EVAL6920DB1 STMicroelectronics, EVAL6920DB1 Datasheet - Page 5

• Manufacturer Part Number: EVAL6920DB1
• Description: EVAL BOARD FOR L6920DB
• Manufacturer: STMicroelectronics
• Type: DC/DC Switching Converters, Regulators & Controllersr

Specifications of EVAL6920DB1

• Main Purpose: DC/DC, Step Up
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 3.3V or 5V
• Current - Output: 100 ~ 400mA
• Voltage - Input: 0.8 ~ 3.6 V
• Regulator Topology: Boost
• Frequency - Switching: 1MHz
• Board Type: Fully Populated
• Utilized Ic / Part: L6920
• Input Voltage: 0.6 V
• Output Voltage: 1.8 V
• Dimensions: 17.5 mm to 12.6 mm
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: L6920DB
• Other names: 497-5503

AN2206
1.4
1.5
1.6
Table 2.
Inductor selection
Usually, inductors ranging between 2 µH to 10 µH satisfy most application requirements.
However, small-value inductors are physically smaller and guarantee a faster response to
load transients.
Inductor size also affects the maximum current deliverable to the load. A low series
resistance is suggested if very high efficiency values are needed. In any case, the saturation
current of the choke should be higher than the peak current limit of the device (800 mA typ.).
Good surface-mount inductors are available from COILCRAFTS, COILTRONICS and other
sources (see
Table 3.
Switching frequency
The control loop of the L6920DB is based on a Minimum OFF-time and a Maximum ON-time
(see datasheet). This means that the switching frequency is not fixed, but changes in order
to keep the output voltage regulated. The maximum reachable value is approximately 1MHz.
The frequency value depends on the inductor value, input and output voltage, and the load.
Low battery detection
The L6920DB includes a low battery detection comparator. The threshold is V
and a hysteresis is added to avoid oscillations when input crosses the threshold slowly. The
Low Battery Output (LBO) is an open drain, so a pull-up resistor, R3, is required for proper
use. Adding a resistor divider at the Low Battery Input (LBI) pin gives the user the ability to
set at which value of V
Equation 1
SANYO POSCAP
Manufacturer
PANASONIC
Manufacturer
Coiltronics
Panasonic
Coilcraft
Distributor's capacitor main list (continued)
Distributor's inductor main list
Table
3).
BATT
TPA/B/C
EEFCD
Series
the (LBO goes high. The relationship is showed below:
V
LPO1704
LPO6610
ELL6SH
ELL6RH
Series
BATT TH
SD10
SD12
–
Cap value (µF)
22 to 230
22 to 47
=
1.23V
Inductor value (µH)
•
⎛
⎝
2.2 to 6.2
2.2 to 10
2.2 to 10
3.3 to 10
10 to 22
5.1 to10
1
+
Rated voltage (V)
R1
------- -
R2
⎞
⎠
6.3
6.3
Application information
Saturation current (A)
0.85 to 1.4
1.1 to 1.55
0.9 to 1.6
0.9 to 1.5
0.9 to 1.6
0.9 to 1.5
ESR (mΩ)
REF
50 to 700
40 to 80
voltage
5/11