Kingbor Technology Co.,Ltd
TEL:(86)0755-26508846 FAX:(86)0755-26509052
kB3440
TYPICAL APPLICATION
Efficiency of the WCDMA
Power Amp Power Supply
WCDMA Power Amp Power Supply with Dynamic Voltage Control
V
= 3.3V – 1.7V • (V
– 1.22V)
DAC
100
98
96
94
92
90
88
86
84
82
80
OUT
V
= 3.4V
OUT
DAC
L1
3.3µH
D1**
V
OUT
0.4V TO 5V
I
= 100mA
OUT
C3
3
7
8
2
1
4
33pF
SW1
SW2
kB3440
V
= 2.5V TO 4.2V
I
= 250mA
R1
340k
R5
10k
IN
OUT
6
V
V
IN
OUT
FB
R6
200k
9
SHDN/SS
I
= 600mA
OUT
C4 150pF
R3 15k
10
5
+
C1
10µF
MODE/SYNC
V
C
*
Li-Ion
C2**
10µF
R2
R
T
GND
= 2MHz
200k
C5 10pF
R
T
f
OSC
30.1k
2.5
3
3.5
4
4.5
5
INPUT VOLTAGE (V)
*1 = Burst Mode OPERATION
0 = FIXED FREQUENCY
** LOCATE COMPONENTS AS
CLOSE TO IC AS POSSIBLE
C1, C2: TAIYO YUDEN JMK212BJ106MM
D1: ON SEMICONDUCTOR MBRM120T3
L1: SUMIDA CDRH4D28-3R3
GSM Modem Powered from USB or PCMCIA with 500mA Input Current Limit
L1
10µH
V
OUT
3.6V
2A
(PULSED)
3
7
8
2
1
4
SW1
kB3440
SW2
R
S
R1
V
IN
0.11
392k
6
2.5V TO 5.5V
USB/PCMCIA POWER
500mA MAX
V
V
IN
OUT
FB
R6
130k
+
–
1N914
C6 TO C9
470µF
×4
9
SHDN/SS
1/2 LT1490A
10
5
MODE/SYNC
V
C
*
C1
10µF
R2
200k
C5
10nF
R
GND
T
R
T
R5
24k
60.4k
C1: TAIYO YUDEN JMK212BJ106MG
C2: TAIYO YUDEN JMK325BJ226MM
L1: SUMIDA CDRH-4D28-100
*1 = Burst Mode OPERATION
0 = FIXED FREQUENCY
+
R4
1k
2N3906
1/2 LT1490A
–
1.22 • R4
=
I
CURRENTLIMIT
R5 • R
S
17
KINGBOR [ KINGBOR TECHNOLOGY CO ]
