DC544A - Demo Manual

QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 544
MICROPOWER STEP-DOWN SWITCHING REGULATOR IN THINSOT
LT1934ES6
DESCRIPTION
Demonstration circuit 544 features the LT1934 and
LT1934-1 wide input range micro power step-down
switching regulators. There are two switching regulator circuits in DC544, the LT1934ES6 circuit designed
to convert 4.5V~34V input to 3.3V at 250mA output
and the LT1934ES6-1 circuit designed for the same
input and output voltage at 50mA load current.
Each circuit has two jumpers for testing SHDN mode
operation and selecting the output voltage setting
(3.3V or 5V). Placing the jumper (JP1 & JP3) to “RUN”
enables LT1934 step down converter operation and
placing the jumper to “SHDN” disables the LT1934 and
the circuit will turn off. The output voltage jumper (JP2
& JP4) changes the feedback resistor value to change
the output voltage. Placing the jumper at “3.3V” sets
the output to 3.3V and placing the jumper at “5V” sets
the output voltage to 5V. For 5V output operation, the
input voltage range needs to be 6.5V ~34V.
The aluminum electrolytic input capacitor is used at the
input for damping the voltage overshoot ringing caused
by a low impedance voltage source and a long input
power cable (LC tank). See Application Note 88 for
more details.
Design files for this circuit board are available. Call
the LTC factory.
Table 1. Performance Summary
PARAMETER
CONDITION
VALUE
Minimum Input Voltage
For 3.3V output, 6.5V Min. for 5V output
4.5V
Maximum Input Voltage
Maximum Output Current
34V
4.5V~34V input to 3.3V output
VOUT REG
250mA
≅ 60mV
QUICK START PROCEDURE
UPPER CIRCUIT (BOOST CONVERTER)
Refer to Figure 1 for proper measurement equipment
setup and follow the procedure below:
1. Connect the input power supply (set at 7V initially) to the Vin and GND pins.
2. Turn on the input power supply and observe the
output voltage. The output voltage should read
3.3V ± 0.06V.
3. Test the SHDN function by moving the JP1
jumper from RUN to SHDN (turn on the load box
preset at 250mA for a few seconds to discharge
the output capacitor). The output should read
0V.
4. Return the jumper back to RUN. The output voltage should now read 3.3V ± 0.06V.
5. Turn on the load box preset at 250mA. The input current should read ≅ 150mA and the output
voltage should be 3.3V ± 0.06V.
6. Slowly change the input power supply voltage
from 4.5V to 34V while observing the output
voltage.
The output should stay within
3.3V ± 0.06V.
7. Observe the input current at 34V, it should read
≅ 35mA.
8. Change the input power supply voltage back to
7V and check the output ripple using the oscilloscope. The output ripple should not be higher
than 50mV. Also check the switching frequency.
The period should be 3uS.
1
QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 544
MICROPOWER STEP-DOWN SWITCHING REGULATOR IN THINSOT
LOWER CIRCUIT (BOOST CONVERTER)
Refer to Figure 1 for proper measurement equipment
setup and follow the procedure below:
1. Connect the input power supply (set at 7V initially) to the Vin and GND pins.
2. Turn on the input power supply and observe the
output voltage. The output voltage should read
3.3V ± 0.06V.
3. Test the SHDN function by moving the JP1
jumper from RUN to SHDN (turn on the load box
preset at 50mA for a few seconds to discharge
the output capacitor). The output should read
0V.
4. Return the jumper back to RUN. The output voltage should read 3.3V ± 0.06V.
5. Turn on the load box preset at 50mA. The input
current should read ≅ 30mA and the output voltage should be 3.3V ± 0.06V.
6. Slowly change the input power supply voltage
from 4.5V to 34V while observing the output
voltage.
The output should stay within
3.3V ± 0.06V.
7. Observe the input current at 34V, it should read
≅ 10mA.
8. Change the input power supply voltage back to
7V and check the output ripple using the oscilloscope. The output ripple should not be higher
than 40mV. Also check the switching frequency.
The period should be 3uS.
2
QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 544
MICROPOWER STEP-DOWN SWITCHING REGULATOR IN THINSOT
3
5
4
3
2
1
D1
U1
LT1934ES6 1
Vin
4.5V to 34V
1N4148WS
C1
0.22uF
BOOST
5
D
1
E1
RUN
2
4
SHDN
C3
2.2uF
6
SHDN
FB
3
L1
47uH
E2
D
R1
C2
634K 10pF
+ C5
68uF
6.3V
POSCAP
GND
2
D2
B0540W
R2
383K
R3
464K
1
C4
10uF
SW
R4
511K
3
+
JP1
VIN
Vout
[email protected]
[email protected]
5V
3.3V
JP2
2
GND
3
GND
C
E4
E3
C
D3
U2
LT1934ES6-1 1
Vin
4.5V to 34V
BOOST
5
RUN
B
2
4
SHDN
C8
10uF
C9
1.0uF
SW
6
FB
3
R7
511K
SHDN
150uH
E6
R9
C7
634K 10pF
+ C10
68uF
6.3V
POSCAP
GND
3
+
JP3
VIN
Vout
[email protected]
[email protected]
2
D4
B0540W
R11
383K
R10
464K
B
1
1
E5
1N4148WS
C11
0.22uF
L2
JP4
5V
3.3V
2
GND
3
GND
E7
E8
CONTRACT NO.
APPROVALS
A
DRAWN
DATE
June Wu
6/10/02
Dave Kim
6/10/02
CHECKED
TECHNOLOGY
TITLE
A
LT1934ES6/LT1934ES6-1
Micropower Step-Down Switching Regulators in ThinSOT
APPROVED
ENGINEER
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
DESIGNER
SIZE CAGE CODE
DWG NO
REV
A
DEMO CIRCUIT 544A
Thursday, December 12, 2002
5
4
3
SCALE:
2
FILENAME:
SHEET
1
1
OF
1
Bill Of Material
Demo Bd. #544A
Linear Technology Corporation
LT1934ES6/ LT1934ES6-1
6/17/2005
Item Qty Reference
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
2
2
1
1
2
2
2
2
8
4
4
1
1
2
2
2
2
1
1
1
C11,C1
C2,C7
C3
C9
C4,C8
C5,C10
D1,D3
D2,D4
E1-E8
JP1-JP4
JP1-JP4
L1
L2
R1,R9
R2,R11
R3,R10
R7,R4
U1
U2
Part Description
CAP., X7R, 0.22uF, 10V, 20% 0603
CAP., C0G, 10pF, 50V, 10% 0402
CAP., X5R, 2.2uF, 35V, 20% 1210
CAP., X5R, 1.0uF, 35V, 20% 1206
CAP., Aluminum, 10uF, 35V 5X6.0
CAP., POSCAP, 68uF, 6.3V B2 SIZE
DIODE, 1N4148WS,
SOD-323
Schottky Barrier REC., B0540W, SOD-123
TESTPOINT, TURRET, .094"
0.079 SINGLE ROW HEADER, 3PIN
SHUNT,
INDUCTOR, 47uH,
CDH4D28
INDUCTOR, 150uH,
DO1608
RES., CHIP, 634K, 1/16W, 1% 0402
RES., CHIP, 383K, 1/16W, 1% 0402
RES., CHIP, 464K, 1/16W, 1% 0402
RES., CHIP, 511K, 1/10W, 1% 0805
I.C. LT1934ES6,
Thin SOT23-6
I.C. LT1934ES6-1,
Thin SOT23-6
PRINTED CIRCUIT BOARD
Page 1 - of - 1
Manufacture / Part #
AVX, 0603ZC224MAT2A
AVX, 04025A100KAT2A
Taiyo Yuden, GMK325BJ225MN
Taiyo Yuden, GMK316BJ105ML
SANYO, 35CV10AX
SANYO, 6TPB68M
DIODES INC., 1N4148WS-7
DIODES INC., B0540W-7
MILL-MAX, 2501-2
COMM CON, 2802S-03-G1
COMM CON, CCIJ2MM-138G
SUMIDA, CDRH4D28-470
COILCRAFT, DO1608C-154
AAC, CR05-6343FM
AAC, CR05-3833FM
AAC, CR05-4643FM
AAC, CR10-5113FM
LINEAR, LT1934ES6
LINEAR, LT1934ES6-1
DEMO CIRCUIT #544A
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