Datasheet

GND
VOUT
VIN
VOUT
GND
VIN
GNDS
VINS
SW
GNDS
VOUTS
EN
Edge Connector www.ti.com
10 Edge Connector
Figure 3 shows net names of the edge connector pins. The top side of the edge connector is connected to
the power traces of the LMR70503 demo board. The bottom side are signal pins. The VINS, VOUTS and
GNDS pins are sensing pins for V
IN
, V
OUT
and ground respectively. The sensing pins are connected to the
power nets via net ties close to the IC. They are designed for more accurate efficiency measurement
when edge connector is used. Additional voltage drops on the edge connector are bypassed if efficiency is
measured by:
I
OUT
× (VOUTS – GNDS) / (I
IN
× (VINS – GNDS)) (3)
Figure 3. Edge Connector
11 LMR70503 Bill of Materials
V
IN
= 2.8 V to 5.5 V, V
OUT
has options of -0.9 V, -1.5 V, -2.5 V, -3.3 V, and -5.0 V. Optimized for minimum
solution size.
Table 1. Bill of Materials
Designator Value Case Size Manufacturer Manufacturer P/N
U1 Inverting Buck-Boost 8-bump DSBGA Texas Instruments LMR70503
C
IN1
10 µF 10 V X5R 0603 TDK C1608X5R1A106M
C
O1
, C
O2
22 µF 6.3 V X5R 0603 TDK C1608X5R0J226M
C
ff
10PF 50V 5% NP0 0402 Murata GRM1555C1H100JZ01D
D Schottky 30 V 500 mA SOD882 NXP Semi PMEG3005EL
L 6.8 µH, 0.76 A 362 mΩ 2.0*2.0*1.2mm TDK VLS2012ET-6R8M
R
t
100 kΩ, 1%, 0.063W 0402 Vishay Dale CRCW0402100KFKED
R1, R3 422 kΩ, 1%, 0.063W 0402 Vishay Dale CRCW0402422KFKED
R2 820 kΩ, 5%, 0.063W 0402 Vishay Dale CRCW0402820KFKED
R4 180 kΩ 1/16W 1% 0402 Vishay Dale CRCW0402180KFKED
R5 93.1 kΩ, 1%, 0.063W 0402 Vishay Dale CRCW040293K1FKED
R6, R7 20 kΩ, 5%, 0.063W 0402 Vishay Dale CRCW040220K0JNED
4
AN-2264 LMR70503 Demo Board SNVU155A–June 2012–Revised April 2013
Submit Documentation Feedback
Copyright © 2012–2013, Texas Instruments Incorporated