Linear Technology 1394A Quick Start Manual

DESCRIPTION
Demonstration Circuit 1394A is a 38V, 2A, 2.4MHz
Step-Down Switching Regulator with 70μA Quiescent
Current. The LT3480EDD is available in a 10-pin
(3mm × 3mm) DFN surface mount package.
PERFORMANCE SUMMARY
SYMBOL PARAMETER
HVIN High Voltage Input Voltage Range
5V ADAPTOR 5V Adaptor Input Voltage Range
HVBUCK Output Voltage Range
I Output Current
HVBUCK
QUICK START PROCEDURE
Using short twisted pair leads for any power
connections, with all loads and power supplies
off, refer to Figures 1 & 2 for the proper meas-
urement and equipment setup.
A companion PMIC demo board is required for
this check out procedure.
(LTC4098EPDC) board is recommended, and
will be used for the following procedure.
Please refer to the DC1303A Quick Start
Guide for further information.
Follow the procedure below:
1. Set PS1 to 8V, PS2 to 0V, and PS3 to
3.6V. Set Load1 to 0A. Ensure that jump-
ers are configured as per Figure 1, except
the "D2" jumper (JP3) on the DC1303A
should be set to "1".
2. Observe that 4.60V < VOUT (VM3) <
4.80V. The LT3480 HV Buck regulator is
running with its control loop closed locally.
The nominal HVBUCK voltage is 4.75V,
and the LTC4098EPDC on the DC1303A
board has connected HVBUCK to VOUT.
1
PMIC High Voltage Adaptor Board
L
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 R
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.
Specifications are at T
CONDITIONS
Input disabled from 38-60V
Range is mode and load dependant
The DC1303A
QUICK START GUIDE FOR
With 5V Adaptor Inputs
, LTC, LTM, LT, Burst Mode, OPTI-LOOP, Over-The-Top and PolyPhase are registered
= 25°C
A
3. Set Load1 to 2A. Observe that 4.60V <
VOUT (VM3) 4.80V. Set Load1 to 0A.
The 2A load on VOUT loads HVBUCK, so
the LT3480EDD is supplying 2A.
4. Set PS1 to 38V. Observe that 4.60V <
VOUT (VM3) < 4.80V. The LT3480 is de-
signed to operate from HVIN = 8V to 38V.
5. Set Load1 to 2A. Observe that 4.60V <
VOUT (VM3) < 4.80V. Set Load1 to 0A.
The LT3480 is now supplying 2A, while
operating from 38V.
6. Set "COMP" jumper (JP2) to "REMOTE".
Observe that 3.80V < VOUT (VM3) <
4.10V. The LTC4098EPDC is now control-
ling the LT3480 output voltage to approxi-
mately V(BAT) + 0.3V.
7. Set Load1 to 2A. Observe that 3.80V <
VOUT (VM3) < 4.10V. Set Load1 to 0A.
LT3480 is supplying 2A, while under
LTC4098 control.
8. Set PS1 to 8V.
VOUT (VM3) < 4.10V.
DC1394A
, Operational Filter, PanelProtect,
SENSE
MIN TYP MAX UNITS
8 60
4.5 5.5
3.5 5.5
2
Observe that 3.80V <
V
V
V
A