Rainbow Electronics MAX8707 - Manual (Page 10)

MAX8707
Multiphase, Fixed-Frequency Controller for
AMD Hammer CPU Core Power Supplies
10 ______________________________________________________________________________________
Typical Operating Characteristics
(Circuit of Figure 1. V
IN
= 12V, V
CC
= 5V, SUS = SKIP = GND, SHDN = V
CC
, V
SUSV
= 0.80V, T
A
= +25°C, unless otherwise specified.)
OUTPUT OFFSET VOLTAGE
DISTRIBUTION
MAX8707 toc10
OUTPUT OFFSET VOLTAGE (mV)
SAMPLE PERCENTAGE (%)
1 -1 -3
10
20
30
40
50
0
-5 5 3
SAMPLE SIZE = 100
1.550V
0.800V
VPS TRANSCONDUCTANCE
DISTRIBUTION
MAX8707 toc11
TRANSCONDUCTANCE ( µS)
SAMPLE PERCENTAGE (%)
203 201 199 197
10
20
30
40
50
60
70
0
195 205
SAMPLE SIZE = 100
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0 5 10 15 20 25
CURRENT-SENSE VOLTAGE DIFFERENCE
vs. LOAD CURRENT
MAX8707 toc12
LOAD CURRENT (A)
CURRENT-SENSE DIFFERENCE (mV)
STARTUP WAVEFORM
(NO LOAD)
MAX8707 toc13
A. SHDN, 5V/div
B. DRSKP, 10V/div
C. REF, 2V/div
D. OUT, 1V/div E. VROK, 10V/div
F. DL1, 10V/div
G. INDUCTOR CURRENT
(I
L1 ), 10A/div
200 µs/div
0
0
3.3V A
B
C
D
E
F
G
0
0
5V
2V
1V
STARTUP WAVEFORM
(20A LOAD)
MAX8707 toc14
A. SHDN, 5V/div
B. DRSKP, 10V/div
C. REF, 2V/div
D. OUT, 1V/div E. VROK, 10V/div
F. DL1, 10V/div
G. INDUCTOR CURRENT
(I
L1
), 10A/div
200 µs/div
0
0
3.3V
A
B
C
D
E
F
G
0
0
5V
2V
1V
SHUTDOWN WAVEFORM
(NO LOAD)
MAX8707 toc15
A. SHDN, 5V/div
B VROK, 10V/div
C. OUT, 1V/div D. DL1, 10V/div
E. INDUCTOR CURRENT
(I
L1 ), 10A/div
200 µs/div
0
0
3.3V
A
B
C
D
E
0
0
5V
1.3V