DC1395A - Demo Manual

QUICK START GUIDE FOR
LT3505EDD
DC1395A
LT3505EDD: PMIC High Voltage
Adaptor Board with 5 Volt Adaptor Inputs
DESCRIPTION
Demonstration Circuit 1395A is a 1.2A, Step-Down
Switching Regulator in a 3mm × 3mm DFN. The
LT3505EDD is available in an 8-pin (3mm × 3mm)
DFN surface mount package.
L, LTC, LTM, LT, Burst Mode, OPTI-LOOP, Over-The-Top and PolyPhase are registered
trademarks of Linear Technology Corporation. Adaptive Power, C-Load, DirectSense, Easy
Drive, FilterCAD, Hot Swap, LinearView, μModule, Micropower SwitcherCAD, Multimode
Dimming, No Latency ΔΣ, No Latency Delta-Sigma, No RSENSE, Operational Filter, PanelProtect,
PowerPath, PowerSOT, SmartStart, SoftSpan, Stage Shedding, SwitcherCAD, ThinSOT,
UltraFast and VLDO are trademarks of Linear Technology Corporation. Other product names
may be trademarks of the companies that manufacture the products.
PERFORMANCE SUMMARY Specifications are at TA = 25°C
SYMBOL
HVIN
5V ADAPTOR
HVBUCK
IHVBUCK
PARAMETER
High Voltage Input Voltage Range
5V Adaptor Input Voltage Range
Output Voltage Range
Output Current
CONDITIONS
Input disabled from 36-40V
Range is mode and load dependant
QUICK START PROCEDURE
MIN
8
4.5
3.5
TYP
MAX
40
5.5
5.5
2
UNITS
V
V
V
A
LTC4098EPDC on the DC1303A board has connected HVBUCK to VOUT.
Using short twisted pair leads for any power connections, with all loads and power supplies off, refer
to Figures 1 & 2 for the proper measurement and
equipment setup.
3. Set Load1 to 1A. Observe that 4.35V < VOUT
(VM3) 4.55V. Set Load1 to 0A. The 1A load on
VOUT loads HVBUCK, so the LT3505EDD is
supplying 1A.
A companion PMIC demo board is required for this
check out procedure. The DC1303A
(LTC4098EPDC) board is recommended, and will be
used for the following procedure. Please refer to
the DC1303A Quick Start Guide for further information.
4. Set PS1 to 36V. Observe that 4.50V < VOUT
(VM3) < 4.70V. The LT3505 is designed to operate from HVIN = 8V to 36V.
Follow the procedure below:
6. Set “COMP” jumper (JP2) to “REMOTE”. Observe that 3.80V < VOUT (VM3) < 4.10V. The
LTC4098EPDC is now controlling the LT3505
output voltage to approximately V(BAT) + 0.3V.
1. Set PS1 to 8V, PS2 to 0V, and PS3 to 3.6V. Set
Load1 to 0A. Ensure that jumpers are configured as per Figure 1, except the “D2” jumper
(JP3) on the DC1303A should be set to “1”.
2. Observe that 4.50V < VOUT (VM3) < 4.70V. The
LT3480 HV Buck regulator is running with its
control loop closed locally. The nominal
HVBUCK voltage is 4.75V, and the
1
5. Set Load1 to 1A. Observe that 4.20V < VOUT
(VM3) < 4.55V. Set Load1 to 0A. The LT3505
is now supplying 1A, while operating from 38V.
7. Set Load1 to 1A. Observe that 3.70V < VOUT
(VM3) < 3.90V. Set Load1 to 0A. LT3505 is
supplying 1A, while under LTC4098 control.
8. Set PS1 to 8V. Observe that 3.80V < VOUT
(VM3) < 4.10V.
LT3505EDD
9. Set Load1 to 1A. Observe that 3.70V < (VM3) <
3.90V. Set Load1 to 0A.
10. Set PS2 to 4.5V, and “WALL” jumper (JP3) to
“5V ADAPTOR”. Observe that 4.40 < VOUT
(VM3) < 4.50V. The LT3505 is not supplying
power to VOUT. This verifies that the LTC4098
recognizes the 5V Adaptor input, and connects it
to VOUT.
11. Set Load1 to 1A. Observe that 4.10V < VOUT
(VM3) < 4.40V. Set Load1 to 0A.
12. Set PS2 to 5.5V. Observe that 5.40V < VOUT
(VM3) < 5.50V.
13. Set Load1 to 1A. Observe that 5.10V < VOUT
(VM3) < 5.50V.
2
LT3505EDD
-
+
PS1
+
0V-40V supply
1A
-
VM1
-
+
PS2
+
0V-6V supply
2A
-
+
AM1
AM2
+
VM2
-
D2
D1
D0
AM3
-
+
+
+
VM3
-
-
Load 1
0V-5V
5A
AM4
+
-
+
VM4
-
3.6Ω
+
-
VM6
Note: All connections from equipment should be Kelvin connected directly to the Board PINS which they are connected to on this diagram and any input, or output, leads should be twisted pair
Figure 1. Proper Measurement Equipment Setup for DC1395A
GND
VIN
Figure 2. Measuring Input or Output Ripple
3
PS3
0V-5V supply
2A
LT3505EDD
Figure 3. DC1395A Schematic
4
LT3505EDD
Figure 4. DC1395A BOM
5
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