use without further testing or modification.
Right to make changes — Philips Semiconductors reserves the right to
make changes in the products - including circuits, standard cells, and/or
software - described or contained herein in order to improve design and/or
performance. When the product is in full production (status ‘Production’),
relevant changes will be communicated via a Customer Product/Process
Change Notification (CPCN). Philips Semiconductors assumes no
responsibility or liability for the use of any of these products, conveys no
licence or title under any patent, copyright, or mask work right to these
products, and makes no representations or warranties that these products are
free from patent, copyright, or mask work right infringement, unless otherwise
specified.
Contact information
For additional information, please visit http://www.semiconductors.philips.com.
For sales office addresses, send e-mail to: [email protected].
Product data
Fax: +31 40 27 24825
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
9397 750 10904
Rev. 02 — 21 February 2003
18 of 19
Philips Semiconductors
PIP250M
Integrated buck converter
Contents
1
2
3
4
5
6
6.1
6.2
7
7.1
7.1.1
7.1.2
7.1.3
7.1.4
7.1.5
7.1.6
7.1.7
7.2
7.2.1
7.2.2
7.2.3
7.2.4
7.2.5
7.2.6
8
9
10
11
12
13
14
14.1
14.2
15
15.1
15.2
16
17
18
19
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Ordering information . . . . . . . . . . . . . . . . . . . . . 1
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Pinning information . . . . . . . . . . . . . . . . . . . . . . 3
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 3
Functional description . . . . . . . . . . . . . . . . . . . 4
Pin functions . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Output stage supply (VDDO, VSSO) . . . . . . . . . . 4
Output voltage (VO) . . . . . . . . . . . . . . . . . . . . . 4
Control circuit supply (VDDC, VSSC) . . . . . . . . . . 4
Bootstrap capacitor connection (CB) . . . . . . . . 4
Voltage feedback pin (FB). . . . . . . . . . . . . . . . . 4
Current limit set and enable
input (OCSET/ENABLE) . . . . . . . . . . . . . . . . . 4
Sense connection for current limit (PHASE) . . . 4
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Single supply operation . . . . . . . . . . . . . . . . . . 5
Regulated output voltage . . . . . . . . . . . . . . . . . 5
Power on reset . . . . . . . . . . . . . . . . . . . . . . . . . 5
Soft start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Overcurrent protection . . . . . . . . . . . . . . . . . . . 6
Undervoltage and overvoltage protection . . . . . 7
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 8
Thermal characteristics. . . . . . . . . . . . . . . . . . . 9
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Application information. . . . . . . . . . . . . . . . . . 11
Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 13
Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Introduction to soldering HVQFN packages . . 14
Rework guidelines . . . . . . . . . . . . . . . . . . . . . 15
Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
PCB design guidelines . . . . . . . . . . . . . . . . . . 15
Solder paste printing. . . . . . . . . . . . . . . . . . . . 16
Revision history . . . . . . . . . . . . . . . . . . . . . . . . 17
Data sheet status . . . . . . . . . . . . . . . . . . . . . . . 18
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
© Koninklijke Philips Electronics N.V. 2003.
Printed in The Netherlands
All rights are reserved. Reproduction in whole or in part is prohibited without the prior
written consent of the copyright owner.
The information presented in this document does not form part of any quotation or
contract, is believed to be accurate and reliable and may be changed without notice. No
liability will be accepted by the publisher for any consequence of its use. Publication
thereof does not convey nor imply any license under patent- or other industrial or
intellectual property rights.
Date of release: 21 February 2003
Document order number: 9397 750 10904