DC1396A - Demo Manual

QUICK START GUIDE FOR
LTC4099EPDC
DC1396A
LTC4099EPDC: High
Efficiency I2C Controlled USB
Power Manager/Charger with Overvoltage Protection
DESCRIPTION
Demonstration Circuit 1396A is a high efficiency USB
Power/Li-Ion battery manager plus a HV regulator battery tracking controller. The LTC4099EPDC is available in a 20-pin (3mm × 4mm × 0.55mm) UTQFN 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
VUSB
VOUT
VBAT
IBAT
PARAMETER
VUSB Input Voltage Range
VOUT Output Voltage Range
Output Float Voltage
Output Charge Current
CONDITIONS
Input disabled from 6V–30V
Range is mode and load dependant
Constant voltage mode
Constant current mode
SOFTWARE GUI
The DC1396A Demo Circuit can be controlled from a
software GUI. This software GUI is necessary to control many functions of the LTC4099. In addition, a
DC590 board is necessary to connect the DC1396A to
the PC. For proper testing of the Production Dem O
Circuits, the Beta version or the released version of the
QuickEval installation program should be used to load
the DC1396 GUI. This is a screen shot of the GUI:
MIN
4.35
3.5
TYP
4.2
0.5
MAX
5.5
5.5
1
UNITS
V
V
V
A
The GUI, along with R8 and R9, allows complete
configuration of the functionality of the LTC4099.
The input current limit, charge current, float voltage,
C/x threshold, thermal regulation temperature, and
safety timer period can be programmed. The battery charger and battery conditioner can be turned
on and off.
The internal status word can be read back, and the
conditions which cause an interrupt can be set.
The GUI will remember most functions from session to
session, and can be set to defaults with a single button
push.
Input Current Limit
The input current limit can be set to one of eight levels,
determined by the CLPROG (R9) resistor. The value of
the eight levels is computed dynamically if the resistor
value is edited. The resistor value is remembered, if
the save values button is active. The value of the
CLPROG resistor in in kΩ.
Figure 1: LTC4099 GUI screenshot
1
Charge current
The battery charge current can be set to one of eight
levels determined by the PROG (R8) resistor. The of
LTC4099EPDC
the eight levels is computed dynamically if the resistor
value is edited. The resistor value is remembered, if
the save values button is active. The value of the
PROG resistor is in kΩ.
Interrupt generation
The conditions that cause an interrupt can be controlled. Please note that interrupts are generated on
any change in the enabled conditions.
For example, if “USB Good” is enabled, then an interrupt will be generated for both USB voltage becoming
valid and for USB voltage becoming invalid.
Status readback
The status readback can be set to readback automatically at the interval in the “Update Interval” input box.
This defaults to 100ms.
Register display
The command registers values sent over the I2C are
displayed, as well as the currently readback status values. This is a programming aid.
2
LTC4099EPDC
QUICK START PROCEDURE
Using short twisted pair leads for any power connections, with all loads and power supplies off, refer
to Figures 2 & 3 for the proper measurement and
equipment setup.
A companion HV Buck demo board is required for
this check out procedure. The DC1394 (LT3480)
board is recommended, and will be used for the following procedure. Please refer to the DC1394 Quick
Start Guide for further information.
Please note that the following procedure assumes
that the default values of the GUI, R8, and R9.
Follow the procedure below:
1. Set PS1 to 5V, and PS4 to 3.6V. Start LTC4099
GUI. Observe VOUT (VM5), I (VUSB) (AM1),
V(CLPROG) (VM4) and V(PROG) (VM7). The
LTC4099 defaults to 100mA input current limit
and 500mA battery charger current. Since the
battery current exceeds the current available
from the USB port, VOUT collapses to nearly the
battery voltage of 3.6V.
4. Set Ld1 to 0, and use the GUI to set charge current to 900mA. Observe VOUT(VM5), I(VUSB)
(AM1), V(CLPROG) (VM4) and V(PROG) (VM7).
5. Set DC1395 “WALL” jumper (JP3) to
“HVBUCK”, “COMP” jumper (JP2) to “EXT”, and
“SYNC” jumper (JP1) to “PWM/SYNC”. Turn
on PS2 and set to 8V. Observe VOUT (VM5),
I(VUSB) (AM1) and V(PROG) (VM7). The HV
Buck regulator on the LT3480 board is now
powering VOUT. Availability of this voltage is
detected on the WALL pin, and this shuts down
the VOUT buck regulator on the LTC4099, while
enabling the VC pin to control the output voltage
on VOUT. This preserves the Bat-Track feature,
even when using an external HV Buck regulator.
6. Turn on PS2 and set to 32V. Observe VOUT
(VM5), I(VUSB) (AM1) and V(PROG) (VM7).
7. Use to automatic readback of status, and to assert an interrupt on change of “WALL” input
status. Turn off PS2. Did /IRQ LED light? Does
GUI show interrupt? Clear interrupt in GUI. The
interrupt generator has been set to generate an
interrupt on any change on the validity of the
voltage present on the WALL pin.
2. Use the GUI to set the input current limit to
1000mA. Observe VOUT (VM5), I (VUSB)
(AM1), V(CLPROG) (VM4) and V(PROG) (VM7).
The input current limit is now greater that the
battery charge current, so VOUT rises to V(BAT)
+ 0.3V, or 3.9V.
8.
3. Use the GUI to set the input current limit o
1260mA. Set Ld1 to 1A. Observe VOUT (VM5),
I(VUSB) (AM1), V(CLPROG) (VM4) and
V(PROG) (VM7). The input current limit is sufficient to supply 1.5 amps, Ld1 current plus battery charger current of 0.5A, and VOUT is 3.9V.
1260mA input current limit is sufficient due to
the transformer action of the VOUT regulator,
which exchanges output voltage for output current.
9. Set PS1 to 0V, and Ld1 to 0A. Observe VOUT
(VM5) and V (VOUT, BAT) (VM5 – VM6). The
Ideal Diode is on and powers VOUT from V
(BAT).
3
Move “NTC” jumper (JP1) to EXT. Did GUI
show “Battery too cold”? Did /IRQ LED light?
The status byte is reporting that the NTC temperature measurement indicated that battery
was too cold. However, no interrupt was generated because the NTC interrupt wasn’t enabled.
10. Set Ld1 to 1A. Observe VOUT (VM5) and V
(VOUT, BAT) (VM5-VM6). Set Ld1 to 0A.
11. Increase PS4, until GUI status indicates
charger is in constant voltage mode. Observe
V (BAT) (VM6).
LTC4099EPDC
12. Decrease PS4, until GUI indicates charger is in
constant current mode. Observe V (BAT)
(VM6).
13. Use GUI to set float voltage to 4.2V. Increase
PS4, until GUI status indicates charger in constant voltage mode. Observe V (BAT) (VM6).
14. Decrease PS4, until GUI indicates charger is in
constant current mode. Observe V (BAT)
(VM6).
15. Set PS3 to 5V, set WALL (DC1394, JP3) to “5V
ADAPTOR” and PS3 to 5V. Observe VOUT
(VM6) and V (PROG) (VM5).
4
LTC4099EPDC
-
+
PS2
+
0V-40V supply
1A
-
VM2
-
+
PS3
+
0V-6V supply
2A
-
+
AM2
+
AM3
VM3
+
VM4
-
CLPROG
AM4
+
+
+
VM5
-
-
Load1
0V-5V
5A
AM1
+
+
PS1
+
0V-6V supply
2A
-
+
AM5
-
0.5A-1.2A
+
VM1
VM6
-
-
+
-
+
3.6Ω
+
-
PS4
0V-5V supply
2A
VM7
VM8
+
-
VM9
14 pin ribbon
cable
Linear Technology
DC590B USB to I2C
converter
USB
cable
PC running
LTC4099 demonstration software
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 2. Proper Measurement Equipment Setup for DC1396A
GND
VIN
Figure 3. Measuring Input or Output Ripple
5
LTC4099EPDC
Figure 4. DC1396A Schematic
6
LTC4099EPDC
Figure 5. DC1396A BOM
7
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