SP6652ER-L Exar Corporation, SP6652ER-L Datasheet - Page 9

• Manufacturer Part Number: SP6652ER-L
• Description: IC PWM BUCK CURRENT MODE 10DFN
• Manufacturer: Exar Corporation
• Type: Step-Down (Buck)r

Specifications of SP6652ER-L

• Package / Case: 10-VFDFN Exposed Pad
• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 0.9 V ~ 5 V
• Current - Output: 1A
• Frequency - Switching: 1.4MHz
• Voltage - Input: 2.85 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: *
• Output Voltage: Adjustable
• Output Current: 1 A
• Input Voltage: 2.85 V to 5.5 V
• Mounting Style: SMD/SMT
• Duty Cycle (max): 100 %
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 1016-1216

The output voltage can be set using the
formula:
V
Where V
T
T
Compensation Component Selection
For simplicity in compensation with ce-
ramic output capacitors, the SP6652 uses
current mode PWM control, so all that is
needed for stability is a series R
at the COMP pin to compensate the error
amplifier. To see the actual SP6652 re-
sponse with frequency, in figure 3 we have
taken a bode plot of gain and frequency re-
sponse of the SP6652 circuit with 3.3Vout.
Looking first at the SP6652 Modulator Gain
at low frequency you see a constant gain
of about 26dB and the first pole or -3dB
point at about 4 kHz, where the slope of
the gain curve becomes about -20dB/de-
cade. At high frequency on the SP6652
Modulator Gain curve one can see the
modulator curve slope increase down-
Table 1. Capacitor Selection
Oct10-07 RevJ
on
on
OUT
Murata/www.murata.com
Table 2. Inductor Selection
Manufacturers/ Website
Murata/www.murata.com
Murata/www.murata.com
(
min
is kept within 200nsec Minimum:
Wurth Elektronik/ www.we-online.de
TDK/www.tdk.com
TDK/www.tdk.com
TDK/www.tdk.com
= V
Wurth Elektronik/ www.we-online.de
)
= V
Sumida/ www.sumida.com
Sumida/ www.sumida.com
FB
The range of typical inductor values and sizes are shown here in Table 2.
Manufacturers/ Website
FB
Coilcraft/ www.coilcraft
Coilcraft/ www.coilcraft
*( + R
= 0.8V typically, and for no-load
OUT
/(V
IN
F
/R
*Freq).
I
)
SP6652 1A, High Efficiency, Current Mode PWM Buck Regulator
GRM21BR60J106KE19L
GRM155R60J105KE19B
GRM188R60J475KE19
C1005X5R0J105M
C2012X5R0J106M
C1608X5R0J475K
Part Number
Note: Component highlighted in bold is used on the SP6652EB Evaluation Board.
Note: Component highlighted in bold is used on the SP6652EB Evaluation Board.
Z
WE-TPC #744042003
WE-TPC #744042004
and C
MSS5131-332MX
MSS5131-332MX
CDRH3D28-3R3
CDRH3D28-4R7
Part Number
C
9
-10
-20
-30
-40
-50
-60
60
50
40
30
20
10
ward for a high frequency pole at about
150KHz, which is widely separated in
frequency from the low frequency 4kHz
pole, so that the SP6652 can be compen-
sated by a zero at the low frequency pole
where the gain slope is only -20dB/decade.
The gain for the error amplifier is the cross-
0
Figure 3. SP6652 Gain and Frequency
Response 3.3V output voltage
Capacitance/
100
4.7uF/6.3V
4.7uF/6.3V
10uF/6.3V
10uF/6.3V
1uF/6.3V
1uF/6.3V
Voltage
Inductance/ Isat
SP6652 Loop Gain
SP6652 Modulator Gain
SP6652 Loop Phase
SP6652 Modulator Phase
4.7uH/1.65A
4.7uH/1.65A
3.3uH/1.6A
4.7uH/1.4A
3.3uH/2.0A
3.3uH/1.8A
Rating
3.3Vout
Rz = 4K Ω
Cc = 10nF
pole1 -3dB
at 4kHz
APPLICATIONS INFORMATION
1000
SP6652 Bode Plot
Size/Type/Thickness
0805/X5R/1.35mm
0805/X5R/1.35mm
0402/X5R/0.55mm
0402/X5R/0.5mm
0603/X5R/0.9mm
0603/X5R/0.9mm
Length/Width/Thickness
10000
-20dB/dec
Capacitor
5.1x5.1x3.1mm
5.1x5.1x3.1mm
4.0x4.0x3.0mm
4.0x4.0x3.0mm
4.8/4.8/1.8mm
4.8/4.8/1.8mm
Inductor
A t 0dB Loop Gain
Fo = 80kHz
Loop Phase = 50deg
© 2007 Sipex Corporation
100000
Frequency
Log
.
100KHz
ESR at
DCR Max
1000000
0.03
0.02
0.02
0.03
0.02
0.02
ohms
0.032
0.045
0.058
0.071
0.065
0.082
180
150
120
90
60
30
0
-30
-60
-90
-120
-150
-180
(Hz)